NASASpaceFlight.com Forum

Commercial and US Government Launch Vehicles => NGIS (Formerly Orbital ATK) - Antares/Cygnus Section => Topic started by: Chris Bergin on 04/17/2013 02:56 AM

Title: Antares A-One General Discussion Thread (2)
Post by: Chris Bergin on 04/17/2013 02:56 AM
DISCUSSION THREAD FOR ANTARES A-ONE MISSION - From launch day to post launch.

Please note the difference between this thread and the update thread.

UPDATE THREAD IS HERE:
http://forum.nasaspaceflight.com/index.php?topic=31663.0

For everything else, here's the Party Thread:
http://forum.nasaspaceflight.com/index.php?topic=30923.0

Viewing Opportunities/Going to the Launch:
http://forum.nasaspaceflight.com/index.php?topic=31517.0

Resources:

Orbital GENERAL Forum Section:
http://forum.nasaspaceflight.com/index.php?board=46.0

Orbital (Antares/Cygnus) News Articles (Recent):
http://www.nasaspaceflight.com/tag/antares/

L2 Antares/Cygnus Section:
http://forum.nasaspaceflight.com/index.php?action=tags&tags=orbital
(Includes updates, videos, graphics, presentations and specific interactive posts with engineers etc.).


As always, stay on topic and use the correct threads.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: spacedog71 on 04/17/2013 03:38 AM
hello chris,

are the official odds for tomorrow still 30%, or was the stated 45% later this afternoon (that i now can't even find) the new official word?

...and given that i'm about four hours away, do you think there will be another recalculation before noon tomorrow? ::)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Chris Bergin on 04/17/2013 03:42 AM
Now that would be a really good post in the new discussion thread....so let's move that there.

I believe the 30 percent was factoring in the potential for a scrub due to vehicle/GSE issue.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: spacedog71 on 04/17/2013 04:44 AM
found it.

http://www.nasa.gov/exploration/commercial/cargo/orbitalsciences-index.html (http://www.nasa.gov/exploration/commercial/cargo/orbitalsciences-index.html)

"There is a 45 percent chance of favorable weather at the time of launch. Low clouds are the primary concern for a weather violation."

Title: Re: Antares A-One General Discussion Thread (2)
Post by: jcm on 04/17/2013 12:48 PM
A-ONE is the mission name, but is the rocket's tail number 1, or 2?  (following the pathfinder vehicle).
Title: Re: Antares A-One General Discussion Thread (2)
Post by: FinalFrontier on 04/17/2013 12:54 PM
Quick question will orbital be doing any sort of webcast or will the only coverage be NASA TV?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/17/2013 01:11 PM
Quick question will orbital be doing any sort of webcast or will the only coverage be NASA TV?

No Orbital webcast. NASA TV will webcast.

Edit: Chris, sorry, didn't realize reference to (unnamed) website was verboten...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/17/2013 01:13 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: collectSPACE on 04/17/2013 01:19 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?

According to Orbital, there are cameras on the first stage (looking down), and on the second stage (for stage and fairing separation). The first stage view will be available live but as the second stage events will be after Antares flies past the horizon, they will downlink those feeds later, after the second stage is in space.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: edkyle99 on 04/17/2013 01:26 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?

According to Orbital, there are cameras on the first stage (looking down), and on the second stage (for stage and fairing separation). The first stage view will be available live but as the second stage events will be after Antares flies past the horizon, they will downlink those feeds later, after the second stage is in space.
A good time to remind ourselves not to be surprised when the second stage doesn't ignite after first stage separation.  It will coast first, for 1 minute 24 seconds after separation, which itself comes five seconds after first stage shut down.

 - Ed Kyle
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/17/2013 01:58 PM
From the update thread:
Orbital Sciences ‏@OrbitalSciences
Launch prep at #NASA_Wallops continues. The #Antares vehicle team completed final arming and close out activities last night at 9 PM EDT.
@OrbitalSciences: The launch team will arrive on console at approximately 8:45 AM.  The count will pick up at 9 AM with an anticipated T-0 of 5 PM EDT.

Does the completion of close out activities mean that the remaining activities are all of the button-pushing type rather than the wrench-turning type? What's left to do today before launch?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: block51 on 04/17/2013 02:09 PM
Does the completion of close out activities mean that the remaining activities are all of the button-pushing type rather than the wrench-turning type? What's left to do today before launch?

I can't speak to every activity that is involved, but I know there was some physical turning of wrenches that needed to go on. We had some close out personnel come by our building yesterday morning (The contract I'm on at WFF  is headed by Orbital, though a different division) needing to borrow several taps to clean out some threaded holes on the pad. Further, a ground safety friend of mine made a comment on facebook last night talking about being OSS for arming operations. More than just button pushing and paperwork (though I'm sure there is plenty of that as well!).
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/17/2013 03:08 PM
Hmm, strange......

