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SpaceX Vehicles and Missions => SpaceX Missions Section => Topic started by: gongora on 10/09/2017 04:25 PM

Title: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/09/2017 04:25 PM
DISCUSSION THREAD for Flight 4 of the Iridium NEXT missions.

Successfully launched December 22, 2017 at 5:27 p.m. PST on a reused Falcon 9 (1036.2) from SLC-4E at Vandenberg.  First stage was expended.

   Flight 4 will launch into plane 2.  One of the satellites will then drift to plane 1.

   NSF Threads for Iridium NEXT Flight 4: Discussion (https://forum.nasaspaceflight.com/index.php?topic=43940.0) / Updates (http://forum.nasaspaceflight.com/index.php?topic=44273.0) / L2 Coverage November-December (https://forum.nasaspaceflight.com/index.php?topic=44111.0) / ASDS (https://forum.nasaspaceflight.com/index.php?board=66.0) / Party (https://forum.nasaspaceflight.com/index.php?topic=40089.msg1520968#msg1520968)
   NSF Articles for Iridium NEXT Flight 4: 
https://www.nasaspaceflight.com/2017/10/iridium-4-flight-proven-falcon-9-rtls-vandenberg-delayed/
https://www.nasaspaceflight.com/2017/11/iridium-next-4-december-launch-vandenberg/
https://www.nasaspaceflight.com/2017/12/spacex-2017-campaign-iridium-4-launch/



See the Flight 1 Discussion Thread (https://forum.nasaspaceflight.com/index.php?topic=35112.0) for more information and links to other Iridium Next threads and articles.

General information for Iridium flights 1-5 & 7-8
   Payload Mass: 8600kg for 10 satellites + 1000kg for dispenser = 9600kg
   Launch orbit: 625km, 86.66 degrees
   Operational orbit: 778km, 86.4 degrees

81 Satellites will be built for Iridium NEXT, with 66 being needed for a fully operational constellation.  All of the satellites will carry ADS-B aviation tracking hosted payloads (https://forum.nasaspaceflight.com/index.php?topic=35112.msg1632414#msg1632414) for Aireon, and 60 of the satellites will carry AIS maritime tracking hosted payloads (https://forum.nasaspaceflight.com/index.php?topic=35112.msg1631005#msg1631005) for exactEarth.



Other SpaceX resources on NASASpaceflight:
   SpaceX News Articles (Recent) (https://www.nasaspaceflight.com/tag/spacex/)  /   SpaceX News Articles from 2006 (Including numerous exclusive Elon interviews) (https://forum.nasaspaceflight.com/index.php?topic=21862.0)
   SpaceX Dragon Articles (https://www.nasaspaceflight.com/tag/dragon/)  /  SpaceX Missions Section (with Launch Manifest and info on past and future missions) (https://forum.nasaspaceflight.com/index.php?board=55.0)
   L2 SpaceX Section (https://forum.nasaspaceflight.com/index.php?board=60.0)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/09/2017 05:12 PM
Quote
Tweet from Thales Alenia Space: (https://twitter.com/Thales_Alenia_S/status/917423111506677760)
#KeyFigure : 30 #IridiumNEXT #satellites now fully operational in #orbit. 17 ready to be shipped. 17 under integration. @IridiumComm
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ChrisGebhardt on 10/09/2017 10:44 PM
For planning purposes, take note that Iridium said multiple times today that this will be NET early December, not NET late-November.

There are "a couple things being finalized" along with a desire on Iridium's part to deconflict with the Thanksgiving holiday.

That's all I can say right now.

Matt Desch says a target date will be released by Iridium within the next two weeks.

(Edit: fixed grammar)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/10/2017 03:36 AM
For planning purposes, take note that Iridium said multiple times today that this will be NET early December, not NET late-November.

There are "a couple things being finalized" along with a desire on Iridium's part to deconflict with the Thanksgiving holiday.

That's all I can say right now.

Matt Desch says a target date will be released by Iridium within the next two weeks.

(Edit: fixed grammar)

Matt Desch tweeted this earlier today, maybe his evil twin got his Twitter password  :)
Quote
Nominally late November, but working schedule with SpaceX now.  Will inform world soon.

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Steven Pietrobon on 10/12/2017 07:05 AM
Matt Desch tweeted this earlier today, maybe his evil twin got his Twitter password  :)
Quote
Nominally late November, but working schedule with SpaceX now.  Will inform world soon.

Do you have a link for that tweet? I couldn't find it.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cartman on 10/12/2017 07:24 AM
https://twitter.com/IridiumBoss/status/917472121156132864
(its in tweets and replies)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Jakusb on 10/13/2017 07:49 AM
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 10/17/2017 11:53 PM
Quote
Matt Desch‏
@IridiumBoss

Unfortunately, I’m pretty sure we’re not going to be the first RTLS for our launch 4.  Wish it were true, but alas...

Now this has got me confused. What exactly would prevent this flight from being the first RTLS? Is it lack of performance? Regulations?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: yokem55 on 10/18/2017 12:03 AM
Quote
Matt Desch‏
@IridiumBoss

Unfortunately, I’m pretty sure we’re not going to be the first RTLS for our launch 4.  Wish it were true, but alas...

Now this has got me confused. What exactly would prevent this flight from being the first RTLS? Is it lack of performance? Regulations?
Performance. Getting 10 mt to polar orbit at 600 km is a bit too much for the current falcon to RTLS. Keep in mind, it needs  a bit more boostback since it won't have the rotation of the Earth bringing the launch site closer as well.

I'm guessing that the news about landing at VAFB has more to do with having the necessary permits to do so once block 5 is flying.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: 192 on 10/18/2017 12:05 AM
https://twitter.com/IridiumBoss/status/920015420777816065

There's also this ~24 hours earlier, could just be that he asked SpaceX and they said no RTLS, but he does say not the first RTLS rather than simply not RTLS. Is there any possibility SpaceX are planning a November Vandy launch now that Iridium 4 is December. I'd have thought we'd know about it by now if they were, but given we only just found out about Zuma and they still seem to be finalising Iridium 4 details according to Desch, maybe there's been a last minute schedule rearrangement.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/18/2017 12:13 AM
https://twitter.com/IridiumBoss/status/920015420777816065

There's also this ~24 hours earlier, could just be that he asked SpaceX and they said no RTLS, but he does say not the first RTLS rather than simply not RTLS. Is there any possibility SpaceX are planning a November Vandy launch now that Iridium 4 is December. I'd have thought we'd know about it by now if they were, but given we only just found out about Zuma and they still seem to be finalising Iridium 4 details according to Desch, maybe there's been a last minute schedule rearrangement.

No
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Chris Bergin on 10/19/2017 12:03 PM
Need to set up the update thread, will get on that.

Latest round up of upcoming manifest events and some additional details via L2 - by Chris Gebhardt:
https://www.nasaspaceflight.com/2017/10/spacex-zuma-iridium-4-aims-vandenberg-landing/

And with that there's been a change on the Iridium situation.

New article!

IR-4 now flight proven booster, the first from the West Coast! But back to Block 3, so can't RTLS as was the plan. Thanks to Iridium for being helpful in updating the status:

https://www.nasaspaceflight.com/2017/10/iridium-4-flight-proven-falcon-9-rtls-vandenberg-delayed/

- by Chris Gebhardt again :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Chris Bergin on 10/19/2017 12:15 PM
And the presser is out:

Iridium Announces Date for Fourth Iridium® NEXT Launch

Agreement Signed with SpaceX to Use Flight-Proven First Stage of Falcon 9 Rocket

MCLEAN, Va. – October 19, 2017 - Iridium Communications Inc. (NASDAQ: IRDM) announced today that the fourth Iridium NEXT launch has been targeted by SpaceX for December 22, 2017 at 5:26 p.m. PT [1:26 a.m. UTC on Dec. 23], from Vandenberg Air Force Base. This launch signifies the mid-way point of the Iridium NEXT launch program and will deliver another 10 satellites to orbit, bringing the total number deployed to 40. Targeted for just over two months after the third Iridium NEXT launch, this December date enables Iridium to maintain its planned cadence of completing all launches by mid-2018, even with SpaceX’s busy launch manifest.

To date, 30 Iridium NEXT satellites have been deployed, many of which are already providing service to customers. The new satellites are also now undergoing on-orbit testing for Iridium CertusSM, a major milestone on the path to introducing the company’s next generation broadband service.  Iridium Certus will feature small form factor, cost-effective terminals and antennas, and ultimately offer the fastest L-band broadband solution available, supported by the world's only truly global network.

In addition to the fourth launch date, Iridium also announced it has reached agreement with SpaceX to utilize flight-proven first stages for the next two Iridium launches.  Iridium conducted extensive due diligence work and is fully confident in the SpaceX booster refurbishment program.

“I believe that reusability is the future for satellite launches, and I think SpaceX has intelligently built their Falcon 9 program around this strategy,” said Iridium CEO Matt Desch. “With three successful flight-proven Falcon 9 launches already this year, we’re excited to show leadership towards the sustainable access to space, while also making sure we maintain our cadence to complete the five remaining Iridium NEXT launches by the middle of next year.”

Iridium confirmed with its insurers that there is no increase in premium for the launch program as a result of the use of flight-proven Falcon 9 rockets, further supporting Iridium’s conclusion that the risk profile is unchanged.

Iridium NEXT is the company’s $3 billion, next-generation, mobile, global satellite network scheduled for completion in 2018. Iridium NEXT will replace the company’s existing global constellation in one of the largest technology upgrades ever completed in space.  It represents the evolution of critical communications infrastructure that governments and organizations worldwide rely upon to drive business, enable connectivity, empower disaster relief efforts and more. Iridium NEXT will enable and introduce new services like the company’s next-generation communications platform, Iridium Certus, and the AireonSM space-based ADS-B aircraft surveillance and flight tracking network.

For more information about Iridium NEXT, please visit www.IridiumNEXT.com.

 

About Iridium Communications Inc.

Iridium is the only mobile voice and data satellite communications network that spans the entire globe. Iridium enables connections between people, organizations and assets to and from anywhere, in real time. Together with its ecosystem of partner companies, Iridium delivers an innovative and rich portfolio of reliable solutions for markets that require truly global communications. The company has a major development program underway for its next-generation network — Iridium NEXT. Iridium Communications Inc. is headquartered in McLean, Va., U.S.A., and its common stock trades on the NASDAQ Global Select Market under the ticker symbol IRDM. For more information about Iridium products, services and partner solutions, visit www.iridium.com.

###
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: swervin on 10/19/2017 01:34 PM
No increase in insurance premiums, and seemingly no increase in launch cadence (not an earlier launch date as a result of this contract modification), so what was the incentive to switch to flight-proven first stage? I'm all for it, but just curious on the business case to do so? Any word on discounted launch price or discounted follow-on launches?

This makes available to another customer a new core that would already be in testing, any words on who might be able to utilize this core?

Cheers!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 10/19/2017 01:40 PM
Maybe Project Zuma has requested a fresh core. Given the tight schedule, SpaceX had to reallocate the Iridium-N4 core but were able to talk Iridium into accepting a reused core.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 10/19/2017 01:52 PM
No increase in insurance premiums, and seemingly no increase in launch cadence (not an earlier launch date as a result of this contract modification), so what was the incentive to switch to flight-proven first stage?

Martin Halliwell of SES has been clear that their most recent use of a flight-proven booster was due to launch schedule, not price (see here (https://forum.nasaspaceflight.com/index.php?topic=42685.msg1737969#msg1737969)). As Matt Desch says in today's press release:

Quote
[...] while also making sure we maintain our cadence to complete the five remaining Iridium NEXT launches by the middle of next year.

So must have been a risk of schedule slips if they hadn't taken a flight-proven booster.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: swervin on 10/19/2017 02:10 PM
Maybe Project Zuma has requested a fresh core. Given the tight schedule, SpaceX had to reallocate the Iridium-N4 core but were able to talk Iridium into accepting a reused core.

The 'needs' of the Zuma customer do not make a business case for Iridium, in my opinion. Putting myself in Iridium's shoes: why do this?

Again, I'm all for it, just curious on the business case / motivation to do so.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 10/19/2017 02:12 PM
Putting myself in Iridium's shoes: why do this?

Again, I'm all for it, just curious on the business case / motivation to do so.
Iridium is doing this so they can fly sooner than if they waited for new cores.  That saves them money, rather than having birds on the ground longer waiting to go on orbit.  That is the business case and motivation.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: swervin on 10/19/2017 02:16 PM
So must have been a risk of schedule slips if they hadn't taken a flight-proven booster.

I'm not sure such an assertion can be made. This launch slipped from Oct to Nov, and it would seem the booster/parts and pieces would be well into their testing for a Nov launch date at this point. Now, with the flight-proven booster, the launch is NET 22 Dec, a significant slip from 'late-Nov'. How much more would one expect a new built booster to cause a launch slip further than the NET 22 Dec date? No way to know, just a bunch of spit-balling, so perhaps you're correct!

There was obviously a reason to make this decision and it is likely a combination of factors, just trying to figure it out. :-)

Cheers!

Edit: Fix quotes.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 10/19/2017 02:22 PM
Quote
So must have been a risk of schedule slips if they hadn't taken a flight-proven booster.

I'm not sure such an assertion can be made. This launch slipped from Oct to Nov, and it would seem the booster/parts and pieces would be well into their testing for a Nov launch date at this point. Now, with the flight-proven booster, the launch is NET 22 Dec, a significant slip from 'late-Nov'. How much more would one expect a new built booster to cause a launch slip further than the NET 22 Dec date? No way to know, just a bunch of spit-balling, so perhaps you're correct!

There was obviously a reason to make this decision and it is likely a combination of factors, just trying to figure it out. :-)

Cheers!

SpaceX's manufacture rate for boosters is a known limitation on flight rate. Don't forget that Iridium needs 5 more flights, so insisting on a new booster for every flight certainly risks schedule slips down the road.

And SpaceX likely gave them a discount. Pretty sure that's what "has reached agreement" means. Desch has said previously that they wanted a bigger discount that SpaceX was willing to give to fly a used booster. Sounds like they found a middle ground amenable to both parties.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: swervin on 10/19/2017 02:33 PM
Putting myself in Iridium's shoes: why do this?

Again, I'm all for it, just curious on the business case / motivation to do so.
Iridium is doing this so they can fly sooner than if they waited for new cores.  That saves them money, rather than having birds on the ground longer waiting to go on orbit.  That is the business case and motivation.

Valid point. If Iridium has a couple dozen satellites fueled and waiting for launch I think this rings true. I can't find it, but believe Iridium said they have X-number of satellites either ready or in construction?

Thx!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 10/19/2017 02:57 PM
Maybe Project Zuma has requested a fresh core. Given the tight schedule, SpaceX had to reallocate the Iridium-N4 core but were able to talk Iridium into accepting a reused core.

The 'needs' of the Zuma customer do not make a business case for Iridium, in my opinion. Putting myself in Iridium's shoes: why do this?

It depends on how... insistent USG were over the timing of Project Zuma's launch. The term 'requestion' may have come into the discussions between Grumman and SpaceX. Basically Iridium may have found themselves choosing a launch on a reconditioned rocket or a schedule delay because of some USG launch priority clause in the launch contract.

I have no special insight as to whether this scenario is possible or likely but I would point out that governments can be somewhat unreasonable with their private-sector suppliers when they want something and want it now.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 10/19/2017 03:30 PM
The other thing to keep in mind is that SpaceX is trying to navigate a (likely unique) transition from being a fully expendable launch provider to a fully reliable launch provider.  They've talked about increasing production capacity for some time beyond what they have now, but it seems clear that they've been slow-rolling that for a while.  And it makes sense: why spend money to increase production capacity only to have to scale it back once their reuse plans reach fruition?  The flip side of that is it constrains their ability to catch up on their backlog and they have lots of customers waiting patiently for their ride to orbit.  The Amos incident really hurt in that regard as it set them back right when they were starting to gain some momentum.

It's hard to say what SpaceX is offering right now, but I think it wouldn't be surprising if they are offering some minor sweeteners (discounts) for those who were on the fence to get them on the reuse train sooner than later, and prevent further slippage in their future launch timelines.  This allows them to catch up on that backlog without having to build out capacity on their production line that they will soon not require.  It is a delicate balancing act to be sure.

The accelerated use of previously flown boosters will also help accelerate the adoption of reused boosters by industry as a normal thing and not exceptional.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: meberbs on 10/19/2017 03:39 PM
The accelerated use of previously flown boosters will also help accelerate the adoption of reused boosters by industry as a normal thing and not exceptional.
This is somewhat circular logic - not wrong, just circular in a way that implies self fueling exponential growth in fraction of reuse missions. Although it has to s-curve and level out somewhere short of 100% since at least some boosters have to be new.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 10/19/2017 04:01 PM
The accelerated use of previously flown boosters will also help accelerate the adoption of reused boosters by industry as a normal thing and not exceptional.
This is somewhat circular logic - not wrong, just circular in a way that implies self fueling exponential growth in fraction of reuse missions. Although it has to s-curve and level out somewhere short of 100% since at least some boosters have to be new.
What I was driving at with my statement is first, the combination of a large backlog and insufficient production capacity to meet that backlog in a timely manner is pushing both SpaceX and their customers to accelerate adoption of reused boosters.  Although in reality SpaceX is also driving this, by choosing not to expand their production capacity and offer reused boosters in lieu of doing so.  (My interpretation, but I'm not offering any unique insights here).

Second, there is a very short flight curve due to how the rocket business normally operates, where very few operational flights are required before a rocket is considered to be viable as compared to most other industries.  Historically, three successful flights of a rocket is usually sufficient for it to be considered operational.  A reused booster is a new wrinkle but I think a lot of those benchmarks still apply.  So you can get an avalanche affect here where pretty quickly a lot of customers on the commercial side will become comfortable with reuse very rapidly, as demonstrated just now by Iridium.  We're only eight months since the first orbital reuse!  Quite remarkable really.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: DecoLV on 10/19/2017 04:48 PM
Still confused about RTLS thing. Wasn't RTLS to the new pad planned up until this booster change? I thought it was ready to go. New mfg v. flight-proven should make no difference.

Would this S1 now go to a drone ship?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 10/19/2017 04:55 PM
Still confused about RTLS thing. Wasn't RTLS to the new pad planned up until this booster change? I thought it was ready to go. New mfg v. flight-proven should make no difference.
Block 4 can RTLS given this payload and orbit, Block 3 cannot.  The reused booster is Block 3, so switching to it has taken RTLS off the table.
Quote
Would this S1 now go to a drone ship?
Yes.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/19/2017 09:56 PM
Quote
Tweet from Matt Desch (https://twitter.com/IridiumBoss/status/921070386640556032):
Comfort that risk <= than new and more schedule certainty to complete 5 more launches over next 8 months.  Cost is better, but not driver.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 10/23/2017 03:55 PM
FCC permit applications filed today, mission 1340 with droneship landing, NET Dec 22.  Iridium flights 2-4 are missions 1338-1340.  It will be interesting to see what number is used for flight 6.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Raul on 10/23/2017 07:08 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ZachS09 on 10/23/2017 07:41 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

Are you sure there's no boostback burn during Iridium-NEXT F4?

I thought all previous Iridium-NEXT missions used a partial boostback burn.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 10/23/2017 07:49 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

Are you sure there's no boostback burn during Iridium-NEXT F4?

I thought all previous Iridium-NEXT missions used a partial boostback burn.

They did, I wonder why there's no boostback.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: MarekCyzio on 10/23/2017 07:55 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

My theory  - this is Block 4 - will be reused more than once - reduce unnecessary wear on the rocket.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Barrie on 10/23/2017 08:08 PM
They decided the fuel they would use for partial boostback is better used for a beefed-up re-entry burn? ie more likely to get a re-usable booster back that way?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ChrisGebhardt on 10/23/2017 08:19 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

My theory  - this is Block 4 - will be reused more than once - reduce unnecessary wear on the rocket.

Iridium-4 is reusing a flight-proven Block 3 at present.  It will likely be the same booster that launched Iridium-2 in June.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: SweetWater on 10/23/2017 09:08 PM
They decided the fuel they would use for partial boostback is better used for a beefed-up re-entry burn? ie more likely to get a re-usable booster back that way?

Hard to say, but it certainly seems like a possibility. I think we're all starting to feel that successful F9 stage 1 landings are, if not routine, certainly becoming expected (provided the landing is attempted at all); however, we should bear in mind that SpaceX has only recovered 18 (by my count) stages at this point. They're likely still learning how the stages fare after different types of missions (LEO vs. GTO) and and recovery locations (downrange vs. on land).