Quote
Ben Cooper ‏@LaunchPhoto
For the record, once O2 tanking were to begin, launch window reduced to 15 minutes.  #Antares

A bug (feature?) inherited from Zenit? (which almost always launches without scrubs)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/17/2013 03:10 PM
No - a feature of the AJ26 (sub-cooled LOX)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lar on 04/17/2013 03:13 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?

According to Orbital, there are cameras on the first stage (looking down), and on the second stage (for stage and fairing separation). The first stage view will be available live but as the second stage events will be after Antares flies past the horizon, they will downlink those feeds later, after the second stage is in space.
IIRC it was said that some of the cameras are pointing at internal things that are "only of interest to engineers" rather than external views.

PS: Good luck, Orbital...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/17/2013 03:17 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?

According to Orbital, there are cameras on the first stage (looking down), and on the second stage (for stage and fairing separation). The first stage view will be available live but as the second stage events will be after Antares flies past the horizon, they will downlink those feeds later, after the second stage is in space.
A good time to remind ourselves not to be surprised when the second stage doesn't ignite after first stage separation.  It will coast first, for 1 minute 24 seconds after separation, which itself comes five seconds after first stage shut down.

 - Ed Kyle

thanks for the heads up on that Ed, should be a very interesting launch.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Ben the Space Brit on 04/17/2013 03:35 PM
Will there be cameras on the rocket's first and second stages? Will there be live views from the rocket during the launch?

According to Orbital, there are cameras on the first stage (looking down), and on the second stage (for stage and fairing separation). The first stage view will be available live but as the second stage events will be after Antares flies past the horizon, they will downlink those feeds later, after the second stage is in space.
A good time to remind ourselves not to be surprised when the second stage doesn't ignite after first stage separation.  It will coast first, for 1 minute 24 seconds after separation, which itself comes five seconds after first stage shut down.

 - Ed Kyle

thanks for the heads up on that Ed, should be a very interesting launch.

It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Space Pete on 04/17/2013 03:50 PM
As we get nearer to launch, you can track all aircraft in the vicinity of Wallops here:

http://flightaware.com/live/airport/KWAL
Title: Re: Antares A-One General Discussion Thread (2)
Post by: edkyle99 on 04/17/2013 03:55 PM
It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?
I wouldn't call it just a "kick stage".  It is a bonafide stage powered by a sizable solid motor.  This 14 tonne motor (twice as heavy as a Delta 2 second stage) burns for 155 seconds, one of the longest-burning solid motors I can recall.  It works at better than 301 seconds ISP.  It has a composite case and a big nozzle, so it is very mass and fuel efficient.

 - Ed Kyle

Title: Re: Antares A-One General Discussion Thread (2)
Post by: hrissan on 04/17/2013 04:48 PM
It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?
I wouldn't call it just a "kick stage".  It is a bonafide stage powered by a sizable solid motor.  This 14 tonne motor (twice as heavy as a Delta 2 second stage) burns for 155 seconds, one of the longest-burning solid motors I can recall.  It works at better than 301 seconds ISP.  It has a composite case and a big nozzle, so it is very mass and fuel efficient.

 - Ed Kyle
I understand that the total energy is conserved during coasting, but does the long coast phase means there would be excess vertical velocity after S1 MECO? Then why the trajectory is not lowered during the first stage flight?

Can someone explain why coasting for so long?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/17/2013 05:20 PM

I understand that the total energy is conserved during coasting, but does the long coast phase means there would be excess vertical velocity after S1 MECO? Then why the trajectory is not lowered during the first stage flight?

Can someone explain why coasting for so long?

To get the vehicle at the proper orbital parameters (altitude and perigee) at burn out. 
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Space Pete on 04/17/2013 05:21 PM
Just want to say that I am absolutely loving Orbital's PR today - both from the internal people who are graciously taking the time to post on this forum, and from Orbital's Twitter account, which is posting minute-by-minute technical updates, and is replying to people who Tweet them to wish them luck (including me)! :)

It's more like what I remember of Shuttle launches, where there was never a quiet minute once we got past L-5h or so. I wish SpaceX could be more like this - Orbital seem to be able to do it without revealing ITAR/proprietary information.

Well done to Orbital PR!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/17/2013 05:23 PM

I understand that the total energy is conserved during coasting, but does the long coast phase means there would be excess vertical velocity after S1 MECO? Then why the trajectory is not lowered during the first stage flight?

Can someone explain why coasting for so long?