I would expect to see some variety in recovery strategies with the continued use of Block 4 and the introduction of Block 5 vehicles, if only to see how those vehicles (and the materials used on them) compare to SpaceX's expectations for a given mission and type of recovery.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ATPTourFan on 10/24/2017 01:23 PM
My first thought was that SpaceX is giving Iridium as much margin as possible to get their payload to the proper orbit. Iridium and SpaceX worked out the arrangement to utilize the flight-proven core to help schedule this launch, but SpaceX really doesn't need to be gentle to this core as much as they MUST get Iridium-4 payload where it needs to go - maximum margins to make customer happy.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gth871r on 10/24/2017 01:25 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

Iridium 2 was the flew with the Titanium grid fins.  (I think it's the only booster, to date that has done so.)  They may be interested in pushing those a little harder to see what happens.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ZachS09 on 10/24/2017 02:10 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

Iridium 2 was the flew with the Titanium grid fins.  (I think it's the only booster, to date that has done so.)  They may be interested in pushing those a little harder to see what happens.

That's if SpaceX decides to keep the titanium fins on B1036. For the past five missions after Iridium-NEXT F2 (excluding Intelsat 35e), they've been using the aluminum fins, so there's a chance that the latter will be used during Iridium-NEXT F4.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cambrianera on 10/24/2017 07:09 PM
It's interesting that there will be apparently no boostback burn during the booster landing of this mission.
Planned ASDS recovery position is as far as 513km downrange, similarly like in Cassiope water landing attempt.

Iridium-1 block 3 B1029.1 had landing position 372km downrange. Iridium-2 326km and Iridium-3 244km.

In the Map (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&ll=32.1692739987226%2C-120.73069496795557&z=7)

Iridium 2 was the flew with the Titanium grid fins.  (I think it's the only booster, to date that has done so.)  They may be interested in pushing those a little harder to see what happens.

May be that the enhanced attitude control and capabilities of Ti grid fins enables Spacex to try a lifting reentry, keeping the stage "afloat" in the upper layers of the atmosphere.
This would reduce the heat rate and the peak heating, avoiding the reentry burn and saving lot of propellant.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: oiorionsbelt on 10/24/2017 10:52 PM
however, we should bear in mind that SpaceX has only recovered 18 (by my count) stages at this point.
That this comment was made at all is immensely satisfying. 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 10/25/2017 08:06 AM
however, we should bear in mind that SpaceX has only recovered 18 (by my count) stages at this point.
That this comment was made at all is immensely satisfying. 
Indeed. But what is much more important is that three of those recovered booster have already been re-flown with several more re-flights coming up in the next few months.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 10/27/2017 03:36 PM
An interesting possibility FYI cross-posting from the GCOM-C launch thread (https://forum.nasaspaceflight.com/index.php?topic=44066.0):

http://global.jaxa.jp/press/2017/10/20171027_h2af37.html

Launch of Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C)  and Super Low Altitude Test Satellite TSUBAME" (SLATS) aboard H-IIA Vehicle No. 37

October 27, 2017 (JST)

Mitsubishi Heavy Industries, Ltd.
National Research and Development Agency
Japan Aerospace Exploration Agency (JAXA)

Mitsubishi Heavy Industries, Ltd. (MHI) and the Japan Aerospace Exploration Agency (JAXA) are pleased to announce the launch schedule for Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C) and Super Low Altitude Test Satellite "TSUBAME" (SLATS) by H-IIA launch vehicle No. 37.

Scheduled date of Launch : December 23 (Sat.), 2017
Launch time                    : 10:26:22 a.m. through 10:48:22 a.m. (JST)
Reserved Launch period   : December 24 (Sun.), 2017 through January 31 (Wed.), 2018
Launch site                     : Yoshinobu Launch Complex at the tanegashima Space Center 

<snip>

And:
Note that as of right now, the start of the launch window for this falls on the exact same minute (!!!) as for the launch of Falcon 9/Iridium NEXT Flight 4 on the opposite side of the Pacific. IF (a very big one) this ultimately happens the two will be <=37 seconds apart, which will be an all time record (http://forum.nasaspaceflight.com/index.php?topic=43064.msg1692147#msg1692147).  :o

I very much doubt both will manage to hold on schedule to that point with 57 days left but.....one never knows for sure when will we need split screens.  ;) ;)

Technical info on GCOM-C can be found here (https://directory.eoportal.org/web/eoportal/satellite-missions/g/gcom), and for SLATS here (https://directory.eoportal.org/web/eoportal/satellite-missions/s/slats).
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: WizZifnab on 10/28/2017 02:42 PM
So seems that switching to ASDS landing instead of RTLS on this launch was due to the decision to launch using a previously flown booster.

However, is it possible that it had more to do with taking advantage of the Titanium grid fins for testing an alternate downrange reentry profile, than the fact that it will now be a Block III booster?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IntoTheVoid on 10/28/2017 03:49 PM
So seems that switching to ASDS landing instead of RTLS on this launch was due to the decision to launch using a previously flown booster.

However, is it possible that it had more to do with taking advantage of the Titanium grid fins for testing an alternate downrange reentry profile, than the fact that it will now be a Block III booster?

During the post-landing processing they remove the grid fins (based on images we've seen in the garage) and the titanium grid fins are mechanically compatible with the mounts for the Al ones, so there's not really any reason to think that this booster will again have the Ti fins, or that if they wanted to test them on a particular re-entry profile that they couldn't have done so already, either on Iridium 3 or one of the east coast launches.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: the_other_Doug on 10/29/2017 10:56 PM
So seems that switching to ASDS landing instead of RTLS on this launch was due to the decision to launch using a previously flown booster.

However, is it possible that it had more to do with taking advantage of the Titanium grid fins for testing an alternate downrange reentry profile, than the fact that it will now be a Block III booster?

During the post-landing processing they remove the grid fins (based on images we've seen in the garage) and the titanium grid fins are mechanically compatible with the mounts for the Al ones, so there's not really any reason to think that this booster will again have the Ti fins, or that if they wanted to test them on a particular re-entry profile that they couldn't have done so already, either on Iridium 3 or one of the east coast launches.

Do the Al and Ti grid fins provide the exact same amounts of control per fin motion?

I could imagine that the Al grids, being closer together and composed of a smaller grid pattern, might provide slightly different pressures to control the rocket than the Ti fins do; their different weights may also impact the control motions.  Neither type of grid fin being "better" or "worse" from a control perspective; just different.

You'd have to program the FCS software running the entry and landing targeting to the type of fin being used, though, no?  Or would you load both sets of response thresholds into the FCS software, and spend a bunch of your processor time selecting between them from menus?

Old-fashioned, "how it's always been done" process would be to tailor the FCS for the specific vehicle's hardware config, I imagine.  I wonder how SpaceX is doing it?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: old_sellsword on 10/29/2017 11:25 PM
...I could imagine that the Al grids, being closer together and composed of a smaller grid pattern, might provide slightly different pressures to control the rocket than the Ti fins do...

The Titanium fins have the exact same grid pattern and spacing, they just* added an extra row on the end and scalloped the underside.

*Obviously it was more complicated than that
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AC in NC on 10/30/2017 01:50 AM
You'd have to program the FCS software running the entry and landing targeting to the type of fin being used, though, no?  Or would you load both sets of response thresholds into the FCS software, and spend a bunch of your processor time selecting between them from menus?

Old-fashioned, "how it's always been done" process would be to tailor the FCS for the specific vehicle's hardware config, I imagine.  I wonder how SpaceX is doing it?

Putting together a reading of how IIP is handled as well as the unknowns posed by atmospheric conditions and degradation we've seen in AL fins, I'd be surprised if the FCS wasn't written to be able to adapt (as best it can) to whatever control authority is available with the result being no "tailoring" necessary.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 11/06/2017 10:56 AM
Just noticed something that doesn't appear to have been picked up in the Iridium NEXT flight 3 threads.

A few days before the 3rd launch, the FAA issued a minor revision to the launch license (attached):

Quote
Revision 2 - Issued October 6, 2017
   1.   Paragraph (3)(c) changed from "On a flight azimuth of 179.2 degrees" to "On a flight azimuth between 175 and 180 degress
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 11/06/2017 01:51 PM
Just noticed something that doesn't appear to have been picked up in the Iridium NEXT flight 3 threads.

A few days before the 3rd launch, the FAA issued a minor revision to the launch license (attached):

Quote
Revision 2 - Issued October 6, 2017
   1.   Paragraph (3)(c) changed from "On a flight azimuth of 179.2 degrees" to "On a flight azimuth between 175 and 180 degress
Caused by switch from RTLS to ASDS landing, perhaps?  Gives additional flexibility to target the ASDS even if there are weather issues forcing a slight relocation of the ASDS? Just a wild guess.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 11/07/2017 08:01 PM
Quote
First 2 sats for Launch #4 on their way from AZ factory to VAFB!  Only a little more than 6 weeks away - 12/22! (Tracked via Iridium IoT)

https://twitter.com/iridiumboss/status/928002624670101504
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 11/08/2017 02:31 AM
Quote
(Tracked via Iridium IoT)

https://twitter.com/iridiumboss/status/928002624670101504

Yaay for eating your own dogfood!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 11/10/2017 01:23 PM
Quote
Launch 4 activities on track for a Dec 22nd launch.  Second two of 10 Iridium NEXT sats just left for VAFB - all there by Thanksgiving weekend.  First stage and dispenser onsite.  2018 schedule firming up too... Halfway home!

https://twitter.com/iridiumboss/status/928987644863959041
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 11/21/2017 09:34 PM
This guy makes some sweet models.

Tweet from Oli Braun (https://twitter.com/oli_braun/status/930101280068001792):
Quote
Very honored to have had the opportunity to make these for @IridiumBoss I hope these 4 will be happy at their new home :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: MATTBLAK on 11/21/2017 09:53 PM
Those models are... amazing :o

Oliver and friend's website:  http://www.buzz-medialabs.de/
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Zardar on 11/21/2017 11:18 PM
Those models are... amazing :o

Oliver and friend's website:  http://www.buzz-medialabs.de/

Well, for the 4th model, he should have just made the top bits, and told them to re-use one of the other first-stages.





Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: stcks on 11/21/2017 11:47 PM
There is something sneaky hidden behind the third one ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 11/22/2017 04:24 AM
There is something sneaky hidden behind the third one ;)
Well spotted, sir!! I’m seeing the same.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 11/22/2017 05:38 AM
There is something sneaky hidden behind the third one ;)
Well spotted, sir!! I’m seeing the same.
Sneaky?
It looks like a fifth Falcon 9.
The clear support is the same as for the three up front.
It may be rotated so only the wiring channel sticks out from behind the third f9.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mgeagon on 11/22/2017 06:08 AM
There is something sneaky hidden behind the third one ;)
It appears to be a commercial crew block 5 Falcon 9. It has a Dragon 2 capsule and service module, a black interstage and landing legs, and titanium grid fins. Very nice!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 11/22/2017 06:37 AM
There is something sneaky hidden behind the third one ;)
It appears to be a commercial crew block 5 Falcon 9. It has a Dragon 2 capsule and service module, a black interstage and landing legs, and titanium grid fins. Very nice!
Well spotted.
I think it is a safe bet that SpaceX actually commissioned Oli to do those customer-relations models. There is simply too much stuff on those models to have been made without SpaceX input. Particularly the block 5 model given that the information about the black interstage and black landing legs for block 5 only became public information very recently.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: MATTBLAK on 11/22/2017 09:57 AM
I think SpaceX is really missing an opportunity for marketing - they should be selling spacecraft and rocket models that both kids and adult collectors (me) can get their teeth into. I'd love to see kids whooshing and flying around the house and their yards with Dragons, Falcons and BFRs, instead of X-Wings and TIE fighters all the time! ;)

They could also have launch pad and recovery barge models. There could be two price points: play toys for kids and higher fidelity models for people's display cabinets (such as mine):
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 11/22/2017 01:03 PM
We’re off-topic but I second that. Partner with LEGO and Estes for a line of buildable block toys and a line of flyable model rockets. Perhaps even design the thing in such a fashion that the landing legs open upon decent and it has a decent chance of landing upright. Estes rockets are already reusable. Could be part of the fun seeing if it does land. Probably would prompt more launches and use more Estes motors. Win win win.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 11/22/2017 05:40 PM
They've already made and sold two different versions of a flying estes-style model F9: one with dragon capsule on top, and one with fairing.  A number of us rocket modelers have used the F9 kits to bash together flying FH models.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: kdhilliard on 11/27/2017 05:55 PM
Do we know whether or not the same fairing concerns which have delayed Zuma also apply to this Iridium launch?

Edit: Apparently Matt Desch answered just this question yesterday, tweeting (https://twitter.com/IridiumBoss/status/934816884599480320):
Quote
Quote
Uwe Häntsch‏ @uwelinchen 1 Nov 25

@IridiumBoss Good afternoon, Mr. Desch. Is the date on December 22nd for the next Iridium flight still up to date? SpaceX has problems with payload fairing. Thanks for the information.
Matt Desch‏ @IridiumBoss 8:11 AM - 26 Nov 2017

Yes, Dec 22nd is still our date.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mn on 11/28/2017 02:05 PM
Fairing not an issue for this flight...

Iridium NEXT-4 on track for December launch from Vandenberg -
https://www.nasaspaceflight.com/2017/11/iridium-next-4-december-launch-vandenberg/

- By Chris Gebhardt

Does this mean it was  never an issue? or that there was enough time to fix/replace and encapsulate and still meet the schedule?

It's not clear to me from the tweet that it was not an issue, he sort of sidestepped the question about the fairing, just confirmed the date.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 11/28/2017 02:17 PM
The Iridium Press Release (http://investor.iridium.com/releasedetail.cfm?ReleaseID=1049952):
Quote
Iridium Nears Launch Campaign Midway Point as All 10 Satellites Arrive at Vandenberg Air Force Base
Iridium-4 to create historic moment, making Iridium the first company to re-use the same rocket booster

MCLEAN, Va., Nov. 28, 2017 (GLOBE NEWSWIRE) -- Iridium Communications Inc. (NASDAQ:IRDM) announced today that all 10 Iridium® NEXT satellites for its fourth launch are now in processing at SpaceX's west coast launch site at Vandenberg Air Force Base in California. This launch will mark the midway point of Iridium's launch campaign with SpaceX, and is the first of two Iridium NEXT launches utilizing "flight-proven" SpaceX Falcon 9 rockets. Iridium-4 is currently scheduled for December 22, 2017 at 5:32 pm PST, with a backup date of December 23rd.

Noteworthy for the fourth launch, the same Falcon 9 rocket first stage that carried 10 Iridium NEXT satellites for the company's second launch in June of 2017, will also carry this payload of 10 satellites. This will make Iridium the first company in history to reuse the same rocket. Upon arrival at the launch site, each Iridium NEXT satellite began a number of pre-launch processing steps, including mating to the dispenser, fueling and encapsulation within the fairing.  The satellites were shipped two at a time, in specially-designed motion and temperature-controlled containers designed to maintain optimal environmental conditions.

"We're approaching our halfway point on this journey, and with each launch, we gain more momentum," said Iridium CEO Matt Desch. "This launch will bring us to 40 Iridium NEXT satellites in space, which is more than half the number required for a full Iridium NEXT operational constellation.  It has been remarkable to witness the increased speed, capacity and throughput of our network as we continue to replace our original satellites with new Iridium NEXT satellites."

The operational Iridium constellation is comprised of 66 satellites divided into six polar orbiting planes with 11 satellites in each plane. Destined for Iridium orbital plane two, nine of the 10 Iridium NEXT satellites deployed during this launch will immediately go into service following rigorous testing and validation. The remaining satellite will undertake a nearly year-long journey to orbital plane one, where it will serve as a spare satellite.  To date, three Iridium NEXT launches carrying 10 satellites each have been completed. The fourth launch will bump the total number of new Iridium NEXT satellites in orbit to 40. Iridium has contracted with SpaceX to deliver 75 Iridium NEXT satellites to orbit, 66 operational and nine on-orbit spares, through a series of eight launches.

Iridium NEXT is the company's $3 billion next-generation mobile, global satellite network scheduled for completion in 2018. Iridium NEXT will replace the Company's existing global constellation in one of the largest technology upgrades ever completed in space.  It represents the evolution of critical communications infrastructure that governments and organizations worldwide rely upon to drive business, enable connectivity, empower disaster relief efforts and more. Iridium NEXT will enable and introduce new services like the Company's next-generation communications platform, Iridium CertusSM, and the AireonSM space-based ADS-B aircraft surveillance and flight tracking network. 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 12/02/2017 04:35 AM
Kevin Fetter posted about this FCC Public Notice, Report No. SAT-01286, on Seesat-l at http://www.satobs.org/seesat/Dec-2017/0004.html .

http://transition.fcc.gov/Daily_Releases/Daily_Business/2017/db1201/DOC-348023A1.pdf
Quote
Iridium Constellation LLC requests modification of its license for a non-geostationary, mobile-satellite service constellation. Iridium seeks an extension of the license term for its first-generation satellites until July 31, 2019, and authority to maintain up to 18 first-generation satellites as in-orbit spares during the transition to its second-generation satellite system.

(I didn't find a thread discussing the final dispositions of the first generation Iridium satellites.  If there's a better thread to post this to, please make a suggestion.)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 12/02/2017 11:22 PM
Will launch processing be suspended if there is a government shutdown when the current funding legislation expires at 12 am December 9?

Parallel questions have been asked on the CRS-13 discussion thread and the NROL-47 thread.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/03/2017 02:57 AM
Will launch processing be suspended if there is a government shutdown when the current funding legislation expires at 12 am December 9?

Parallel questions have been asked on the CRS-13 discussion thread and the NROL-47 thread.

Why would processing be suspended?  The only government interaction for this part of the flow is safety and base security.  Those shouldn't be affected.  Iridium is doing the payload processing and SpaceX the F9 processing in SpaceX's facilities,  SpaceX already has a launch license for this mission, so no regulatory interactions yet.  The only thing I'm not sure about is static fire and launching, where SpaceX will need range support and interaction with other federal agencies.  But, as their involvement should all be classified as ensuring public safety, even if they are initially affected I imagine they'd get waivers pretty quick.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 12/12/2017 05:04 PM
Static fire date/time?

(I assume it hasn't been announced yet, or it would already have been posted on NSF!)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: whitelancer64 on 12/12/2017 05:25 PM
Will launch processing be suspended if there is a government shutdown when the current funding legislation expires at 12 am December 9?

Parallel questions have been asked on the CRS-13 discussion thread and the NROL-47 thread.

When there's a government "shutdown" that doesn't mean all government-run things actually shut down... most of the government is still operating. Military operations (including launch sites) continue to function as though nothing happened. It's just the non-essential, highly-annoying-to-the-public things that get shut down, especially tourist attractions like memorials and national parks. During the 2013 shutdown, about 1/4 of federal employees were furloughed (but they were paid for that time off later). The IRS was particularly hurt by this, but most other agencies functioned fairly normally.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: rockets4life97 on 12/17/2017 10:52 PM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Chris Bergin on 12/17/2017 11:04 PM
Chris G is going there for NSF....but he's stuck in Atlanta Airport still as of last check.

We also have Philip, Jay and Helo who go to launches there, but today was a perfect mix of it being a Sunday and so many other things going on.

And after all, aren't we "hoping" the launch cadence will get to the point there will be Static Fires and launches every week, meaning the main focus will be on the launch? :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Michael Baylor on 12/17/2017 11:05 PM
Part of the problem is that there just aren't that many sources. At the Cape, all the NASA employees are alerted about the static fire. A few of them will let Chris^2 know. Not as many sources at Vandenberg.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Chris Bergin on 12/17/2017 11:12 PM
Yeah, Vandy is tough. We have a few ins, but.....it's a Sunday. People tell us things. We never badger them into giving us info. The second this place becomes a chore for people who can help us....well I'm not going that mass media route. Keeping this place a no pressure cool site means more people end up helping, so that's the long game, but the best game.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Michael Baylor on 12/17/2017 11:13 PM
Also, SLC 40 at Cape Canaveral is visible from publicly accessible areas.  SLC 4E at Vandenberg AFB is, as I understand it, essentially hidden from public view by topography.  VAFB is much more militarily active than the Cape, and thus its goings-on are less discussed by locals.

 - Ed Kyle
Correct

It is partially visible from far away on a mountain road, but the primary public viewing site is obstructed. Most people aren't going to  go out of their way and drive on some windy road just to get a partial view of the pad (although I totally would if I lived near there).

View of the pad:
https://www.youtube.com/watch?v=9gNmDTjaVB8
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/17/2017 11:24 PM
Chris G is going there for NSF....but he's stuck in Atlanta Airport still as of last check.

What a mess that is.  Good luck Chris.  If you need extraction there are plenty of NSF'ers around the metro area, just shine the bat shuttle F9 signal  :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: shuttlefan on 12/18/2017 12:10 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 12/18/2017 12:47 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Earlier today apparently.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: meekGee on 12/18/2017 06:55 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Earlier today apparently.

Thus proving that things happen even while NSF is not paying attention.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Pete on 12/18/2017 06:59 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Earlier today apparently.

Thus proving that things happen even while NSF is not paying attention.

The launch is happening on the "wrong" coast, thus as with all previous Vandenberg launches, it is virtually ignored in this forum.
I've seen the discussion get started less than 48 hours before the planned launch date.

By comparison, we have launch discussions for Florida that predate the launch by seasons, sometimes years.

I guess Vandy is just the unloved child in the family.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Galactic Penguin SST on 12/18/2017 07:14 AM
An interesting possibility FYI cross-posting from the GCOM-C launch thread (https://forum.nasaspaceflight.com/index.php?topic=44066.0):

http://global.jaxa.jp/press/2017/10/20171027_h2af37.html

Launch of Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C)  and Super Low Altitude Test Satellite TSUBAME" (SLATS) aboard H-IIA Vehicle No. 37

October 27, 2017 (JST)

Mitsubishi Heavy Industries, Ltd.
National Research and Development Agency
Japan Aerospace Exploration Agency (JAXA)

Mitsubishi Heavy Industries, Ltd. (MHI) and the Japan Aerospace Exploration Agency (JAXA) are pleased to announce the launch schedule for Global Changing Observation Mission - Climate "SHIKISAI" (GCOM-C) and Super Low Altitude Test Satellite "TSUBAME" (SLATS) by H-IIA launch vehicle No. 37.

Scheduled date of Launch : December 23 (Sat.), 2017
Launch time                    : 10:26:22 a.m. through 10:48:22 a.m. (JST)
Reserved Launch period   : December 24 (Sun.), 2017 through January 31 (Wed.), 2018
Launch site                     : Yoshinobu Launch Complex at the tanegashima Space Center 

<snip>

And:
Note that as of right now, the start of the launch window for this falls on the exact same minute (!!!) as for the launch of Falcon 9/Iridium NEXT Flight 4 on the opposite side of the Pacific. IF (a very big one) this ultimately happens the two will be <=37 seconds apart, which will be an all time record (http://forum.nasaspaceflight.com/index.php?topic=43064.msg1692147#msg1692147).  :o

I very much doubt both will manage to hold on schedule to that point with 57 days left but.....one never knows for sure when will we need split screens.  ;) ;)

Technical info on GCOM-C can be found here (https://directory.eoportal.org/web/eoportal/satellite-missions/g/gcom), and for SLATS here (https://directory.eoportal.org/web/eoportal/satellite-missions/s/slats).

Many weeks later and......this is still predicted to happen as of this writing. With the F9 settling on T-0 at 01:27:23 UTC the 2 launches will be 61 seconds apart if everything goes as planned (the H-IIA will launch first).  ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 12/18/2017 07:16 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Earlier today apparently.

Thus proving that things happen even while NSF is not paying attention.

The launch is happening on the "wrong" coast, thus as with all previous Vandenberg launches, it is virtually ignored in this forum.
I've seen the discussion get started less than 48 hours before the planned launch date.

By comparison, we have launch discussions for Florida that predate the launch by seasons, sometimes years.

I guess Vandy is just the unloved child in the family.

Unloved child?

No, not really. Just relatively far away from easy public viewing, contrary to CCAFS.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Helodriver on 12/18/2017 07:59 AM
Vandenberg gets plenty of love from a few people in particular. Even then I didn't get a heads up about a static fire today. I also had Star Wars tickets. :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/18/2017 09:00 AM
Tweet from Matt Desch (https://twitter.com/IridiumBoss/status/942568277447991297):
Quote
My schedule, provided by SpaceX shows it as 5:27:23 PST...

I assume he meant 17:27:23 PST ...?!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: docmordrid on 12/18/2017 10:35 AM
We need some more space reporters out at Vandenberg. The successful static fire attempt wasn't even publicly posted as occurring. Very different than static fires occurring at the Cape.

When did the static fire ocurr?
Earlier today apparently.

Thus proving that things happen even while NSF is not paying attention.

Confirmation

SpaceX ✔ @SpaceX
Static fire test of Falcon 9 complete targeting December 22 launch of Iridium-4 from Vandenberg AFB in California.
6:49 PM - Dec 17, 2017
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: e of pi on 12/18/2017 02:04 PM
Launch Four Iridium Emblem
I'm amused by the belt-and-suspenders approach to luck on this flight: the traditional clover leaf, plus a horseshoe, both hiding in Lady Liberty. :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: JoeAlvord on 12/18/2017 02:17 PM
Launch Four Iridium Emblem
I'm amused by the belt-and-suspenders approach to luck on this flight: the traditional clover leaf, plus a horseshoe, both hiding in Lady Liberty. :)

Not as much as you might think.   The horseshoe is upside down.  All the good luck will drain out.  On the other hand, it will be in zero-G.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/18/2017 02:42 PM
https://www.noozhawk.com/article/spot_fires_reported_on_vandenberg_air_force_base (https://www.noozhawk.com/article/spot_fires_reported_on_vandenberg_air_force_base)

Correction: The incident was after 1500 local.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: scdavis on 12/18/2017 06:49 PM
https://twitter.com/iridiumcomm/status/942830392092000256


This picture really puts the fairing into perspective. I knew it was large, but this gives a real feeling for just how large it really is! No wonder SpaceX  wants to recover it.

Edit: linking to the image attached by FutureSpaceTourist... hope I'm doing this right.

Mod edit:please attach images, not directly embedding them.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: sevenperforce on 12/18/2017 09:19 PM
https://twitter.com/iridiumcomm/status/942830392092000256


This picture really puts the fairing into perspective. I knew it was large, but this gives a real feeling for just how large it really is! No wonder SpaceX  wants to recover it.

Edit: linking to the image attached by FutureSpaceTourist... hope I'm doing this right.
Poring over that photo for any glimpse of recovery hardware...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureMartian97 on 12/19/2017 12:41 AM
A user on r/SpaceX is saying this core is flying expendable. Can anyone confirm this? And if its true, why? I know they are probably running out of room to store them but its still more data and more usable engines.

https://www.reddit.com/r/spacex/comments/7cgts7/iridium_next_constellation_mission_4_launch/drg64bk/
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/19/2017 12:56 AM
A user on r/SpaceX is saying this core is flying expendable. Can anyone confirm this? And if its true, why? I know they are probably running out of room to store them but its still more data and more usable engines.

https://www.reddit.com/r/spacex/comments/7cgts7/iridium_next_constellation_mission_4_launch/drg64bk/

He said he got the info from a friend at Vandy. I'm still thinking it's unlikely to be going expendable, but this comment, even if the guy isn't proven reliable, might challenge that.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: virnin on 12/19/2017 01:20 AM
A user on r/SpaceX is saying this core is flying expendable. Can anyone confirm this? And if its true, why? I know they are probably running out of room to store them but its still more data and more usable engines.

https://www.reddit.com/r/spacex/comments/7cgts7/iridium_next_constellation_mission_4_launch/drg64bk/

He said he got the info from a friend at Vandy. I'm still thinking it's unlikely to be going expendable, but this comment, even if the guy isn't proven reliable, might challenge that.

Potentially just a huge misinterpretation.

Poster:  Are they going to land the booster at Vandy?

Friend:  No, they aren't going to land it here.

Poster: Then it must be expendable!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Jdeshetler on 12/19/2017 01:32 AM
Inside source at Iridium said it does have a merit and yet it is up to SpaceX to confirm it.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Nomadd on 12/19/2017 01:51 AM
 It could just be a matter of the barge not being available for some reason.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: leetdan on 12/19/2017 01:59 AM
Potentially just a huge misinterpretation.

Poster:  Are they going to land the booster at Vandy?

Friend:  No, they aren't going to land it here.

Poster: Then it must be expendable!

The phrase "does not have the grid fins and landing legs" doesn't really lend itself to misinterpretation ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Wolfram66 on 12/19/2017 02:18 AM
Potentially just a huge misinterpretation.

Poster:  Are they going to land the booster at Vandy?

Friend:  No, they aren't going to land it here.

Poster: Then it must be expendable!

The phrase "does not have the grid fins and landing legs" doesn't really lend itself to misinterpretation ;)

This from Spaceflight101.com http://spaceflight101.com/spacex-falcon-9-completes-static-fire-test-for-year-closing-launch/ (http://spaceflight101.com/spacex-falcon-9-completes-static-fire-test-for-year-closing-launch/)

Appears to have both fins and legs. Alas, this is from the first flight of B1036, hence the freshly painted appearance & no sooty goodness
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/19/2017 02:20 AM
Potentially just a huge misinterpretation.

Poster:  Are they going to land the booster at Vandy?

Friend:  No, they aren't going to land it here.

Poster: Then it must be expendable!

The phrase "does not have the grid fins and landing legs" doesn't really lend itself to misinterpretation ;)

This from Spaceflight101.com http://spaceflight101.com/spacex-falcon-9-completes-static-fire-test-for-year-closing-launch/ (http://spaceflight101.com/spacex-falcon-9-completes-static-fire-test-for-year-closing-launch/)

Appears to have both fins and legs. #QED. Unless the photo posted is a file photo..

Nope, that's a pic from Iridium 2.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: old_sellsword on 12/19/2017 02:31 AM
A user on r/SpaceX is saying this core is flying expendable. Can anyone confirm this? And if its true, why? I know they are probably running out of room to store them but its still more data and more usable engines.

https://www.reddit.com/r/spacex/comments/7cgts7/iridium_next_constellation_mission_4_launch/drg64bk/

He said he got the info from a friend at Vandy. I'm still thinking it's unlikely to be going expendable, but this comment, even if the guy isn't proven reliable, might challenge that.

u/ASTRALsunder is very reliable, they’re the same user who first gave us Zuma’s name.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ZachS09 on 12/19/2017 02:34 AM
Wasn't there something on the "General SpaceX Map", https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&hl=en_US (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&hl=en_US); that mentioned where JRTI was going to be located for Iridium-NEXT F4?

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/19/2017 02:48 AM
Wasn't there something on the "General SpaceX Map", https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&hl=en_US (https://www.google.com/maps/d/viewer?mid=1wvgFIPuOmI8da9EIB88tHo9vamo&hl=en_US); that mentioned where JRTI was going to be located for Iridium-NEXT F4?

They have an FCC permit for ASDS communications.  Maybe the plan changed after they filed for that permit.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/19/2017 09:58 AM
It could just be a matter of the barge not being available for some reason.

Yes, like not returning to port at Xmas? Ok I know lots of people do work at Xmas, but if SpaceX have no plans to reuse this booster again then they may decide recovery isn't worth the cost. They've stopped cleaning boosters between uses, which is surely cheaper than an ASDS return?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Formica on 12/19/2017 10:26 AM
Assuming it is true, this would be the first time SpaceX has expended a flight proven booster, which has been a source of speculation for some time. I'm surprised they didn't pick a GTO mission to do so. (More value for the customer expending the booster for a higher supersync orbit, etc.) It will be interesting to hear the reasoning if they decide to share it with us.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AbuSimbel on 12/19/2017 11:26 AM
I think we are forgetting that SpaceX is entering a major transition time with Block 5 coming. They've engineered it for many reuses and fast turnaround. Maybe it won't be 24h from the beginning, but it seems like many dismiss the improvement by defaulting a pessimistic position, while imo it's safe to expect major impacts on the launch logistics starting Q2 2018, even if they don't even come close to the 24h turnaround.

An example: don't underestimate the possibility that the same core could launch many subsequent missions from a pad, with the refurbishment turnaround times matching the pad turnaround (skipping a few missions that fly on new cores every now and then).

The thing is, when block 5 flies and proves its refurbishment agility,  flying the previous versions no longer makes sense. Block 5 could very well be agile enough to cover every mission from the beginning, and the stock of older recovered cores would be useless. I think SpaceX is now rushing to fly every flight proven core they have and trying not to have to many <B5 cores in stock by the time B5 flies.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/19/2017 11:26 AM
Assuming it is true, this would be the first time SpaceX has expended a flight proven booster, which has been a source of speculation for some time. I'm surprised they didn't pick a GTO mission to do so. (More value for the customer expending the booster for a higher supersync orbit, etc.) It will be interesting to hear the reasoning if they decide to share it with us.

Iridium choose to go with reuse primarily to avoid further slips to their launch schedule. SpaceX have selected a booster that's available and acceptable to Iridium. If SpaceX have simply decided that the recovery cost isn't worth the benefit to them (eg no plans to reuse this booster again, with block 5 due soon) then I'm not sure the type of mission (not GTO) is particularly relevant to that decision?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 12/19/2017 11:38 AM
I suppose that it's possible that SpaceX have decided that, whilst good for launch, the condition of the condition of the booster is marginal for it to withstand EDL stresses so they've decided just not to bother.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Raul on 12/19/2017 12:11 PM
According the original plans mentioned in FCC permit, planned booster recovery position should be so far on the south, that boostback burn would be completely skipped compare to previous flight of this booster with Iridium-2 or other IridiumNEXT missions. This also implies like no enough fuel margin for normal landing by some reason.
Change of plan to expedable booster would be comprehensible in this case.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Galactic Penguin SST on 12/19/2017 12:19 PM
According the original plans mentioned in FCC permit, planned booster recovery position should be so far on the south, that boostback burn would be completely skipped compare to previous flight of this booster with Iridium-2 or other IridiumNEXT missions. This also implies like no enough fuel margin for normal landing by some reason.
Change of plan to expedable booster would be comprehensible in this case.

.....so why was the recovery position changed?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/19/2017 12:24 PM
I think people are missing an important aspect of SpaceX’s business plan, let alone corporate culture - that of reuse. I’ve posted this before.

Reuse.

I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers. I think SpaceX will only opt to throw away a core if it is absolutely the only option available.

Some people in this forum are so completely stuck in an unbendable formulaic mentality. Sometimes it’s important to step back and think about the entire thing and realize there’s also value in perception and forward thinking. 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/19/2017 12:35 PM
I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers.

If I understand you correctly, you're saying that SpaceX would spend a few 100k recovering a booster they don't need so that customers don't think they're going soft on re-use? After 20 previous successful recoveries, including the last 16 consecutive attempts? And on a flight using a flight proven booster?

I think we'll have to agree to disagree on that one.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/19/2017 12:44 PM
I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers.

If I understand you correctly, you're saying that SpaceX would spend a few 100k recovering a booster they don't need so that customers don't think they're going soft on re-use? After 20 previous successful recoveries, including the last 16 consecutive attempts? And on a flight using a flight proven booster?

I think we'll have to agree to disagree on that one.
Feel free. But I suppose with your mindset you see zero value in the returned booster. That's fine - but I see value in:

- Post flight examination of entire system
- Reuse of sub systems such as gimbal control system, hydraulic systems, grid fin actuators and the fins themselves (even if AL), engine control modules, Merlin components (at $1,000,000 for each M1D you say that getting parts off even a few engines won't cover the cost of recovery?)
- Maintaining the path that SpaceX has worked so hard to establish.


Again - disagree all you want, but I maintain it's fatally shortsighted...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: rsdavis9 on 12/19/2017 12:55 PM
I thought that the block 5 adds nothing to engine reuse? The engines are already at the pretty much maximum for reuse. Maybe the turbines are better in block 5? So 9 engines at 1M a piece seems well worth it to recover.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ATPTourFan on 12/19/2017 01:24 PM
When we first learned about the position of JRTI back in October, I suspected (http://forum.nasaspaceflight.com/index.php?topic=43940.msg1741414#msg1741414) SpaceX and Iridium compromising on the use of a flight proven booster to facilitate on on-time launch. Part of that agreement is additional margin. Now SpaceX feels recovery of this block 3 booster is just not worth it and removing legs/fins provides Iridium even greater margin for success.

Quote
My first thought was that SpaceX is giving Iridium as much margin as possible to get their payload to the proper orbit. Iridium and SpaceX worked out the arrangement to utilize the flight-proven core to help schedule this launch, but SpaceX really doesn't need to be gentle to this core as much as they MUST get Iridium-4 payload where it needs to go - maximum margins to make customer happy.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: wannamoonbase on 12/19/2017 01:43 PM
When we first learned about the position of JRTI back in October, I suspected (http://forum.nasaspaceflight.com/index.php?topic=43940.msg1741414#msg1741414) SpaceX and Iridium compromising on the use of a flight proven booster to facilitate on on-time launch. Part of that agreement is additional margin. Now SpaceX feels recovery of this block 3 booster is just not worth it and removing legs/fins provides Iridium even greater margin for success.

I think we can expect to see Block 3's and 4's refly once but that the final flight may in fact be expendable.

They've tested hot recoveries, they've collect reflown Block 3/4.  Maybe they don't need any more boosters that won't fly again.

In conclusion, All hail the mighty Block 5!!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/19/2017 01:51 PM
When we first learned about the position of JRTI back in October, I suspected (http://forum.nasaspaceflight.com/index.php?topic=43940.msg1741414#msg1741414) SpaceX and Iridium compromising on the use of a flight proven booster to facilitate on on-time launch. Part of that agreement is additional margin. Now SpaceX feels recovery of this block 3 booster is just not worth it and removing legs/fins provides Iridium even greater margin for success.

I think we can expect to see Block 3's and 4's refly once but that the final flight may in fact be expendable.

They've tested hot recoveries, they've collect reflown Block 3/4.  Maybe they don't need any more boosters that won't fly again.

In conclusion, All hail the mighty Block 5!!

I think that parts reuse and the scrap value of the raw materials in a F9 booster are probably worth the cost of recovery. But they may not be worth the lost margin if an engine or two goes out on the way up.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AbuSimbel on 12/19/2017 01:56 PM
I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers.

If I understand you correctly, you're saying that SpaceX would spend a few 100k recovering a booster they don't need so that customers don't think they're going soft on re-use? After 20 previous successful recoveries, including the last 16 consecutive attempts? And on a flight using a flight proven booster?

I think we'll have to agree to disagree on that one.
Feel free. But I suppose with your mindset you see zero value in the returned booster. That's fine - but I see value in:

- Post flight examination of entire system
- Reuse of sub systems such as gimbal control system, hydraulic systems, grid fin actuators and the fins themselves (even if AL), engine control modules, Merlin components (at $1,000,000 for each M1D you say that getting parts off even a few engines won't cover the cost of recovery?)
- Maintaining the path that SpaceX has worked so hard to establish.


Again - disagree all you want, but I maintain it's fatally shortsighted...

The fact is that SpaceX already has too many flight proven cores in storage that they have to use before block 5 flies or they become useless. 
We will see very few old cores missions after B5's maiden flight, SX will want to literally jump to B5 as fast as humanly possible.
NASA wants Block 5 flight history for Commercial Crew, SpaceX wants to fly as many B5 as they can to acquire flight history and because it's cheaper to reuse. After Block 5, flying anything but B5 essentially becomes a pain in the ass to them, they may do it for 1-2 missions but only because logistically forced. Formosat, NROL-76, OTV-5, CRS-12, Iridium-3, Koreasat (+Zuma after it lands) all have to fly before block 5. This means flying them on these possible missions: GovSat, Paz, CRS-14, Iridium-5, maybe Hispasat. After those, reusing Block 5 is much more convenient because it's easier, faster, cheaper, necessary for NASA and for SX's own reuse program.
 
They do have:
Plenty of cores already that could be stripped off the components you listed (and I haven't seen evidence it would be useful to do so, we know about engines getting swapped between cores but I don't think they're frankentseining them too much with other systems). Plenty of data on reflown boosters. Enough used cores to refly for the very few missions that require them before block 5.

What do they lack?
Storage space.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jgoldader on 12/19/2017 01:59 PM
I think that parts reuse and the scrap value of the raw materials in a F9 booster are probably worth the cost of recovery. But they may not be worth the lost margin if an engine or two goes out on the way up.

That seems like an awfully good point.  Aside from SpX and their customers, I doubt many know details of the trade space (performance/recoverability/margin) involved in the negotiations.  The mass of the recovery hardware obviously impacts both margin and recovery.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/19/2017 02:22 PM
It would be interesting if SpaceX reclaimed some of that extra margin by flying fairing recovery hardware.  Stripping the legs would free up some mass.  Trade expending the first stage for a good full-up fairing recovery test. 

I've got no info on this (other that the fairing recovery ship Mr. Steven is in Port of LA right now, isn't it? And its normal home is on the East Coast) --- but it seemed like an interesting trade one could make.

EDIT: see the new pictures of Mr. Steven at http://forum.nasaspaceflight.com/index.php?topic=37727.msg1761260.msg#1761260

Looks like my guess might be right?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: JamesH65 on 12/19/2017 02:25 PM
I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers.

If I understand you correctly, you're saying that SpaceX would spend a few 100k recovering a booster they don't need so that customers don't think they're going soft on re-use? After 20 previous successful recoveries, including the last 16 consecutive attempts? And on a flight using a flight proven booster?

I think we'll have to agree to disagree on that one.
Feel free. But I suppose with your mindset you see zero value in the returned booster. That's fine - but I see value in:

- Post flight examination of entire system
- Reuse of sub systems such as gimbal control system, hydraulic systems, grid fin actuators and the fins themselves (even if AL), engine control modules, Merlin components (at $1,000,000 for each M1D you say that getting parts off even a few engines won't cover the cost of recovery?)
- Maintaining the path that SpaceX has worked so hard to establish.


Again - disagree all you want, but I maintain it's fatally shortsighted...

Well, they have already examined many returned stages thoroughly, so I am not sure that is a valid argument.

If not reusing the whole booster, reuse of returned subsystems might have merit, if they are of use in block 5. If not, they are just so much scrap, that needs storage. Or do they just leave them out in the car park?

Maintain the path is irrelevant, Musk knows how to count and they already have an impressive track record. If the value return from bringing it back is less than dumping it, which do you think they will do?


Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/19/2017 03:26 PM
According the original plans mentioned in FCC permit, planned booster recovery position should be so far on the south, that boostback burn would be completely skipped compare to previous flight of this booster with Iridium-2 or other IridiumNEXT missions. This also implies like no enough fuel margin for normal landing by some reason.
Change of plan to expedable booster would be comprehensible in this case.

SpaceX’s track record and magic ingredient is to make progress, like developing first stage recovery, at extremely low marginal cost by piggybacking on paid launches. If they are forgoing the boostback or braking burn they will get an extremely energetic entry. A perfect opportunity to expand the envelope, from which they can best learn by recovering the first stage.

Wouldn’t we expect to see titanium grid fins if they are planning on a high speed reentry?
Either way, we will know in a few days.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/19/2017 03:29 PM
I think SpaceX are driven by cost, more than anything else. We don't have visibility to their cost numbers or the exact decision process (although maybe a tweet to Elon is in order?).

But whenever someone starts out with (in essence) "I think SpaceX made the wrong decision" I tend to start out disagreeing. Once in a while (AMOS-6) they flub. But not that often.

If this booster is not being recovered, there is surely a cost driven reason for it that made sense when they worked the trades. As AbuSimbel outlines.

These engines don't have the new impellers. That means they  may not be as valuable (it would be a big teardown to retrofit I would think) as some might suspect.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/19/2017 03:38 PM
And then this from Twitter (via the UPDATES thread):

Quote
HöchstErbaulich. @HochstErbaulich
Hey @IridiumBoss will the Falcon 9 core for Iridium-4 be recovered? There are rumors that the first stage has no recovery equipment installed.

Matt Desch @IridiumBoss
Replying to @HochstErbaulich
No, I understand it won't be

Interesting wording that supports the idea that the decision to recover or not is solely SpaceX’s and even their customers sometimes don’t know until right before launch.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Kansan52 on 12/19/2017 03:46 PM
IMO, Job One is doing the customer's mission. Sounds like this was the way they could accomplish this for Iridium.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: pb2000 on 12/19/2017 04:02 PM
With regards to reusability being a core part of SpaceX corporate culture; that really only works until they become too efficient and need to start laying off staff on the first stage production line. I'm sure the idea was to have BFR production needing staff before this became a problem, but who would have guessed the attempted recovery success would go to 100%?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/19/2017 04:13 PM
Interesting wording that supports the idea that the decision to recover or not is solely SpaceX’s and even their customers sometimes don’t know until right before launch.

I agree the decision must be SpaceX's, but I think he does know for sure about recovery it's just that he's careful not to tread onSpaceX's toes and say anything definitive that relates to them rather than the mission.

BTW his response to being asked why no recovery on this mission is:

Quote
Can't answer that.

https://twitter.com/IridiumBoss/status/943161784994811904
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: saliva_sweet on 12/19/2017 05:14 PM
If this booster is not being recovered, there is surely a cost driven reason for it that made sense when they worked the trades.

In that case we can infer that the marginal cost of ASDS recovery is greater than the value of 20 tons of space grade metals and alloys.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 12/19/2017 05:27 PM
If this booster is not being recovered, there is surely a cost driven reason for it that made sense when they worked the trades.

In that case we can infer that the marginal cost of ASDS recovery is greater than the SCRAP-value of 20 tons of space grade metals and alloys.

There, fixed that for ya.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/19/2017 06:29 PM
Interesting wording that supports the idea that the decision to recover or not is solely SpaceX’s and even their customers sometimes don’t know until right before launch.

I agree the decision must be SpaceX's, but I think he does know for sure about recovery it's just that he's careful not to tread onSpaceX's toes and say anything definitive that relates to them rather than the mission.

BTW his response to being asked why no recovery on this mission is:

Quote
Can't answer that.

https://twitter.com/IridiumBoss/status/943161784994811904
My theory is that there is a significant fairing recovery experiment planned, and he is being careful not to step on SpaceX toes and let them announce that.  The reason for no S1 recovery is to enable the not-for-me-to-announce fairing recovery experiment.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 12/19/2017 06:45 PM
If this booster is not being recovered, there is surely a cost driven reason for it that made sense when they worked the trades.

In that case we can infer that the marginal cost of ASDS recovery is greater than the SCRAP-value of 20 tons of space grade metals and alloys.

There, fixed that for ya.

Or the value of another "rocket garden" artifact.  (Either for public display in a museum or such, or for private display in or near a SpaceX facility.)

(If there is discussion on SpaceX donating equipment for display, could someone point to it?)

On the flip side, Davy Jones gets a treasure for his locker that is becoming ever rarer--an expended Falcon 9 first stage! :D
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 12/19/2017 06:55 PM
I can totally understand the economical reasons for foregoing booster recovery along with not wanting to add to the stockpile of 'old' block boosters. I'm honestly more disappointed from an environmental standpoint. Given the ability to recover, it seems a bit irresponsible to just throw the trash into the sea so to speak. I don't really know what hazards might be on board when it goes in the drink, so maybe it's just mostly stuff that doesn't matter/polute. Can they purge/consume any liquid contaminants prior to impact with the water?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/19/2017 07:10 PM
I can totally understand the economical reasons for foregoing booster recovery along with not wanting to add to the stockpile of 'old' block boosters. I'm honestly more disappointed from an environmental standpoint. Given the ability to recover, it seems a bit irresponsible to just throw the trash into the sea so to speak. I don't really know what hazards might be on board when it goes in the drink, so maybe it's just mostly stuff that doesn't matter/polute. Can they purge/consume any liquid contaminants prior to impact with the water?

What kind of wastrel throws a perfectly good rocket in the drink... :)

As for your questions, I can give you Tory Bruno's twitter ID, you can ask him what ULA is doing to mitigate this....  more seriously, purging contaminants? wouldn't those just end up in exactly the same place anyway? (or in the atmosphere)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 12/19/2017 07:37 PM
I can totally understand the economical reasons for foregoing booster recovery along with not wanting to add to the stockpile of 'old' block boosters. I'm honestly more disappointed from an environmental standpoint. Given the ability to recover, it seems a bit irresponsible to just throw the trash into the sea so to speak. I don't really know what hazards might be on board when it goes in the drink, so maybe it's just mostly stuff that doesn't matter/polute. Can they purge/consume any liquid contaminants prior to impact with the water?

What kind of wastrel throws a perfectly good rocket in the drink... :)

As for your questions, I can give you Tory Bruno's twitter ID, you can ask him what ULA is doing to mitigate this....  more seriously, purging contaminants? wouldn't those just end up in exactly the same place anyway? (or in the atmosphere)
I was specifically thinking of TEA/TEB. By purging them together they ignite and burn off rather than leaking individually into the water. I don’t know what else is on the booster. Residual helium, N2 and LOx don’t really matter. They’re inert and/or naturally occurring. The kerosene isn’t great. You could burn it to empty before impact? Any other hazardous materials onboard? Probably some heavy metals in the electronics but the amount compared to volume of ocean probably makes inconsequential. That’s likely the argument any of the launch providers use. Tiny amounts in huge oceans...therefore doesn’t matter. Probably true but that logic has been used before to justify doing things that eventually turned out to be problems.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: kevinof on 12/19/2017 07:42 PM
There is another side to the decision - they don't need the stage, they probably won't reuse it and therefore it has little or no value. However in trying to recover it, there is always a risk that the landing will fail, do a lot of damage to the barge and cost Space X a lot of money and time to repair.

If there's a risk (however small)  vs the zero value of the stage then splash it?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Wolfram66 on 12/19/2017 07:58 PM
There is another side to the decision - they don't need the stage, they probably won't reuse it and therefore it has little or no value. However in trying to recover it, there is always a risk that the landing will fail, do a lot of damage to the barge and cost Space X a lot of money and time to repair.

If there's a risk (however small)  vs the zero value of the stage then splash it?

Or possibly testing the FH Side booster engine gimbal separation sequence? IDK... throwing stuff at the wall here
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Greg Hullender on 12/19/2017 08:26 PM
I would guess that they learn a lot from each recovered stage. Information that could help them further reduce the cost of reuse, for example, or give them a better idea of how many times they can refly the same stage.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: whatever11235 on 12/19/2017 08:36 PM
I would guess that they learn a lot from each recovered stage. Information that could help them further reduce the cost of reuse, for example, or give them a better idea of how many times they can refly the same stage.

After 20 times I think they learned all they could.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: UKobserver on 12/19/2017 08:51 PM
I think we are being too absolute in our arguments;

If Elon/SpaceX have shown anything, it is that they are very pragmatic in their decision making. They are constantly weighing their wish to push on with their experimentation and evolution of their technologies against the need to do a good job for their customers and build up those relationships. Several times they have chosen to sacrifice recovery margins (making for a hotter and more damaging re-entry) or even the recovery itself in order to boost the customer into a better orbit than contractually agreed, particularly where those customers have been waiting a long time and potentially have lost income as a result.

In a similarly pragmatic way, for Iridium 4 they have traded their wish to get a first west coast RTLS under their belt for their equally strong wish to get an important, high-profile, customer to start using pre-flown boosters and get as much use as they can out of their already built and paid-for inventory.

Therefore when we hear that this mission is going to be flown expendable, and we simultaneously hear that the filed ASDS landing location shifted a long way south when they opted to switch to a re-used block 3 booster, our immediate thought out to be that they are making some sort of engineering/customer support trade here.

I think both of the two theories that have been postulated above in this vein could be true, which were;

1. That in return for re-using a pre-flown booster they have promised Matt Desch delivery to a slightly higher initial orbit, so as to reduce the time needed to raise the satellites into their final orbits, and;

2. That they may indeed have traded some or all of the recovery margin to test out something else which requires adding mass to the stage, such as a further evolution of the fairing recovery, as cscott postulated, and which is made more likely by the fairing recovery ship having been switched to the west coast. It could be that they have accepted a heavier recoverable fairing design for Block 5, but want to test it now, and can only do so on a less-powerful block 3 booster by sacrificing margin somewhere else, such as removing the weight of the landing legs and grid fins.

What I don't think we can yet conclude is that;

a) the marginal cost of recovery is greater that the scrap value of the materials in the booster. I suspect that recovery costs are actually pretty low, given how SpaceX never spends any more than they need to on their equipment. As an example compare the size and spec of their tugboats and the fairly rudimentary (simple but effective) design of their ASDS barges, compared to the gold-plated designs planned by Blue Origin. I would certainly guess that recovery is just a small fraction of the cost of actually building the booster, hence why it makes sense to recover it in the first place, but what the actual value of the materials contained within the rocket is would be hard to guess. It's not impossible that it might be less than the cost of recovery, but I don't think we can conclude that much solely from the fact that they are expending this booster. Not without further information.

b) they don't need or want to recover any more boosters. We're lacking some important information here as to how many times they wish or intend to use these older recovered boosters, and it might even be that SpaceX themselves haven't decided yet, and that it might depend on how successful their block 5 design proves to be, and how quickly they can reduce the refurbishment time of that booster. A few things to think about in that regard;

i) they have obviously felt it worthwhile to try to recover all of the boosters that have made a second flight so far. This might be just so that they could inspect them and learn more lessons about re-usability, but it might also mean that they would consider using these boosters a third time, perhaps for the initial launches of their own satellite constellation, to really reduce the capital outlay required for that.

ii) they haven't yet reflown a booster that has performed a GTO profile, but note that they have converted one of these into one of their first Falcon Heavy side boosters. We don't know how much refurbishment that required, but given the risk to LC-39A if that launch goes wrong, I think we can assume that they are completely confident in that booster being safe to refly. And if it's safe to refly that means their other landed GTO boosters might also be available for re-use, even if that has to just be for launching their own satellites, if their customers aren't comfortable with flying on them. Which means they are building up quite a stockpile of boosters, unless they have already quietly started scrapping some of them. So it's possible that in Adelaide when Elon talked about building up a stock of boosters, he may have also meant some of the older block 3 and 4 stages, which they could use to loft some of their Starlink constellation.

iii) As AbuSimbel points out; they wont want to waste precious time and resources refurbishing more demanding older boosters if they think they have more block 5 flight lifetimes available than they could ever use, but given that they can't be certain exactly when BFR/BFS will be ready to assume the full launch workload it's also possible that they will choose to eke out every last flight they can get out of the block 3 and 4 boosters, in order to be keep as many block 5 flights in reserve as they can. It could also simply be good business, if the cost of those refurbishments is sufficiently low.

So taking all the above into account, it's possible that SpaceX are still keen to recover and stockpile even more boosters, and that the decision not to this time is simply a trade to allow them to achieve something else instead.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/19/2017 09:10 PM
welcome to the forum, UKobserver.  Great first post. I think you nicely synthesized a lot of the previous speculation into one nice easy to digest package of analysis.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: saliva_sweet on 12/19/2017 09:36 PM
1. That in return for re-using a pre-flown booster they have promised Matt Desch delivery to a slightly higher initial orbit, so as to reduce the time needed to raise the satellites into their final orbits, and;

2. That they may indeed have traded some or all of the recovery margin to test out something else which requires adding mass to the stage, such as a further evolution of the fairing recovery, as cscott postulated, and which is made more likely by the fairing recovery ship having been switched to the west coast. It could be that they have accepted a heavier recoverable fairing design for Block 5, but want to test it now, and can only do so on a less-powerful block 3 booster by sacrificing margin somewhere else, such as removing the weight of the landing legs and grid fins.

We know that Iridium flights are RTLS-able on block 4 (which AFAIK wasn't supposed to be much more powerful than block 3). That would imply that the recoverable fairing comes with a huge penalty if they need to fly block 3 expendably with it. There is also some L2 info that suggests that deals with Desch or margins are unlikely to be behind this decision.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/19/2017 10:00 PM
As funny as this sounds could the reason for the expended booster be they are running out of storage?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/19/2017 10:06 PM
As funny as this sounds could the reason for the expended booster be they are running out of storage?

That's possible, but it's mostly to clear out the old Block III boosters to make way for Block IV and V.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/19/2017 10:14 PM
Another thing I am interested in seeing is what this will look like. Desch mentioned in a tweet this would have the soot from its last landing and minus the legs and fins, should be very interesting
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mme on 12/19/2017 10:25 PM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
It's disappointing to me but how is expending a booster you plan to never use again confusing to people?  I'd prefer they recover it and analyze/recycle it. But they didn't ask me.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AncientU on 12/19/2017 11:17 PM
I don’t see SpaceX tossing away a booster just because they don’t need it. That runs exactly opposite of the mindset they’re trying to establish. A few $100k to recover a core is absolutely nothing in the larger framework of mission cost - compare that to the value of underscoring the important of recovery and reuse to their customers.

If I understand you correctly, you're saying that SpaceX would spend a few 100k recovering a booster they don't need so that customers don't think they're going soft on re-use? After 20 previous successful recoveries, including the last 16 consecutive attempts? And on a flight using a flight proven booster?

I think we'll have to agree to disagree on that one.
Feel free. But I suppose with your mindset you see zero value in the returned booster. That's fine - but I see value in:

- Post flight examination of entire system
- Reuse of sub systems such as gimbal control system, hydraulic systems, grid fin actuators and the fins themselves (even if AL), engine control modules, Merlin components (at $1,000,000 for each M1D you say that getting parts off even a few engines won't cover the cost of recovery?)
- Maintaining the path that SpaceX has worked so hard to establish.


Again - disagree all you want, but I maintain it's fatally shortsighted...

Could be that they believe that they are at point of diminishing returns on examining earlier-than-Block 5 boosters. 
That's great news (if it is true).

Certainly a reason to not expend more funds and time...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AncientU on 12/19/2017 11:25 PM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle

You so want to be right about the folly of reusable boosters... but you're not.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: wannamoonbase on 12/20/2017 12:07 AM
As funny as this sounds could the reason for the expended booster be they are running out of storage?

That's possible, but it's mostly to clear out the old Block III boosters to make way for Block IV and V.

Bingo.  It’s not a first flight booster.  This makes sense given they are only flying each booster 2 times right now.

Recovery is cool, but it Takes considerable resources (maybe a million or two) and they don’t need them piling up.  So why not give Iridium the most boost possible.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/20/2017 12:08 AM
Quote
SpaceX spokesperson confirms online discussions (and comments by @IridiumBoss ) there will be no attempt to land the Falcon 9 first stage on Friday’s launch. “These are case by case decisions and are based on mission requirements and the needs of our manifest.”

https://twitter.com/jeff_foust/status/943269599302127617 (https://twitter.com/jeff_foust/status/943269599302127617)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Arb on 12/20/2017 12:12 AM
If there is discussion on SpaceX donating equipment for display, could someone point to it?
Can't provide a reference (it was some years ago) but my recollection is that when asked about donating a recovered core to the National Air and Space Museum, Musk replied along the lines of "Sure, if they pay for it".
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/20/2017 12:14 AM
On the flip side, i wanna hear what you all think about the new equipment added on mr. steven, i think its (obviously) for fairing recover, but the big poles that have been installed are interesting, I personally think a net will be installed and the fairing will parachute on to it, if this is the case, i hope it is shown on the webcast

all credit to reddit user vshie
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: craigcocca on 12/20/2017 12:52 AM
Mr Steven is still in port  as of the timestamp of this post
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/20/2017 01:11 AM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
You so want to be right about the folly of reusable boosters... but you're not.
I've never called it "folly".  They may well be on a path to making partial reuse pay, eventually, but what I have been saying is that they are not there yet.  Throwing away a first stage on purpose during only its second flight (both lower energy LEO missions, BTW) is proof. 

 - Ed Kyle
it's proof of nothing other than a relentless focus on cost.

It's a block 3. So last week. Old engines. They are swimming in cores and don't need it. Only you could turn an actual advantage into your apparent disadvantage.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: kirghizstan on 12/20/2017 01:12 AM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
You so want to be right about the folly of reusable boosters... but you're not.
I've never called it "folly".  They may well be on a path to making partial reuse pay, eventually, but what I have been saying is that they are not there yet.  Throwing away a first stage on purpose during only its second flight (both lower energy LEO missions, BTW) is proof. 

 - Ed Kyle


What if they are simply moving away from supporting that F9 block in the interest of commonality?  That block might have higher reuse costs and in the long run they have no use for continuing to support it. 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/20/2017 01:13 AM
On the flip side, i wanna hear what you all think about the new equipment added on mr. steven, i think its (obviously) for fairing recover, but the big poles that have been installed are interesting, I personally think a net will be installed and the fairing will parachute on to it, if this is the case, i hope it is shown on the webcast

all credit to reddit user vshie

The place to discuss that is the Fairing Reuse thread. http://forum.nasaspaceflight.com/index.php?topic=37727
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/20/2017 01:20 AM
Ah, thanks!


On the flip side, i wanna hear what you all think about the new equipment added on mr. steven, i think its (obviously) for fairing recover, but the big poles that have been installed are interesting, I personally think a net will be installed and the fairing will parachute on to it, if this is the case, i hope it is shown on the webcast

all credit to reddit user vshie

The place to discuss that is the Fairing Reuse thread. http://forum.nasaspaceflight.com/index.php?topic=37727
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/20/2017 01:24 AM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
You so want to be right about the folly of reusable boosters... but you're not.
I've never called it "folly".  They may well be on a path to making partial reuse pay, eventually, but what I have been saying is that they are not there yet.  Throwing away a first stage on purpose during only its second flight (both lower energy LEO missions, BTW) is proof. 

 - Ed Kyle
There is no evidence that even just 2 launches per booster wouldn't quickly pay back the initial investment in reuse. If they save $20M net per reuse, they are already at $100M saved in only 8 months, with the reuse rate rapidly increasing.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/20/2017 01:29 AM
General reuse economics is probably off topic here. I think there's a tread called Economics of Reuse or something.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/20/2017 01:30 AM
If there is discussion on SpaceX donating equipment for display, could someone point to it?
Can't provide a reference (it was some years ago) but my recollection is that when asked about donating a recovered core to the National Air and Space Museum, Musk replied along the lines of "Sure, if they pay for it".
There are at least three recovered boosters on display (or planned to be): one outside SpaceX hq in Hawthorne, one for the KSC rocket garden ("in the next few months" I was told when I was there this summer), and one outside the SpaceX launch and landing control center across (and up the road) from Fishlips in Port Canaveral.  Other than the one in the KSC rocket garden, all are free and accessible by the public.

Ob. on-topic note: no recovery doesn't necessarily mean no grid fins.

I wouldn't be surprised to see Ti grid fins on this flight, in fact.

Also: different iridium flights are heading to different orbits with different inclinations.  Good margins for flight #1 don't *necessarily* mean the margins on flight #4 are large.

EDIT: all iridium satellites are in the same inclination, just different phasing.  They have different hosted payloads, but I don't know if that's enough mass to be significant for this discussion.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Jcc on 12/20/2017 01:31 AM
Ok, so we have some theories about expending the booster because they don't need it, don't have a place to store it, etc., and some thought about doing something extraordinary in terms of fairing recovery that requires the performance or maybe the ships.

 Then there's the question of them actually needing the extra performance for contractual reasons, because they promised a higher orbit to reduce time to get the satellites into service. What about orbital plane, will this set of satellites require a greater plane change?

We may learn more once the press kit is released, if it has first stage burn time and target orbits that show the need for more performance.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 12/20/2017 01:44 AM
I was under the impression that all the satellites in the constellation were at the same inclination but in different planes/phases. Why would these require more performance than previous missions. Higher orbit maybe but they can’t get that close to the operating orbit before risking a collision as the orbit are already populated. I also thought I remember that all of these sats in this launch were headed to the same plane except two that were planned as on orbit spares in different planes.

I’m a total amateur with this orbit stuff so it is entirely possible I’ve massively misunderstood something. The hazard areas seem largely consistent from launch to launch, though, which also has me thinking these launches are all very similar in performance requirements.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Steven Pietrobon on 12/20/2017 04:17 AM
I'm puzzled by SpaceX's decision to expend this booster. We know from previous Iridium flights that the vehicle has enough performance for it to be recovered. If I had an excess of obsolete boosters, I wouldn't expend them on missions where they can be reused, like in this flight. I would save them for those missions where they have to be expended, like in high performance GTO missions.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: pathfinder_01 on 12/20/2017 04:31 AM
I'm puzzled by SpaceX's decision to expend this booster. We know from previous Iridium flights that the vehicle has enough performance for it to be recovered. If I had an excess of obsolete boosters, I wouldn't expend them on missions where they can be reused, like in this flight. I would save them for those missions where they have to be expended, like in high performance GTO missions.

Not really. There are costs associated with supporting an older model of booster and this one likely has maybe one more mission left in it. Given they have to build block V for commercial crew and given the likely limited storage, over supply of boosters and likely greater cost to refurbish getting rid of block III makes sense.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hopalong on 12/20/2017 05:15 AM
I'm puzzled by SpaceX's decision to expend this booster. We know from previous Iridium flights that the vehicle has enough performance for it to be recovered. If I had an excess of obsolete boosters, I wouldn't expend them on missions where they can be reused, like in this flight. I would save them for those missions where they have to be expended, like in high performance GTO missions.

Not really. There are costs associated with supporting an older model of booster and this one likely has maybe one more mission left in it. Given they have to build block V for commercial crew and given the likely limited storage, over supply of boosters and likely greater cost to refurbish getting rid of block III makes sense.

My initial thoughts where the same as Steven's, that they would look to expend the last block III's and IV's on high energy missions. But this one is on the wrong coast as the high energy missions are launched from the cape. So another factor to include in the calculation is the cost of shipping the core across the States. It can't be cheap to move a core across the country.

IMHO, expending this core shows that SpaceX is a pragmatic company as well as a visionary one.

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 12/20/2017 06:18 AM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
It's disappointing to me but how is expending a booster you plan to never use again confusing to people?  I'd prefer they recover it and analyze/recycle it. But they didn't ask me.

They don't need to analyse it. They have already recovered (and analyzed) boosters 20 times, 3 of them being re-flights. SpaceX right now has a huge database on booster wear-and-tear, and the information in that database has been essential for informing the design of Falcon 9 Block 5. In stead of analyzing yet another old Block 3 it is time to get the first Block 5 off the ground and validate its design.

One of the essentials of working agile (like SpaceX does) is never to get stuck in the past. Always move forward. That's what SpaceX is doing. Block 3 has been analyzed to death and is yesterday's booster. Time to let go of it.
Also, it doesn't help that SpaceX has no storage space for all those old booster. They've already begun dumping some of them in the boneyard section of McGregor.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: MikeAtkinson on 12/20/2017 07:00 AM
We know that SpaceX perform minor experiments on most flights, especially after the main mission is complete. Perhaps on these next two flights the experiments mean that recovery is unlikely. I'm thinking things like multiple second stage relights after release of the satellites or high angle of attack reentries.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 12/20/2017 07:16 AM
My guess is that, if the reason is performance-based, we need to look for this mission to have a lot higher-energy insertion orbit for some reason. Maybe a combination of launch date (which must have moved a few times) and schedule pressure (I understand that Iridium needs the entire constellation launched by the end of H1-2018) which leads this launch to be at a non-optimal time and requiring more energy to get the satellites to the desired orbit.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: chalz on 12/20/2017 10:45 AM
A reusable booster is always going to fly as expendable on its last flight, no matter how long or short its flight history. It will keep happening until some financial penalty is applied for dropping this specific type of industrial waste in the ocean. Until then even a tiny cost to return the booster is greater than zero cost of letting it drop.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AbuSimbel on 12/20/2017 10:56 AM
A reusable booster is always going to fly as expendable on its last flight, no matter how long or short its flight history. It will keep happening until some financial penalty is applied for dropping this specific type of industrial waste in the ocean. Until then even a tiny cost to return the booster is greater than zero cost of letting it drop.

I think the people at SpaceX really want to be better than that.
Once reuse matures and the boosters fly many missions I expect them to properly retire their beaten workhorses.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 12/20/2017 11:14 AM
A reusable booster is always going to fly as expendable on its last flight, no matter how long or short its flight history. It will keep happening until some financial penalty is applied for dropping this specific type of industrial waste in the ocean. Until then even a tiny cost to return the booster is greater than zero cost of letting it drop.

That depends on a lot of factors. It's quite possible that SpaceX will want to take units at the end of their fatigue life and cannibalise them for both scrap parts as well as rare alloys  that can be returned to their suppliers for re-smelting and re-forging.

I maintain my opinion that the expending of this booster on this flight is entirely a performance issue: the customer's target orbit leaves insufficient propellent margins for even a drone ship recovery.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: codav on 12/20/2017 11:47 AM
My guess is that, if the reason is performance-based, we need to look for this mission to have a lot higher-energy insertion orbit for some reason.

This is most probably not the case, Iridium satellites all go into almost the same orbit (polar, ~780km altitude for active satellites, 666km for spares), with a small height difference between each plane to avoid collisions over the poles. All previous launches deployed at around 680km, the satellites then perform the insertion into their respective final orbit, some even change the plane using orbital precession to assist with it, which takes a few months.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: JamesH65 on 12/20/2017 12:06 PM
A reusable booster is always going to fly as expendable on its last flight, no matter how long or short its flight history. It will keep happening until some financial penalty is applied for dropping this specific type of industrial waste in the ocean. Until then even a tiny cost to return the booster is greater than zero cost of letting it drop.

That depends on a lot of factors. It's quite possible that SpaceX will want to take units at the end of their fatigue life and cannibalise them for both scrap parts as well as rare alloys  that can be returned to their suppliers for re-smelting and re-forging.

Only if the cost of recovering is less than the gains made by reuse. And we have no idea of the figures involved.

To me, this just seems to be a "We don't need this booster to come back" because a) we'll never use it b) We have no place to store it c) recovery costs exceed scrap value d) We'll have Block 5 soon making all previous models obsolete (see a) e) the longer we keep flying these older boosters, the longer before we start using block 5 which is cheaper
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Darga on 12/20/2017 12:23 PM
I'm puzzled by SpaceX's decision to expend this booster. We know from previous Iridium flights that the vehicle has enough performance for it to be recovered. If I had an excess of obsolete boosters, I wouldn't expend them on missions where they can be reused, like in this flight. I would save them for those missions where they have to be expended, like in high performance GTO missions.

Maybe they are expending it because JRTI is down for some reason and they cant RTLS yet.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: sevenperforce on 12/20/2017 12:37 PM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
You so want to be right about the folly of reusable boosters... but you're not.
I've never called it "folly".  They may well be on a path to making partial reuse pay, eventually, but what I have been saying is that they are not there yet.  Throwing away a first stage on purpose during only its second flight (both lower energy LEO missions, BTW) is proof. 

 - Ed Kyle
This will be its third flight. Also, this is a polar orbit, on the higher end of LEO energies.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/20/2017 12:41 PM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
You so want to be right about the folly of reusable boosters... but you're not.
I've never called it "folly".  They may well be on a path to making partial reuse pay, eventually, but what I have been saying is that they are not there yet.  Throwing away a first stage on purpose during only its second flight (both lower energy LEO missions, BTW) is proof. 

 - Ed Kyle
This will be its third flight. Also, this is a polar orbit, on the higher end of LEO energies.
Third?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: sevenperforce on 12/20/2017 12:44 PM
This will be its third flight. Also, this is a polar orbit, on the higher end of LEO energies.
Third?
Whoops, my mistake. I read something wrong, earlier in the thread.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Cheapchips on 12/20/2017 12:50 PM
Maybe they're using the extra margin for 2nd stage experiments?

(I'm not proposing anything exotic)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hektor on 12/20/2017 01:15 PM
Maybe they could find a museum ready to provide it a new home ?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jpo234 on 12/20/2017 01:31 PM


So why not give Iridium the most boost possible.

That's not a GEO launch. The satellites go to their initial orbit and don't need any additional boost beyond that.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/20/2017 02:16 PM
I guess the launch log entry for this will be "the one where Elon murdered the booster"  ::)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 12/20/2017 02:25 PM
If only we had a reporter on this site who could ask SpaceX and get a direct answer to the question of why they are expending the booster.

Oh, wait: https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: LouScheffer on 12/20/2017 02:26 PM
Expend the booster to save money.  Hmmmm. 

Exactly!  With recoverable rockets, there are factors in play that never occur with expendables:
 * Storage costs
 * Refurbishment costs
 * Inventory management
 * Technical improvement of new versions vs lower cost of old versions.
The phrase "paradigm shift" is overused, but I think this is a legitimate example.

Every other transportation industry - trucking, rental cars, air transport, constantly balances these factors.   And at some point it's cheaper to expend than to keep.

Take air transport, for example.  Airlines hate to store planes they are not using.  They cost money and create no revenue, so they dispose of them as quickly as possible.  Airlines worry a great deal about refurbishment costs - that's exactly why they dispose of them right before a costly D check.  They worry about inventory - they will, for example, get rid of all their MD-80s so they can fly just one plane, a 737 (made up example).  They get rid of old planes that are working perfectly well since newer ones have better fuel economy.  But even though disposing of a plane is sometimes a way to save money, they still use each airplane more than once.  It's not a contradiction.

Note that every one of these concerns is now very relevant to SpaceX.  Boosters cost money to store, money and effort to refurbish, a mix of Block 3,4 and 5 creates headaches, and the new Block 5s offer better performance and re-use.  So sometimes SpaceX will indeed save money by throwing one away.  It's a sign that SpaceX is now operationally bracketing the economics of re-use.  Is it at least sometimes cheaper to re-use?  Apparently, since they keep doing it.   Is is always cheaper to re-use?  No, as there are costs to re-use as well.   To me, this is a strong sign that SpaceX is treating re-use as economic exercise, and not a religious rite. 

Ironically, tossing a booster every so often strongly implies that re-use is economically justified.  It means they have no philosophical, practical, or operational reasons to avoid splashing them. So when they choose to re-use them, they must believe the advantages outweigh the costs.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/20/2017 02:27 PM

Matt Desch refutes specific suggestions made to him of something different about NEXT 4 orbits:


Quote
Wrong guess. ;-) We are polar and need no doglegs, thank you!
https://twitter.com/IridiumBoss/status/943212004646539265 (https://twitter.com/IridiumBoss/status/943212004646539265)

Hmm, not sure if this is implying that there might be a different, correct guess ... ?!


It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment (see the pictures posted of fairing recovery ship GO Mr. Steven in the Port of LA), but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/20/2017 02:32 PM
It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment (see the pictures posted of fairing recovery ship GO Mr. Steven in the Port of LA), but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.

It's really not clear to me that expending the booster has anything to do with fairing recovery.  In fact, I think that is pretty far fetched.  It also has nothing to do with the payload or orbit, it's the same payload and orbit as the last three Iridium launches.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FinalFrontier on 12/20/2017 02:33 PM
Expend the booster to save money.  Hmmmm. 

Exactly!  With recoverable rockets, there are factors in play that never occur with expendables:
 * Storage costs
 * Refurbishment costs
 * Inventory management
 * Technical improvement of new versions vs lower cost of old versions.
The phrase "paradigm shift" is overused, but I think this is a legitimate example.

Every other transportation industry - trucking, rental cars, air transport, constantly balances these factors.   And at some point it's cheaper to expend than to keep.

Take air transport, for example.  Airlines hate to store planes they are not using.  They cost money and create no revenue, so they dispose of them as quickly as possible.  Airlines worry a great deal about refurbishment costs - that's exactly why they dispose of them right before a costly D check.  They worry about inventory - they will, for example, get rid of all their MD-80s so they can fly just one plane, a 737 (made up example).  They get rid of old planes that are working perfectly well since newer ones have better fuel economy.  But even though disposing of a plane is sometimes a way to save money, they still use each airplane more than once.  It's not a contradiction.

Note that every one of these concerns is now very relevant to SpaceX.  Boosters cost money to store, money and effort to refurbish, a mix of Block 3,4 and 5 creates headaches, and the new Block 5s offer better performance and re-use.  So sometimes SpaceX will indeed save money by throwing one away.  It's a sign that SpaceX is now operationally bracketing the economics of re-use.  Is it at least sometimes cheaper to re-use?  Apparently, since they keep doing it.   Is is always cheaper to re-use?  No, as there are costs to re-use as well.   To me, this is a strong sign that SpaceX is treating re-use as economic exercise, and not a religious rite. 

Ironically, tossing a booster every so often strongly implies that re-use is economically justified.  It means they have no philosophical, practical, or operational reasons to avoid splashing them. So when they choose to re-use them, they must believe the advantages outweigh the costs.

In this case its simply this one

 * Inventory management

Block 3 is already obsolete by one generation, soon to be by two generations. There is no reason to retain Block 3 boosters.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: stcks on 12/20/2017 02:37 PM
It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment (see the pictures posted of fairing recovery ship GO Mr. Steven in the Port of LA), but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.

That logic just doesn't make sense. The Iridium missions are not on the edge of recoverability like a 5.5mt GTO mission. There is margin enough to perform a boostback, long re-entry burn and a single engine landing burn. In addition, fairing recovery has been attempted on heavy GTO missions before.. with recovery hardware. The recovery hardware would have to be extremely dense and heavy in order to affect the launch so drastically that expendable F9 performance would be required. It doesn't add up.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Andy Smith on 12/20/2017 02:39 PM
Or it’s a combination of inventory management and the proposed second stage recovery experiment which is now unlikely to be taking place on FH?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/20/2017 02:42 PM
There was a comment on Reddit referencing a comment by The Roadie on Facebook saying the west coast ASDS isn't even operational right now (something about scavenging parts to repair the east coast ASDS after the fire.)  That and inventory management are far more likely reasons for expending the booster.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/20/2017 03:28 PM
Hey, you guys may be totally right. Maybe I'm putting the cart before the horse and the JRtI issues are the cause, and the experiments are how SpaceX is making lemonade from its lemons.

I still think the experiments are the reason @IridiumBoss is being coy in his responses, though.  He knows a bit more about the lemonade than he can say.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/20/2017 03:36 PM
I still think the experiments are the reason @IridiumBoss is being coy in his responses, though.  He knows a bit more about the lemonade than he can say.

Matt isn't being "coy" in his responses.  First stage recovery isn't his business.  It's not something he would talk about.  His replies said that his payload isn't the reason for expending the booster.  That is all he would be expected to say on the subject.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: zubenelgenubi on 12/20/2017 03:46 PM
If there is discussion on SpaceX donating equipment for display, could someone point to it?
Can't provide a reference (it was some years ago) but my recollection is that when asked about donating a recovered core to the National Air and Space Museum, Musk replied along the lines of "Sure, if they pay for it".

If true, what a great way to unnecessarily burn a bridge, Elon. :(

Besides, with a donation of this scale, one should get two big, juicy, high-profile public events at the museum--one public, one private--commemorating the donation/display of the new artifact.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/20/2017 03:50 PM
I still think the experiments are the reason @IridiumBoss is being coy in his responses, though.  He knows a bit more about the lemonade than he can say.

Matt isn't being "coy" in his responses.  First stage recovery isn't his business.  It's not something he would talk about.  His replies said that his payload isn't the reason for expending the booster.  That is all he would be expected to say on the subject.

As I noted, we fans are badgering him about it, and he is taking it all with very good graces (he was polite in his reply to me), because he's a good guy. I thinl he gets that we fans are excited and curious and want to put it all together from the few puzzle pieces we can see. So he's being helpful.... but he is saying no more than it is his place to say. Good on him. He's a good man who is a staunch friend of SpaceX.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: nacnud on 12/20/2017 04:04 PM
There was a comment on Reddit referencing a comment by The Roadie on Facebook saying the west coast ASDS isn't even operational right now (something about scavenging parts to repair the east coast ASDS after the fire.)  That and inventory management are far more likely reasons for expending the booster.

That makes sense, it could also be a good use of the Block 3 boosters going forwards, i.e. if you have to expend a booster because the recovery assets are down send a Block 3.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: rabe0070 on 12/20/2017 04:22 PM
If only we had a reporter on this site who could ask SpaceX and get a direct answer to the question of why they are expending the booster.

Oh, wait: https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371

I'm confused why this response was not sufficient and we are still talking about why they are not recovering it. Maybe they are using this opportunity to test something, but the main reason is to clear out Block 3 inventory.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/20/2017 04:26 PM


So why not give Iridium the most boost possible.

That's not a GEO launch. The satellites go to their initial orbit and don't need any additional boost beyond that.

They might, if an engine goes out on the way up. See CRS-1. Not likely, but it never hurts to have extra margins. Margin on the way up is a lot more useful than an old booster in a scrapyard.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/20/2017 04:40 PM
If only we had a reporter on this site who could ask SpaceX and get a direct answer to the question of why they are expending the booster.

Oh, wait: https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371 (https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371)

Of please, please, please!
Enough of this back and forth. No one is saying anything new.
Can we please let it rest until a direct source tells us which of these theories is good and which are bogus?
Let’s trust Chris G to ask this question so it gets answered.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mme on 12/20/2017 04:48 PM
Expend the booster to save money.  Hmmmm. 

 - Ed Kyle
It's disappointing to me but how is expending a booster you plan to never use again confusing to people?  I'd prefer they recover it and analyze/recycle it. But they didn't ask me.

They don't need to analyse it. They have already recovered (and analyzed) boosters 20 times, 3 of them being re-flights. SpaceX right now has a huge database on booster wear-and-tear, and the information in that database has been essential for informing the design of Falcon 9 Block 5. In stead of analyzing yet another old Block 3 it is time to get the first Block 5 off the ground and validate its design.

One of the essentials of working agile (like SpaceX does) is never to get stuck in the past. Always move forward. That's what SpaceX is doing. Block 3 has been analyzed to death and is yesterday's booster. Time to let go of it.
Also, it doesn't help that SpaceX has no storage space for all those old booster. They've already begun dumping some of them in the boneyard section of McGregor.
I agree 100%.  Block 3 is dead.  Long live Block 5.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mme on 12/20/2017 04:54 PM
If only we had a reporter on this site who could ask SpaceX and get a direct answer to the question of why they are expending the booster.

Oh, wait: https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371 (https://forum.nasaspaceflight.com/index.php?topic=44273.msg1761371#msg1761371)

Of please, please, please!
Enough of this back and forth. No one is saying anything new.
Can we please let it rest until a direct source tells us which of these theories is good and which are bogus?
Let’s trust Chris G to ask this question so it gets answered.
We don't need to go back and forth, it's answered in abaddon's link above.  Quoting it because abaddon just lined and people don't always follow links.

Matt Desch confirms no booster recovery.åç
https://twitter.com/IridiumBoss/status/943153072850776064 (https://twitter.com/IridiumBoss/status/943153072850776064)


Quote
HöchstErbaulich @HochstErbaulich
Hey @IridiumBoss will the Falcon 9 core for Iridium-4 be recovered? There are rumors that the first stage has no recovery equipment installed.

Matt Desch @IridiumBoss
Replying to @HochstErbaulich
No, I understand it won't be

For context, I'm told this is due to a desire to start clearing the Block 3 booster stock in favor for Block 4s and eventual Block 5s
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jpo234 on 12/20/2017 05:16 PM




So why not give Iridium the most boost possible.

That's not a GEO launch. The satellites go to their initial orbit and don't need any additional boost beyond that.

They might, if an engine goes out on the way up. See CRS-1. Not likely, but it never hurts to have extra margins. Margin on the way up is a lot more useful than an old booster in a scrapyard.

So you suggest that SpaceX plans to expend the booster because they think that they might lose an engine on this flight?

I very much doubt that this is the reason.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/20/2017 05:32 PM




So why not give Iridium the most boost possible.

That's not a GEO launch. The satellites go to their initial orbit and don't need any additional boost beyond that.

They might, if an engine goes out on the way up. See CRS-1. Not likely, but it never hurts to have extra margins. Margin on the way up is a lot more useful than an old booster in a scrapyard.

So you suggest that SpaceX plans to expend the booster because they think that they might lose an engine on this flight?

I very much doubt that this is the reason.

They might lose an engine leading to a performance shortfall. Leaving off the recovery hardware increases the margins available for the primary mission. Those are both facts. That those facts influenced the decision to not recover is just my opinion. There are obviously other reasons as well, and most likely no single deciding factor.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: loki on 12/20/2017 07:00 PM
Considering Spacex’s inner culture about reducing costs wherever are possible, I don’t believe they expand any booster for no reason, even if it can't be launched again. I think they have made an agreement with Iridium to move one or more satellites from this launch to adjacent orbital plane, made up for delays and for launches with flight proven busters.
Putting the customer first.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: kdhilliard on 12/20/2017 07:49 PM
Considering Spacex’s inner culture about reducing costs wherever are possible, I don’t believe they expand any booster for no reason, even if it can't be launched again. I think they have made an agreement with Iridium to move one or more satellites from this launch to adjacent orbital plane, made up for delays and for launches with flight proven busters.
Putting the customer first.

You are welcome to think that, but Matt Desch disagrees:
...
Quote
There were some speculations that the one satellite that is about to drift from Plane 2 to Plane 1 could do it a bit faster with a bit of help from Falcon 9. So this is not the case, right? ;)
https://twitter.com/Elthiryel/status/943212600594231307 (https://twitter.com/Elthiryel/status/943212600594231307)

Quote
Interesting concept! But no.
https://twitter.com/IridiumBoss/status/943287335432712192 (https://twitter.com/IridiumBoss/status/943287335432712192)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/20/2017 08:32 PM
If there is discussion on SpaceX donating equipment for display, could someone point to it?
Can't provide a reference (it was some years ago) but my recollection is that when asked about donating a recovered core to the National Air and Space Museum, Musk replied along the lines of "Sure, if they pay for it".

If true, what a great way to unnecessarily burn a bridge, Elon. :(

Besides, with a donation of this scale, one should get two big, juicy, high-profile public events at the museum--one public, one private--commemorating the donation/display of the new artifact.
Yes, so far as I too recall, it is an accurate representation.  Though, I believe it may have been specifically about the Smithsonian (Air & Space) and not necessarily a blanket statement for all collections.  Plus, I always read Elon's position as being that SpaceX was intending to get further use out of the boosters by reflying them.  So, donating one would potentially have a significant opportunity cost.  Ergo, if a museum wanted one they would need to pay for it.  But that statement was also made a few years before they'd gotten reuse to work.  Given the current situation (an abundance of booster riches), it wouldn't surprise me if that position has at least altered somewhat.  Maybe now all he'd insist on the museum paying is (a portion of?) transportation costs for an older block booster that won't be reused and already has had everything useful taken out of it.  Plus, it's clear that they are willing to give some away.  I've read comments that both KSC and CCAFS are supposed to get one.  Whether other museums have contacted SpaceX or not, I don't know.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/20/2017 08:41 PM
KSC rocket garden and CCAFS outside the SpaceX launch and landing center (thus open to the public).  Plus the one already in Hawthorne, also open to the public.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/20/2017 09:09 PM
I think the Smithsonian was looking for SpaceX to pay not just for transport but for construction of a significant new gallery or exhibit complex (these boosters are big, and the Smithsonian doesn't do second rate displays) and I don't think Elon (driven by cost) thought that was a good use of SpaceX funds at the time.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Darga on 12/20/2017 09:13 PM
I think the Smithsonian was looking for SpaceX to pay not just for transport but for construction of a significant new gallery or exhibit complex (these boosters are big, and the Smithsonian doesn't do second rate displays) and I don't think Elon (driven by cost) thought that was a good use of SpaceX funds at the time.

This is what I recall as well.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: russianhalo117 on 12/20/2017 10:17 PM
I think the Smithsonian was looking for SpaceX to pay not just for transport but for construction of a significant new gallery or exhibit complex (these boosters are big, and the Smithsonian doesn't do second rate displays) and I don't think Elon (driven by cost) thought that was a good use of SpaceX funds at the time.

This is what I recall as well.
Same situation with the Saturn era SRM at the Former Aerjoet Dade test site. Smithsonian called dibs but wanted then Gencorp to pay all costs for inerting, sealing, transport and preservation of the long spent and water filled motor.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: dorkmo on 12/21/2017 02:14 AM
maybe theyre going to try some recovery stuff with stage2? no body has shot down that idea yet  8)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/21/2017 02:19 AM
maybe theyre going to try some recovery stuff with stage2? no body has shot down that idea yet  8)

Maybe just controlled (but burning up) reentry, approaching this slowly.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/21/2017 02:36 AM
The cost of recovering a booster at sea that you're willing to not re-fly for whatever reason vs. the value it has a display article, etc?  That's a lopsided value proposition.  Now maybe an end-of-life booster for which the mission allows a RTLS...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/21/2017 03:04 AM
Recycled Rocket Ready to Fly from Vandenberg Air Force Base

https://www.noozhawk.com/article/recycled_rocket_ready_to_fly_from_vandenberg_air_force_base (https://www.noozhawk.com/article/recycled_rocket_ready_to_fly_from_vandenberg_air_force_base)

(https://www.noozhawk.com/images/uploads/Dec-2017-Iridium-Next1-cont-1000.jpg)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Steven Pietrobon on 12/21/2017 05:02 AM
SpaceX should be able to claim the cost of the booster as a tax deduction if it is donated to a museum. That's why SpaceShip One ended up in the Smithsonian, instead of taking up tourists.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lars-J on 12/21/2017 06:12 AM
SpaceX should be able to claim the cost of the booster as a tax deduction if it is donated to a museum. That's why SpaceShip One ended up in the Smithsonian, instead of taking up tourists.

Spaceship One did not fly tourists because it was too unstable and dangerous... that’s why it was retired immediately, a tax deduction was not a major factor.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/21/2017 02:41 PM
I hope you guys are prepared for them to do the exact same thing on another mission.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: NX-0 on 12/21/2017 02:51 PM
I can't believe they are just going to dump all that historic hardware and precious metals into the ocean. What a waste!

Until two years ago today, that's about all that was ever done with everything except SRB's and shuttle orbiters. That's the current plan, going forward, with every orbital rocket booster now in use or in production.

How far we have come....
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/21/2017 03:02 PM
I hope you guys are prepared for them to do the exact same thing on another mission.

SpaceX expending end-of-life or obsolete boosters on their final mission has been speculated about extensively here. Usually in the context of customers getting expendable performance for flight-proven prices - but if a customer needs a launch ASAP and an EOL or obsolete booster is the first thing available, I wouldn't be surprised at all to see it happen again.

Edit - spelling is hard.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Brian45 on 12/21/2017 05:25 PM
When they attempt a fairing recovery on this mission, which thread would that be covered in, this one or some other thread?

BTW, just consider if this kind of electronic venue would have been available during the hey day of the Apollo program, can you imagine the conversations then???
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/21/2017 06:01 PM
When they attempt a fairing recovery on this mission, which thread would that be covered in, this one or some other thread?

BTW, just consider if this kind of electronic venue would have been available during the hey day of the Apollo program, can you imagine the conversations then???

My presumption is we'll treat this just like landed stages and their missions... The ASDS thread for particulars of the ASDS involved, the return, etc but some coverage here too such as the unload. Just substitute the Fairing Recovery thread for ASDS...

http://forum.nasaspaceflight.com/index.php?topic=37727.0 Fairing Reuse thread
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/21/2017 06:17 PM
I hope you guys are prepared for them to do the exact same thing on another mission.

SpaceX expending end-of-life or obsolete boosters on their final mission has been speculated about extensively here. Usually in the context of customers getting expendable performance for flight-proven prices - but if a customer needs a launch ASAP and an EOL or obsolete booster is the first thing available, I wouldn't be surprised at all to see it happen again.

Edit - spelling is hard.

-Mainly directed at those who seem upset that SpaceX is "wasting" a booster
-Not all comments are based on speculation  ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/21/2017 07:35 PM
When they attempt a fairing recovery on this mission, which thread would that be covered in, this one or some other?
(Snip)
Try
http://forum.nasaspaceflight.com/index.php?topic=37727.0 (http://forum.nasaspaceflight.com/index.php?topic=37727.0)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Flying Beaver on 12/22/2017 12:59 AM
interesting, this may mean nothing, but on the patch s1 has no legs but has fins....

A press kit for this mission is finally available!

And is performing some kind of (four/nine engine?) boostback burn.  :o
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: TGMetsFan98 on 12/22/2017 01:05 AM
On the mission patch, the lucky clover is out in the ocean. I wonder if SpaceX is hoping for some luck with a recovery experiment?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Michael Baylor on 12/22/2017 01:06 AM
https://twitter.com/SandyMazza/status/944024381725982720
That's not very sooty!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Flying Beaver on 12/22/2017 01:12 AM
Is it just me or are those gridfins?

Maybe the patch is accurate and they're trying some entry lifting testing or something along those lines?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/22/2017 01:13 AM
https://twitter.com/SandyMazza/status/944024381725982720
That's not very sooty!

We're probably not seeing the RP-1 tank in that photo

EDIT: I was right, but the RP-1 tank is seen in another photo. There is no soot, except for possibly the interstage. Also a visual confirmation of no legs
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/22/2017 01:14 AM
More to the point - is that a Block 5 interstage or is it just the lighting?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/22/2017 01:15 AM
More to the point - is that a Block 5 interstage or is it just the lighting?

Nope, possibly soot or lighting. Block 5's interstage will be pure black.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: IanThePineapple on 12/22/2017 01:16 AM
Is it just me or are those gridfins?

Maybe the patch is accurate and they're trying some entry lifting testing or something along those lines?

Yeah, looks like grid fins.

I'm guessing they're doing a Cassiope-style water landing with grid fins just to get more data and precision.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Michael Baylor on 12/22/2017 01:18 AM
Is it just me or are those gridfins?

Maybe the patch is accurate and they're trying some entry lifting testing or something along those lines?
It has grid fins.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/22/2017 01:18 AM
Exactly what I'm thinking.... May just be doing a water landing hopefully shill get better pics when its erected

Is it just me or are those gridfins?

Maybe the patch is accurate and they're trying some entry lifting testing or something along those lines?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/22/2017 01:18 AM
More to the point - is that a Block 5 interstage or is it just the lighting?

Nope, possibly soot or lighting. Block 5's interstage will be pure black.
Yeah - just saw the other angle. Guess I’m edgy on this eve of all the new SpaceX letters and numbers! (FH, B5, D2...)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureMartian97 on 12/22/2017 01:18 AM
Why did they clean the stage? Didn't Matt Desch say it wasn't cleaned? Did SpaceX see a lot more drag than they anticipated with CRS-13?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: pb2000 on 12/22/2017 01:51 AM
Why did they clean the stage? Didn't Matt Desch say it wasn't cleaned? Did SpaceX see a lot more drag than they anticipated with CRS-13?
1036 had the entire resource base of Hawthorne, so may have actually been refurbished before 1035, or at the very least had excess intern labour.

I think Elon should charge $100 per square foot for the privilege of washing a F9; at the rate they're recovering them, BFR will be funded in no time flat.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/22/2017 02:03 AM
Another pic from credit user amarkit... Definately grid fins there
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: docmordrid on 12/22/2017 02:29 AM
https://www.youtube.com/watch?v=wtdjCwo6d3Q
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/22/2017 02:43 AM
There really isn't a need to post everything in both the Update and Discussion threads.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: TorenAltair on 12/22/2017 02:44 AM
Would anybody try to land a F9 without legs on a ship structure? (I for sure wouldn't)
How sturdy are those two ships out there?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: gongora on 12/22/2017 02:46 AM
They're not landing on a ship.  The booster is being expended.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: dorkmo on 12/22/2017 04:51 AM
well if you're expending an older version stage, you might as well expend a few old style aluminum grid fins aswell  ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: woods170 on 12/22/2017 06:00 AM
Why did they clean the stage? Didn't Matt Desch say it wasn't cleaned? Did SpaceX see a lot more drag than they anticipated with CRS-13?

No legs on this booster. Leg hold-down hardware was removed from this stage which required cleaning of the lower part of the stage. You than just might as well clean the entire stage.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/22/2017 09:51 AM
Is it just me or are those gridfins?

Maybe the patch is accurate and they're trying some entry lifting testing or something along those lines?

Yeah, looks like grid fins.

I'm guessing they're doing a Cassiope-style water landing with grid fins just to get more data and precision.

Presumably SpaceX would then need to look for and retrieve any significant pieces left floating to avoid being a shipping hazard? Maybe another job for Mr Steven, or is the fairing recovery area likely to be too far form the booster 'landing' position?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: JamesH65 on 12/22/2017 09:59 AM
well if you're expending an older version stage, you might as well expend a few old style aluminum grid fins aswell  ;)

Why?

Even just leaving them off they have scrap value.

I presume they'll be testing something that requires guidance, but likely loss of booster. So just a booster you were going to lose anyway.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: vanoord on 12/22/2017 10:05 AM
Presumably SpaceX would then need to look for and retrieve any significant pieces left floating to avoid being a shipping hazard? Maybe another job for Mr Steven, or is the fairing recovery area likely to be too far form the booster 'landing' position?

It's mostly metal, so it'll sink.

The faster it hits, the more pieces there will be, but even if it soft-lands it'll blow up once it tips over (see previous landing attempts for further information!).

The fairings are composite, so float - and indeed have washed up in various places.

As for locations of where things will land, in theory the fairings would go further, but if they're fitted with steerable parafoils and if the core stage performs any sort of boost after separation, the locations can be altered as required.

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Ben the Space Brit on 12/22/2017 10:19 AM
Grid fins but no legs....

I wonder what they are planning to test that means they are not recovering the booster, but still need guidance.

Are we sure that those are the aluminium ones and not the titanium ones? If it's the latter, they may want to get some data on any difference in performance and guidance authority from the new fins through different atmospheric layers (perhaps due to different responses to heating from different materials) without a drone ship or landing pad in the way to suffer if they've got it wrong.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/22/2017 10:27 AM
No, they are not titanium. And why waist Titanium into the ocean?

Grid fins but no legs....

I wonder what they are planning to test that means they are not recovering the booster, but still need guidance.

Are we sure that those are the aluminium ones and not the titanium ones? If it's the latter, they may want to get some data on any difference in performance and guidance authority from the new fins through different atmospheric layers (perhaps due to different responses to heating from different materials) without a drone ship or landing pad in the way to suffer if they've got it wrong.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: StuffOfInterest on 12/22/2017 11:06 AM
Ok, everyone is hung up on grid fins but no landing legs or the lack of soot. What about the unpainted interstage?  I don't recall seeing that before, but I have missed details a few times.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: nacnud on 12/22/2017 11:20 AM
It looks painted to me, just dirty from its last flight.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ketivab on 12/22/2017 11:31 AM
What are these yellow things on the TEL? They are on 39A, but I am sure they weren't present during previous launches from California.

(https://i.imgur.com/L6vmaXm.jpg)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: KaiFarrimond on 12/22/2017 11:43 AM
What are these yellow things on the TEL? They are on 39A, but I am sure they weren't present during previous launches from California.

(https://i.imgur.com/L6vmaXm.jpg)

They extend and support the payload while Falcon is horizontal. :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: garcianc on 12/22/2017 12:11 PM
Regarding the grid fins, I was wondering if this would be a good mission to test any software changes necessary for the returning stage to fly a side-booster profile trajectory in preparation for the FH mission.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: vanoord on 12/22/2017 12:25 PM
Regarding the grid fins, I was wondering if this would be a good mission to test any software changes necessary for the returning stage to fly a side-booster profile trajectory in preparation for the FH mission.

Yes, but...

The biggest change to the flight back is going to be the requirement to get the boosters apart immediately after separation, ie rather than pointing them directly back they need to fly away from each other - and at that point in the flight the manoeuvring is done using the thrusters (the fins pop out a little later),
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: quagmire on 12/22/2017 12:26 PM
It will be interesting if SpaceX will still cover the 1st stage during its soft landing into the pacific on their stream. I know on their other expendable launches this year, they didn’t, but I believe those lacked grid fins as well and was dropped into the ocean the old fashioned way.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: garcianc on 12/22/2017 12:35 PM
Regarding the grid fins, I was wondering if this would be a good mission to test any software changes necessary for the returning stage to fly a side-booster profile trajectory in preparation for the FH mission.

Yes, but...

The biggest change to the flight back is going to be the requirement to get the boosters apart immediately after separation, ie rather than pointing them directly back they need to fly away from each other - and at that point in the flight the manoeuvring is done using the thrusters (the fins pop out a little later),

Emphasis mine. That's the point. They do not just need to fly away from each other, they need to get back on a track that will bring them back closer again. It will be a somewhat heart-shape mirrored flight pattern and not a parallel formation flight pattern. At no time before has a booster needed to fly in this pattern, so I would expect a software change or, even if the change is a delay maneuver to put both boosters on the same track, at least a test of the flight parameters.

Mods, sorry if this is off-topic. Feel free to move or remove.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: smoliarm on 12/22/2017 12:49 PM
Regarding the grid fins left on expendable booster,
100% speculation:

There were no attempts so far of RTLS landings in VAFB. My guess - the reason is the place is much more dangerous with wildfires than Florida.
Therefore it seems reasonable that VAFB put a requirement - like *N successful demonstrations* of pinpoint accuracy in stage return.
I may be wrong, but it seems to me, that a malfunction resulting in just inaccurate landing - this mishap is much more dangerous in VAFB - it can result if forest fire.

If my guess is right, and there is indeed such a requirement - then this expendable flight still gives an opportunity to demonstrate the required accurate landing (at predefined spot in ocean) and add another *one* towards that *N*.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/22/2017 12:54 PM
Regarding the grid fins, I was wondering if this would be a good mission to test any software changes necessary for the returning stage to fly a side-booster profile trajectory in preparation for the FH mission.
The biggest change to the flight back is going to be the requirement to get the boosters apart immediately after separation, ie rather than pointing them directly back they need to fly away from each other - and at that point in the flight the manoeuvring is done using the thrusters (the fins pop out a little later),

Boosters fly in 3-dimensional space, not 2D.  So, a simple solution is to loft/depress one of the boostback trajectories.  You still aim both directly for the LZs but with non-trivial vertical separation there's basically no chance to collide.

To bring this digression back on topic, [speculation]more likely that they just want to see if they can really find the edge of the envelope with reentry.  They can basically test to destruction because they aren't going to try to recover.  And they don't need the extra performance like they do on expendable flights so they have the margin to afford to add all the mass of the grid fin system.  But there's no need to waste a perfectly good set of legs, so those were left off.  [/speculation]
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/22/2017 01:09 PM
Maybe they are testing how far they can push the angle of attack on return. The more gliding it can do, the less fuel needed for entry and landing burns.

Edit: or maybe they need the fins to make sure they don't hit the fairing recovery boat with flying booster pieces...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: vanoord on 12/22/2017 01:13 PM
To bring this digression back on topic, [speculation]more likely that they just want to see if they can really find the edge of the envelope with reentry.  They can basically test to destruction because they aren't going to try to recover.  And they don't need the extra performance like they do on expendable flights so they have the margin to afford to add all the mass of the grid fin system.  But there's no need to waste a perfectly good set of legs, so those were left off.  [/speculation]

There are probably half a dozen reasons why this is a one-way flight, but it makes every sense to use the remaining propellants to try something different on the way down - whether it's a test for different a trajectory or something like an experiment to see if the vehicle can fly with one grid fin not deployed remains to be seen.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/22/2017 01:16 PM
Perhaps they’re testing a failure mode - such as the loss of one of the fins. In light of the rampant California fires as mentioned above, I would think that proving adequate control authority with such a failure would be a requirement for RTLS.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/22/2017 01:37 PM
1. Maybe they are testing how far they can push the angle of attack on return. The more gliding it can do, the less fuel needed for entry and landing burns.

2. maybe they need the fins to make sure they don't hit the fairing recovery boat with flying booster pieces...

1. That was basically my first thought. 

2. Better to use the engines and boost away from the recovery area.  That would create much more room to ensure safe operations.  Only danger would be a burn failure.  With the grid fins only, something could go wrong after reentry which might cause problems.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: abaddon on 12/22/2017 01:55 PM
I think @envy887 has it right:  with the fairing recovery boat out there they want to control the booster disposal area.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/22/2017 02:05 PM
Edit: or maybe they need the fins to make sure they don't hit the fairing recovery boat with flying booster pieces...

That doesn't make much sense. They can literally move the booster reentry point tens if not hundreds of km away from its ballistic impact point just using a "boostback" burn and for that they only need cold gas thrusters.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: quagmire on 12/22/2017 02:47 PM
Perhaps they’re testing a failure mode - such as the loss of one of the fins. In light of the rampant California fires as mentioned above, I would think that proving adequate control authority with such a failure would be a requirement for RTLS.

Wouldn't they just blow it up in such a case?

Not saying they couldn't test how much control authority they would still have if a fin failed to deploy, but I think such a failure for a RTLS would be an automatic cause for either stopping the maneuvers to get it back to land and let it fall into the ocean or activation of the flight termination system. Don't think VAFB or the Cape would want to take the risk of allowing a booster to return with a failed control system. Drone ship obviously different story.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/22/2017 03:20 PM
Edit: or maybe they need the fins to make sure they don't hit the fairing recovery boat with flying booster pieces...

That doesn't make much sense. They can literally move the booster reentry point tens if not hundreds of km away from its ballistic impact point just using a "boostback" burn and for that they only need cold gas thrusters.

Good point.

Unless they used the recovery margin on ascent, which is unlikely but possible. Though I'm not sure the booster would be controllable if it wasn't able to do a entry burn.

I don't think they have ever had a crew downrange without grid fins on the booster.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/22/2017 03:37 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: alang on 12/22/2017 03:58 PM
The most difficult thing they need to test is the behaviour of a booster shaped like a falcon heavy side booster. Difficult to see how they can do that with a booster with the existing interstage given it has to do the job of stage separation. Cue the Rube Goldberg/Heath Robinson solutions involving discarding the interstage...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/22/2017 04:29 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.

Matt Desch says they are doing a "water landing". Which sounds to me like landing, entry, and maybe even boostback burns are planned, like they are testing something related to EDL (as with the soft water landings on early CRS launches) and the fins aren't just for contingency.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: russianhalo117 on 12/22/2017 04:30 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.

Matt Desch says they are doing a "water landing". Which sounds to me like landing, entry, and maybe even boostback burns are planned, like they are testing something related to EDL (as with the soft water landings on early CRS launches) and the fins aren't just for contingency.
If you read today's NSF article fully it indicates that.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/22/2017 04:42 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.

Matt Desch says they are doing a "water landing". Which sounds to me like landing, entry, and maybe even boostback burns are planned, like they are testing something related to EDL (as with the soft water landings on early CRS launches) and the fins aren't just for contingency.

I was indicating that since it's possible they'll skip the boostback burn judging by the 1st stage burn length, my earlier statement that they would be able to significantly redirect the stage away from fairing recovery area loses some credence.

However, my favorite theory is still that the fins are there to explore the limits of lifting entry as all other flights had guidance targets so they might not have explored the entire parameter space.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: envy887 on 12/22/2017 04:54 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.

Matt Desch says they are doing a "water landing". Which sounds to me like landing, entry, and maybe even boostback burns are planned, like they are testing something related to EDL (as with the soft water landings on early CRS launches) and the fins aren't just for contingency.
If you read today's NSF article fully it indicates that.

But unlike Desch's tweet, the article doesn't imply it's sourced directly from SpaceX.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: russianhalo117 on 12/22/2017 05:36 PM
Unless they used the recovery margin on ascent, which is unlikely but possible.

I guess that's a possibility. The press kit for this mission has MECO several seconds later than on earlier Iridium flights and it's closer to, say, Koreasat-5A launch which did not employ a boostback burn.

Matt Desch says they are doing a "water landing". Which sounds to me like landing, entry, and maybe even boostback burns are planned, like they are testing something related to EDL (as with the soft water landings on early CRS launches) and the fins aren't just for contingency.
If you read today's NSF article fully it indicates that.

But unlike Desch's tweet, the article doesn't imply it's sourced directly from SpaceX.
Article info generally comes out of L2 and from SpaceX sources.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: WheelsStop on 12/22/2017 06:11 PM
From the update thread (https://forum.nasaspaceflight.com/index.php?topic=44273.msg1762722#msg1762722) there's something different with airspace restrictions this time around.  There's a flight restriction up as an eastern extension of W-537.  Is this launch taking a more easterly track than the other Iridium launches?

I think it's too close in-shore, but given the other discussion here, I'm tempted to speculate that they're going to drop the first stage in that vicinity and want a little extra space.  Perhaps as a lead up to an RTLS?  Again, total speculation.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Brunberg on 12/22/2017 06:32 PM
I think the boosters are recovered from the ocean no matter what.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: joek on 12/22/2017 06:51 PM
From the update thread (https://forum.nasaspaceflight.com/index.php?topic=44273.msg1762722#msg1762722) there's something different with airspace restrictions this time around.  There's a flight restriction up as an eastern extension of W-537.  Is this launch taking a more easterly track than the other Iridium launches?

Maybe a bit.  Most recent launch license LLS 17-096B (Rev 2) (https://www.faa.gov/about/office_org/headquarters_offices/ast/licenses_permits/media/LLS%2017-096B%20Rev%202.pdf) update (sec. 2 pg. 2):
Quote
Revision 2 - Issued October 6, 2017
1. Paragraph (3)(c) changed from "On a flight azimuth .of 179.2 degrees" to "On a flight azimuth between 175 and 180 degrees".
Or could be the current publicly accessible license is not up to date (would not be unusual).
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ChrisGebhardt on 12/22/2017 06:54 PM
Regarding the grid fins left on expendable booster,
100% speculation:

There were no attempts so far of RTLS landings in VAFB. My guess - the reason is the place is much more dangerous with wildfires than Florida.
Therefore it seems reasonable that VAFB put a requirement - like *N successful demonstrations* of pinpoint accuracy in stage return.
I may be wrong, but it seems to me, that a malfunction resulting in just inaccurate landing - this mishap is much more dangerous in VAFB - it can result if forest fire.

If my guess is right, and there is indeed such a requirement - then this expendable flight still gives an opportunity to demonstrate the required accurate landing (at predefined spot in ocean) and add another *one* towards that *N*.

There's a lot of assumption here.

1. Wildfires have nothing to do with Falcon 9 landings. Florida is extremely prone to fires in winter and spring outside the state's rainy season.  There's no correlation as you're implying.
2. If Vandenberg officials were that concerned over the potential of a rocket to start a fire they wouldn't be able to handle, they would:
     a. not have approved SpaceX building the landing pad
     b. not let anyone launch from Vandenberg because of the risk of failure and associated fire risk to a failing rocket (whether launching or landing)
     c. not let SpaceX static fire (which has started at least one fire just this year)
3. Assuming your point, however, how are the 20 successful, pin-point landings to date not enough to prove the system?
4. Vandenberg is not the licensing authority for landings.  They don't get that much of a say over "now you have to do x number of things before we're happy."
5. There is no difference - from the Falcon 9's landing systems - to an RTLS landing at CCAFS v. Vandenberg.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: philw1776 on 12/22/2017 06:55 PM
I think the boosters are recovered from the ocean no matter what.

I doubt that as no reports of large ship with crane ship activity near impact points.
No NSF guys reporting ship coming back with large shrouded object, etc.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Herb Schaltegger on 12/22/2017 06:59 PM
I think the boosters are recovered from the ocean no matter what.

I doubt that as no reports of large ship with crane ship activity near impact points.
No NSF guys reporting ship coming back with large shrouded object, etc.
Further, we’ve seen videos of what happens to a first stage once it tumbles over. Not a lot left typically but fragments. ;)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: whatever11235 on 12/23/2017 12:31 AM
Was that boostback burn after stage separation?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: HVM on 12/23/2017 12:35 AM
yes.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/23/2017 12:39 AM
no word on fairing but they never say. Much less public info about fairings than about the S1 landings when those were under development...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ngilmore on 12/23/2017 12:44 AM
View of launch from Los Angeles.

If I'd known it was going to be this spectacular, I would have had a better camera ready.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jimmiemac on 12/23/2017 12:46 AM
View from San Diego.  Apologies for the poor quality.  Taken with my cell phone.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Kenp51d on 12/23/2017 12:52 AM
Great shots. Looks like your timing was  dead on.  Caught stage separation.


Ken

Sent from my V10 using Tapatalk

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RocketLover0119 on 12/23/2017 12:52 AM
Can somebody tell the people on reddit los Angeles to take a chill pill -.-
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/23/2017 12:55 AM
Can somebody tell the people on reddit los Angeles to take a chill pill -.-

lol.  The mods there stickied a post explaining and there are still a dozen "WTF is that?" posts.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: xyv on 12/23/2017 12:55 AM
Watched it from the Santa Barbara area.  Looked to me like the first stage kept burning for a long time after separation - doing extreme maneuvers for quite awhile.  Now I am thinking that it was the cold thrusters making large swirls that were visible in the sunlight.  Really a wild show.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jim6398 on 12/23/2017 12:56 AM
Pics from Santa Barbara
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Michael Baylor on 12/23/2017 12:58 AM
No offense but this is an update thread....

Best launch that I have ever seen. Absolutely incredible. OMG!!! An RTLS in Florida is no where close. Launch was sensational. Then the sun lit up the plume. WOW. But it was just getting started. Stage sep and boostback had the usual amazing effects at night. However, the sun lit up the fairings. I could see both for over two minutes. One all the way through reentry. Eventually the hills blocked it. Then there was the first stage. The sun lit it up against a black backdrop. I saw that the whole way until the hill got in the way. Nitrogen thrusters visible, but the entry burn from a couple hundred miles away was the highlight of the night. WOW WOW WOW!! Never expected to see that today. Speechless. One of the best experiences of my life.

Words cannot do this justice.
Visual confirmation of fairing reentry is an update. Your post was anything but.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/23/2017 01:00 AM
Video clips taken in LA

https://www.reddit.com/r/LosAngeles/comments/7llt4c/what_is_this_flying_above_la_right_now/

https://www.reddit.com/r/LosAngeles/comments/7llwnc/video_of_rocket_over_venice/ 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: SciNews on 12/23/2017 01:10 AM
Replay of the SpaceX Falcon 9 Iridium-4 launch
https://www.youtube.com/watch?v=-lZvUjKhvBw
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: e of pi on 12/23/2017 01:22 AM
Those short "burp" restarts always freak me out. Merlin never reaches the glowing steady state that's my indicator of health for it, and it barely gets done jittering with start before it's jittering with shutdown...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 12/23/2017 01:24 AM
Holy cow...

https://www.youtube.com/watch?v=tE5C3O71Xqo&ab_channel=DougEllison


(PS: Not my vid)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Helodriver on 12/23/2017 01:27 AM
The most visually impressive launch from my Vandenberg back yard in years and I'm driving across Louisiana 2000 miles away. Yay for lousy holiday timing. ;) Love that twilight effect high altitude light.  Nice job those who captured it. :)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: xyv on 12/23/2017 01:37 AM
Looking at the Alhambra video I can see it was cold thrusters.  From my view there was a whole bunch more action from the first stage.  we could also clearly see both fairings separate and fall.  The sunlight versus dark was near perfect for the most spectacular launch I've seen 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: fwskungen on 12/23/2017 01:42 AM
Hello Can someone tell me what that white crystal thingy is? id asume its frozen oxygen or RP1? but im just gessing
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Perchlorate on 12/23/2017 01:42 AM
Okay, SpaceX, great job.  Now let us see the splashdown video!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RedSky on 12/23/2017 01:43 AM
Good close up.  Starting around 1:50, is one of the fairings thrusting?

https://www.youtube.com/watch?v=ioG7PaQkDog
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Eagandale4114 on 12/23/2017 01:49 AM
Hello Can someone tell me what that white crystal thingy is? id asume its frozen oxygen or RP1? but im just gessing
That’s a hunk of frozen oxygen.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: TripD on 12/23/2017 01:52 AM
Hello Can someone tell me what that white crystal thingy is? id asume its frozen oxygen or RP1? but im just gessing

Yes.  John Insprucker explained it during the webcast.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AncientU on 12/23/2017 01:57 AM
50 years.

Welcome to space age v2.0
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Wolfram66 on 12/23/2017 02:01 AM
https://www.youtube.com/watch?v=iyKAJsQngIc (https://www.youtube.com/watch?v=iyKAJsQngIc) from Jim Mudgett on YouTube
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: freda on 12/23/2017 02:01 AM
Visiting Palm Springs CA. Watched the Iridium launch on YouTube stream from hotel bar. Few minutes later, spouse said “what’s that light in the sky”. I immediately jumped over the table and dashed outside and had a nice view of S2 pushing south. A very unexpected bonus to a Christmas vacation!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Marine_Mustang on 12/23/2017 02:12 AM
From Oceanside, CA.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: mdeep on 12/23/2017 02:27 AM
Is this the first launch that featured both a liftoff from darkness into sunlight at altitude and a stage return? I've been waiting to see one of these in this lighting, and I think the last SpaceX launch that had this timing predated stage recovery.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: catdlr on 12/23/2017 03:18 AM
Launch in 4K

SpaceX Iridium 4 Launch from Alhambra, CA

Doug Ellison
Published on Dec 22, 2017

DJI Mavic Pro from Alhambra, CA

https://www.youtube.com/watch?v=tE5C3O71Xqo?t=001

https://www.youtube.com/watch?v=tE5C3O71Xqo
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: xyv on 12/23/2017 03:22 AM
The video from Mudgett to really shows it.  The first stage shows wild swirls that are caused by the periodic fireing of the cold thrusters.  Later you see the fairings drop off.  The whole time the first stage is as bright as the still firing second stage.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jimbowman on 12/23/2017 03:26 AM
from Jim Mudgett on YouTube

First stage blowing some serious smoke rings
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cppetrie on 12/23/2017 03:42 AM
SpaceX Falcon 9 Launch, Boostback, Landing Burn - Iridium-4 - 2017-12-22


Justin Foley
Published on Dec 22, 2017

The launch of SpaceX Falcon 9 rocket from Vandenberg Air Force Base on December 22th, 2017. It carried 10 Iridium satellites. INCREDIBLE!! You can see the 1st stage shut down, stage separation, 2nd stage engine start, THE FAIRINGS! and their RCS thrusters, the first stage boost back burn started, AND the first stage landing burn!!


https://www.youtube.com/watch?v=UU5KpfOT-_Y?t=001

https://www.youtube.com/watch?v=UU5KpfOT-_Y
A couple of things struck me watching this video:
1) RCS thruster bursts are readily visible from the booster and one of the fairings. The other fairing I don’t think ever displayed any RCS bursts. My conclusion is that only one of the fairings was loaded with recovery hardware.
2) the fairing demonstrating the RCS bursts appears to fall much slower than the one that does not suggesting a slowed descent from chutes. It could just be perspective that creates that illusion, though.
3) the landing burn of the booster is clearly visible and quite bright against the dark sky. It is visible to within a fairly low altitude and the camera stays low for several seconds afterwards. There is no flash visible at any point after the booster goes below the horizon, which I would have expected a dim flash had the booster exploded after falling in the drink. The lack of a flash leads me to think that the booster remained in one piece.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Req on 12/23/2017 04:07 AM

3) the landing burn of the booster is clearly visible and quite bright against the dark sky. It is visible to within a fairly low altitude and the camera stays low for several seconds afterwards. There is no flash visible at any point after the booster goes below the horizon, which I would have expected a dim flash had the booster exploded after falling in the drink. The lack of a flash leads me to think that the booster remained in one piece.

Entry burn.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Marine_Mustang on 12/23/2017 04:55 AM
This is interesting; a different perspective (from Tehachapi, to the north) as well as a time-lapse.

https://twitter.com/RogerCraigSmith/status/944393685571067904 (https://twitter.com/RogerCraigSmith/status/944393685571067904)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: wannamoonbase on 12/23/2017 05:42 AM
Congrats SpaceX and Iridium.

Massive year for both.

SpaceX with 18 successful missions and 5 reflown cores.

What an age we live in.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jebbo on 12/23/2017 05:59 AM
Oh dear, Demi Lovato thinks it's a conspiracy:

Quote
I’m calling Incorrect on SpaceX’s excuse. That shit’s a UFO and there’s been others that have been seen that are just like it!!
https://twitter.com/ddlovato/status/944408972496216064 (https://twitter.com/ddlovato/status/944408972496216064)

[ Not sure if this really belongs here or in the party thread. Please move if necessary ]

--- Tony
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/23/2017 08:27 AM
So they did perform a boostback burn in the end after all, but an obviously shorter one and on a single engine only.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Stan Black on 12/23/2017 08:38 AM
In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/23/2017 09:22 AM
If you look at the archived webcast at around 17:20 in, the IR camera nicely shows how virtually the entire rocket is being engulfed in recirculating exhaust near the end of 1st stage burn, being responsible for at least part of the soot buildup on the returning boosters.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Star One on 12/23/2017 11:06 AM
Oh dear, Demi Lovato thinks it's a conspiracy:

Quote
I’m calling Incorrect on SpaceX’s excuse. That shit’s a UFO and there’s been others that have been seen that are just like it!!
https://twitter.com/ddlovato/status/944408972496216064 (https://twitter.com/ddlovato/status/944408972496216064)

[ Not sure if this really belongs here or in the party thread. Please move if necessary ]

--- Tony

She’s not the only one look at some of the quotes in this article.

http://www.ibtimes.co.uk/mysterious-ufo-glowing-tail-hovering-over-los-angeles-stuns-onlookers-aliens-are-landing-1652643
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ugordan on 12/23/2017 11:11 AM
One more airborne video, just for the commentary's sake.

https://www.youtube.com/watch?v=QHYx-ueq0Kg
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: su27k on 12/23/2017 11:29 AM
Telephoto video taken by a SpaceX employee, some nice outreach: https://www.youtube.com/watch?v=nqr4rMVSpYo
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: nacnud on 12/23/2017 11:35 AM
Hey considering he had no idea what it was to start with he worked it out fairly quickly, had me  ;D ;D ;D at the beginning!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: nisse on 12/23/2017 01:07 PM
Did SpaceX perform some experimental landing manoeuvre since they didn't want to risk the drone ship? Maybe some high speed energy saving scheme?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: clongton on 12/23/2017 01:07 PM
What was the purpose of a boostback and entry burn for a vehicle that was intended to be disposed of?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: ZachS09 on 12/23/2017 01:08 PM
What was the purpose of a boostback and entry burn for a vehicle that was intended to be disposed of?

Just to simulate a first stage landing profile. Might as well do more testing.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Herb Schaltegger on 12/23/2017 01:10 PM
Did SpaceX perform some experimental landing manoeuvre since they didn't want to risk the drone ship? Maybe some high speed energy saving scheme?

Read L2 if you have it. If you don't have it, it's worth it. Disposing of the core wasn't about "not risking" the drone ship; after all, this very core was landed on the drone ship some months back, wasn't it?

What was the purpose of a boostback and entry burn for a vehicle that was intended to be disposed of?

SpaceX was either: #1) testing flight parameters of the entering/landing stage; #2) ensuring that the stage didn't interfere with fairing recovery attempts by guiding it as if it were a standard entry/landing; #3) just performing an exercise for control personnel and software procedures - "Test as you fly!" and all that; or #4) some combination of the above factors.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Kaputnik on 12/23/2017 01:15 PM
In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.

OTOH think of all the diesel they saved by not steaming out there with an ASDS...
But yeah I kind of agree with you. Single-use launch vehicles are starting to look like how we used to do this...
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: LouScheffer on 12/23/2017 02:16 PM
One more airborne video, just for the commentary's sake.

https://www.youtube.com/watch?v=QHYx-ueq0Kg
This guy did a great job of reporting, in my view.   He did not jump to conclusions (What is that?  I've never seen anything like it?), then he worked out it was likely a rocket launch, then why it looked the way it did (launched in the dark, rose into the sun).   He stated what he was sure of (North to South) and what he could not tell (east to west or west to east).   Excellent real-time reporting of an unusual event.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: aero on 12/23/2017 02:18 PM
How far away from Vandenburg was the farthest confirmed viewing of the launch. We saw it very clearly here in San Diego, it was spectacular. But San Diego is not that far from the ground track, there is video from Phoenix. Anything farther away?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: sevenperforce on 12/23/2017 02:21 PM
In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.

OTOH think of all the diesel they saved by not steaming out there with an ASDS...
But yeah I kind of agree with you. Single-use launch vehicles are starting to look like how we used to do this...
In a strange way, the idea of dumping a reused booster actually validates the economics of reuse.

Recalling the days when people said "They'll never be able to recover them" which quickly turned into "They can recover them, but they won't be able to refly them." Now, they're so successful at recovery that they can actually make a business decision about expending a booster after one reflight.

Those kinds of economic profit-and-loss decisions are what you'd expect if reuse was actually about profitability and not just one charismatic rich guy's obsession.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: RDoc on 12/23/2017 02:45 PM
There appeared to be things separating from what I assume to be the returning booster, does anyone have any thoughts on what they are?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/23/2017 02:46 PM
How far away from Vandenburg was the farthest confirmed viewing of the launch. We saw it very clearly here in San Diego, it was spectacular. But San Diego is not that far from the ground track, there is video from Phoenix. Anything farther away?

South Africa! 

https://www.youtube.com/watch?v=2qquAXBpcA4
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: deruch on 12/23/2017 02:48 PM
There appeared to be things separating from what I assume to be the returning booster, does anyone have any thoughts on what they are?

Thruster firings.  So, plumes of cold nitrogen gas.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: king1999 on 12/23/2017 02:54 PM
There appeared to be things separating from what I assume to be the returning booster, does anyone have any thoughts on what they are?

Thruster firings.  So, plumes of cold nitrogen gas.
The angry fume from S1 when it realized that no droneship was awaiting. ;D
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/23/2017 03:03 PM


2) the fairing demonstrating the RCS bursts appears to fall much slower than the one that does not suggesting a slowed descent from chutes. It could just be perspective that creates that illusion, though.

I think you're right about slower descent, although you're right it could be greater/less distance from the viewer or other trick of perspective.  I don't think it's a parachute responsible at that altitude, though; I'm pretty sure the different profile is solely to due the fact that the active half is actively attitude-controlled.  Instead of tumbling and diving nose first like the passive half, the active half is in a controlled glide, round side down, like a flying bathtub.  That accounts for its greater altitude, or greater horizontal distance (if it's a perspective effect)---or both.

Parachute deployment would wait until the fairing is back in the sensible atmosphere, and maybe later, depending on the tradeoffs between cold gas control authority and parafoil control authority.  The parafoil needs at least enough atmosphere present to deploy properly, even if the first deployment is just a hypersonic drogue.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: SLC on 12/23/2017 03:06 PM
As for what the first-stage water-landing experiment might have been ... 

Looking ahead to the landing-back-on-your-launch-mounts thing, could it have been some kind of simulation of landing an F9 back on its mounts?  Or at least positioning it with centimetre accuracy relative to some specified target, rather than the metre accuracy now routine with the ASDS?

I know there are no plans to physically land an F9 back on its hold-down clamps, but this kind of simulation might validate some of the BFR control routines, and retire at least some of the risk before they have to do it for real with the prototype BFR.  They traded landing legs for extra landing fuel, and that might have allowed some precision sideways positioning.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cscott on 12/23/2017 03:16 PM
I strongly suspect the first cradle landing experiments will take place on land, in the middle of a big empty field. (LZ-1 at the Cape might count; as would McGregor.)

It's hard to measure sub-meter positioning in the middle of a moving ocean.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Johnnyhinbos on 12/23/2017 03:30 PM
it's a moot point regardless - as SpaceX has specifically said that without bottom mounted RCS they don't have enough control authority for that level of precision. I wouldn't anticipate that they will put any development into cradle landing on the Falcon family. They are already gearing up for the BFR family development and will engineer in that type of fine control from the outset.

 
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: SLC on 12/23/2017 06:09 PM
<snip>
It's hard to measure sub-meter positioning in the middle of a moving ocean.
I was thinking more of relative movement; sort of "slide 5 m North - now 4 m East - now 3 m South - now 2 m West and ... fall into the sea".  Like rocket dressage.  I think acceleration sensors might be able to track the rocket's responses to the centimetre.

I also take the point about bottom-mounted RCS.  But I thought they might want to explore the outer limits of control authority possible with just nozzle-gimballing and top-mounted RCS (with hardware that's just experienced a re-entry).  At least this would tell them how forceful the bottom-mounted BFR RCS will need to be.

Of course they've modelled all this already.  But data points are always reassuring.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Eagandale4114 on 12/23/2017 07:34 PM
How far away from Vandenburg was the farthest confirmed viewing of the launch. We saw it very clearly here in San Diego, it was spectacular. But San Diego is not that far from the ground track, there is video from Phoenix. Anything farther away?

Some guys in Tucson were able to see it! There were some pictures on reddit. I forget the user but they posted this.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Lar on 12/23/2017 09:05 PM
it's a moot point regardless - as SpaceX has specifically said that without bottom mounted RCS they don't have enough control authority for that level of precision. I wouldn't anticipate that they will put any development into cradle landing on the Falcon family. They are already gearing up for the BFR family development and will engineer in that type of fine control from the outset.

 

I think it is possible to take a flown stage and make it into a mule, including adding bottom mounted RCS, to do these kinds of tests. However I don't think it's necessarily cost effective. I also don't think we'd ever see it on a customer flight.

...I expect the first mules will be Raptor engined. Which means off topic for here.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: dcporter on 12/23/2017 09:43 PM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 12/23/2017 10:02 PM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Yeknom-Ecaps on 12/23/2017 10:13 PM
Was there a payload fairing recovery attempt? If so, any results?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 12/23/2017 10:26 PM
Was there a payload fairing recovery attempt? If so, any results?

Probably since Mr Steven moved in the area, but it seems we'll have to wait for her to return to see whether they've succeeded or not.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: speedevil on 12/24/2017 03:40 AM
I think it is possible to take a flown stage and make it into a mule, including adding bottom mounted RCS, to do these kinds of tests. However I don't think it's necessarily cost effective. I also don't think we'd ever see it on a customer flight.

...I expect the first mules will be Raptor engined. Which means off topic for here.

They have said it doesn't have enough control authority, which presumably is true for the assumptions made, and no on-vehicle mods.

Several things might in principle be done to make those assumptions not hold with limited investment.
A) Much, much better wind prediction for landing winds.
    Taking the mispredicted worst case error from winds from 10m/s over the last 4 seconds to 0.5m/s. Feeding a local instantaneous wind model from high power LASER based doppler radar for studying wind flow out to ~200m, a swarm of drones at 200m radius, or even something as simple as a field of anemometers.
B) Non-fixed cradle
   This might vary from at the high end something able to dynamically control orientation and position of the cradle to catch and slow the caught stage to rest. Or, rather more simply, to accelerate at Tesla truck type speeds, tracking the predicted optimal impact point, then clamp to the deck after braking rapidly.

B) is clearly (probably) useless for a BFR with properly sized control thrusters.

However, A) might be moderately useful for BFR, and perhaps even more useful in the near-term for fairing recovery.
Might even be useful for the rather sillier idea of catching S2 in a net.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: dcporter on 12/24/2017 05:12 AM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.

Yes right sorry, I was asking why there was no booster recovery, not why there was no thread.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hkultala on 12/24/2017 05:52 AM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.

So, who is the first to recover some parts of it with a submarine?

The chinese, to py on spacx tech?

Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: FutureSpaceTourist on 12/24/2017 06:03 AM
Quote
I think last night might have been the biggest Rorschach test ever

https://twitter.com/elonmusk/status/944700127100497920

Quote
Having a sinking feeling that most people actually do think it was aliens …

https://twitter.com/elonmusk/status/944779560104574977

Quote
So strange that people often believe things inversely proportionate to the evidence. Given a set of possible explanations, why pick the extremely unlikely one!?

https://twitter.com/elonmusk/status/944787213430034432
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 12/24/2017 10:51 AM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.

Yes right sorry, I was asking why there was no booster recovery, not why there was no thread.

Seems like Block 3s are starting to be phased out in favor of Block 4 and soon Block5 cores.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: tvg98 on 12/24/2017 10:54 AM
https://www.youtube.com/watch?v=Ff7wbSwTuEk

So I was wondering whether there were accidents caused by people being distracted with the launch, and sure enough it happened.

PS: Some strong language's present
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: cambrianera on 12/24/2017 12:03 PM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.

Yes right sorry, I was asking why there was no booster recovery, not why there was no thread.

Maybe they had no set of legs available.
Three sets are matched to the FH boosters, one set is on Zuma.
The legs are ligth, but not cheap.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Herb Schaltegger on 12/24/2017 12:41 PM
Apologies, morning confident that this has been discussed but it will have been back ?? pages: what happened to booster recovery this mission?

This booster was not recovered, hence no booster recovery thread.

Yes right sorry, I was asking why there was no booster recovery, not why there was no thread.

Maybe they had no set of legs available.
Three sets are matched to the FH boosters, one set is on Zuma.
The legs are ligth, but not cheap.
This booster was previously-recovered. There's not a shortage of legs.

And there's some insight on L2 about why the booster wasn't recovered and lack of legs wasn't the reason.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Skylab on 12/24/2017 12:52 PM
Mr. Steven, reportedly charged with capturing a fairing has been in port for some time now. Hope we get to see some results soon!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Oersted on 12/24/2017 02:04 PM
https://www.youtube.com/watch?v=Ff7wbSwTuEk

So I was wondering whether there were accidents caused by people being distracted with the launch, and sure enough it happened.

PS: Some strong language's present

The US is finally catching up to Russia when it comes to dashcam excitement!
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Nomadd on 12/24/2017 02:11 PM
https://www.youtube.com/watch?v=Ff7wbSwTuEk

So I was wondering whether there were accidents caused by people being distracted with the launch, and sure enough it happened.

PS: Some strong language's present

The US is finally catching up to Russia when it comes to dashcam excitement!
It kind of looks like we're returning fire for Chelyabinsk.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Stan Black on 12/24/2017 02:30 PM
In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.

OTOH think of all the diesel they saved by not steaming out there with an ASDS...
But yeah I kind of agree with you. Single-use launch vehicles are starting to look like how we used to do this...
In a strange way, the idea of dumping a reused booster actually validates the economics of reuse.

Recalling the days when people said "They'll never be able to recover them" which quickly turned into "They can recover them, but they won't be able to refly them." Now, they're so successful at recovery that they can actually make a business decision about expending a booster after one reflight.

Those kinds of economic profit-and-loss decisions are what you'd expect if reuse was actually about profitability and not just one charismatic rich guy's obsession.

Should the rocket be dumped in the sea or recovered then scrapped?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: sevenperforce on 12/24/2017 02:53 PM
In a strange way, the idea of dumping a reused booster actually validates the economics of reuse.

Recalling the days when people said "They'll never be able to recover them" which quickly turned into "They can recover them, but they won't be able to refly them." Now, they're so successful at recovery that they can actually make a business decision about expending a booster after one reflight.

Those kinds of economic profit-and-loss decisions are what you'd expect if reuse was actually about profitability and not just one charismatic rich guy's obsession.

Should the rocket be dumped in the sea or recovered then scrapped?
Exactly.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: hootowls on 12/24/2017 11:50 PM
In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.

OTOH think of all the diesel they saved by not steaming out there with an ASDS...
But yeah I kind of agree with you. Single-use launch vehicles are starting to look like how we used to do this...
In a strange way, the idea of dumping a reused booster actually validates the economics of reuse.

Recalling the days when people said "They'll never be able to recover them" which quickly turned into "They can recover them, but they won't be able to refly them." Now, they're so successful at recovery that they can actually make a business decision about expending a booster after one reflight.

Those kinds of economic profit-and-loss decisions are what you'd expect if reuse was actually about profitability and not just one charismatic rich guy's obsession.

Should the rocket be dumped in the sea or recovered then scrapped?

(Non reflight booster) Dumped unless someone pays for recovery. ASDS deployment itself (excluding the rest of the booster handling) is not inexpensive. And there’s the risk of damage to the ASDS that might impact the schedule of a needed recovery.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: TorenAltair on 12/25/2017 12:35 AM
Imho, not everything is about money or costs but of changing attitude in general to the Earth system (ecosphere, biosphere, hydrosphere, atmosphere etc.). We're basically killing only ourselves, Earth will harbor life long time after we'll be vanished. Just my opinion.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: HVM on 12/25/2017 07:20 AM
And Scott get, -yet again, basic stuff wrong, not even put timing of the staging right. Also irregular part of the second stage's plume is due the first stage's short boostback burn. Blah.

Ah, sorry I'm just grumpy, and both of the TMRO and Scott's Tube annoy me for some reason. I should like all space related stuff in YouTube (there not so many space related channel in there) but no.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: catdlr on 12/25/2017 07:25 AM
And Scott get, -yet again, basic stuff wrong, not even put timing of the staging right. Also irregular part of the second stage's plume is due the first stage's short boostback burn. Blah.

Sorry, that will be my last post from him.  Thanks for the critique HMV.  Post deleted.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: HVM on 12/25/2017 08:19 AM
So now that feel guilty, here is Scott Manley's vid.
https://www.youtube.com/watch?v=CJ6nn8fZOmc (https://www.youtube.com/watch?v=CJ6nn8fZOmc)

Everyday Astronaut's
https://www.youtube.com/watch?v=EGOaHm0s6Es (https://www.youtube.com/watch?v=EGOaHm0s6Es)
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Llian Rhydderch on 12/28/2017 11:52 AM
I don't think the "Should ..." question is really for us. 

Normative questions like that are best left for the private entity that made the thing, owns the thing, and can consider all of the costs associated with the recover/DontRecover decision.

SpaceX made the decision, for quite likely a complex set of many things that made up their rationale, including that it was apparently a block 3 booster, ...

They own the rocket, and incur the costs of recovery.  They get to decide. 

In this age of recycle and environment considerations, and Blue Planet II, I find dumping a rocket that can be recovered leaving me conflicted.

OTOH think of all the diesel they saved by not steaming out there with an ASDS...
But yeah I kind of agree with you. Single-use launch vehicles are starting to look like how we used to do this...
In a strange way, the idea of dumping a reused booster actually validates the economics of reuse.

Recalling the days when people said "They'll never be able to recover them" which quickly turned into "They can recover them, but they won't be able to refly them." Now, they're so successful at recovery that they can actually make a business decision about expending a booster after one reflight.

Those kinds of economic profit-and-loss decisions are what you'd expect if reuse was actually about profitability and not just one charismatic rich guy's obsession.

Should the rocket be dumped in the sea or recovered then scrapped?
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: AncientU on 12/30/2017 04:31 PM
This is incredible:
http://www.mirror.co.uk/news/world-news/remarkable-time-lapse-video-more-11772088
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: jpo234 on 12/30/2017 07:41 PM
This is incredible:
http://www.mirror.co.uk/news/world-news/remarkable-time-lapse-video-more-11772088
https://www.youtube.com/watch?v=kOw3P6aKDgA
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Comga on 12/31/2017 02:02 PM
https://www.nasaspaceflight.com/2017/11/iridium-next-4-december-launch-vandenberg/ (https://www.nasaspaceflight.com/2017/11/iridium-next-4-december-launch-vandenberg/)
Quote
Iridium NEXT-4 is scheduled to launch from SLC-4E on Vandenberg Air Force Base No Earlier Than (NET) 22 December 2017 at an instantaneous launch time of 17:32 PST (01:32 UTC on 23 December).

So SpaceX held that NET launch date for most of a month at least.
An improvement from their general track record
A fourth flight of its type on a "flight proven" booster
This bodes well for working through their backlog.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: kdhilliard on 12/31/2017 02:50 PM
...
So SpaceX held that NET launch date for most of a month at least.
...

Try "for over two months"!
And the presser is out:
...

MCLEAN, Va. – October 19, 2017 - Iridium Communications Inc. (NASDAQ: IRDM) announced today that the fourth Iridium NEXT launch has been targeted by SpaceX for December 22, 2017 at 5:26 p.m. PT [1:26 a.m. UTC on Dec. 23], from Vandenberg Air Force Base.  ...

...
This bodes well for working through their backlog.

Yes indeed!  Though, as much as SpaceX has accomplished in the last year, 3 September 3016 wasn't so long ago.  I share the thoughts of those folks in the FH thread expecting to hold their breath until those boosters are well clear of 39A, but truth be told, my face turns blue just about every launch.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Kaputnik on 01/01/2018 08:00 AM
This is incredible:
http://www.mirror.co.uk/news/world-news/remarkable-time-lapse-video-more-11772088

I love how the media report on space stuff. This article says that the Falcon 9 'aircraft' will soon require less refurbishment between flights- without mentioning that the mere idea of reflying a rocket was still unknown less than a year ago.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Norm38 on 01/07/2018 04:21 PM
Haven't seen this one posted yet. The LA skyline in the distance gives a nice sense of scale.
https://www.youtube.com/watch?v=c4Xpu-jN6gw
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: Machdiamond on 01/07/2018 07:37 PM
This was posted in the update thread, see "drone footage" in reply #270 with a link to the original video from Doug Ellison.

It wasn't imbedded so it was easy to miss though.

Definitely one of the best.
Title: Re: SpaceX Falcon 9 : Iridium NEXT Flight 4 : December 22/23, 2017 : Discussion
Post by: catdlr on 01/07/2018 11:40 PM
This was posted in the update thread, see "drone footage" in reply #270 with a link to the original video from Doug Ellison.

It wasn't imbedded so it was easy to miss though.

Definitely one of the best.

and the original by Doug is in 4K.