To get the vehicle at the proper orbital parameters (altitude and perigee) at burn out. 

Would the 1st stage be recoverable if they used chutes?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: PahTo on 04/17/2013 05:49 PM

Glad to see the team moving forward with prop loading ops despite the weather.  As we've seen many times, better to be ready in case the weather is acceptable.  Bonus is they get more experience and more info each time they do these functions.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: PahTo on 04/17/2013 06:02 PM

Cross-posting from party thread:

Will this mark the first orbital flight for the NK-33?  Yes, I know they're AJ-26, but from a heritage standpoint, will this be the first time this engine boosts an orbital payload?
Thanks!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/17/2013 06:11 PM

Cross-posting from party thread:

Will this mark the first orbital flight for the NK-33?  Yes, I know they're AJ-26, but from a heritage standpoint, will this be the first time this engine boosts an orbital payload?
Thanks!

Since the NK-33 was not used on the N-1 launches (they used the less powerful NK-15), the answer is yes.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kaputnik on 04/17/2013 08:31 PM
Apologies if this was asked already, but are there any holds in this countdown?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lar on 04/17/2013 09:05 PM
Apologies if this was asked already, but are there any holds in this countdown?

The pdf of the visitor presentation deck shows several[1].. see slide 20 for a timeline... reproduced here

L-08H 00M: Call to stations
L-07H 30M: Voice checks
L-07H 00M: Range and facility set up
L-06H 30M: Pad clear
L-06H 00M: OCCS sequencer initiation/warm helium charging
L-05H 50M: Vehicle power up and systems checks
L-03H 40M: 15 minute hold
L-03H 00M: Start of LOLS chilldown
L-01H 45M: 15 minute hold
T-01H 30M: Start of propellant loading
T-00H 25M: Start of engine low flow chilldown
T-00H 10M: Start of engine medium flow chilldown
T-00H 03M 30S: Initiate autosequencer transition (terminal count)
T-00H 03M 00S: Autosequencer control
T-00H 00M 00.5S: Initiation launch ordnance train
T-00H 00M 00S: Launch (1700 EDT)
T+1.5 seconds: Engine health checks complete
T+2 seconds: Liftoff
L+6 seconds: TEL clear

1 - well... two anyway. Which is "several" for sufficiently large values of 2 or small values of "several" :)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: zt on 04/17/2013 09:27 PM


U+F098 is a private use unicode character (http://en.wikipedia.org/wiki/Private_Use_%28Unicode%29), not universally defined to mean anything. You shouldn't use it on the open web.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/17/2013 09:36 PM
It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?

You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.

Lastly, it is not a high ISP solution.

I always thought that solids are good as either high-thrust boosters, or BEO kick stages since they are simple and can last a long time in orbit.

Anyone familiar with why they went with a solid U/S?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: rayleighscatter on 04/17/2013 09:37 PM
the frontpage update here says Friday is the last shot for the month. I thought the launch window ran through Sunday?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/17/2013 09:45 PM


You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.

Lastly, it is not a high ISP solution.

I always thought that solids are good as either high-thrust boosters, or BEO kick stages since they are simple and can last a long time in orbit.

Anyone familiar with why they went with a solid U/S?

Cost and it is in the Antares threads that you should spend more time on.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lar on 04/17/2013 09:48 PM


U+F098 is a private use unicode character (http://en.wikipedia.org/wiki/Private_Use_%28Unicode%29), not universally defined to mean anything. You shouldn't use it on the open web.

It's what I got when I cut'n'paste from Orbital's PDF,,, not something I made up myself. No idea why they were using it (or the software chain translated to that character on the way from the PDF source through a linux box Acrobat Reader, to my cut/paste buffer to FireFox and to your terminal)

If it's really bothering you I'll edit it out of my post :)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/17/2013 09:51 PM


Anyone familiar with why they went with a solid U/S?

IIRC, Antonio said they decided that doing a liquid first stage for the first time (for Orbital) was enough of a challenge, and that trying to simultaneously develop a liquid upper stage would have been biting off more than they could chew. An off-the-shelf solid was a lower technical and schedule risk proposition.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kaputnik on 04/17/2013 10:07 PM


Anyone familiar with why they went with a solid U/S?

IIRC, Antonio said they decided that doing a liquid first stage for the first time (for Orbital) was enough of a challenge, and that trying to simultaneously develop a liquid upper stage would have been biting off more than they could chew. An off-the-shelf solid was a lower technical and schedule risk proposition.

And also it was at one point planned to upgrade to a liquid U/S using, IIRC, a Soyuz engine. I believe that plan is shelved at present though (shame!)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: happyflower on 04/17/2013 10:16 PM
Why is it that Russians launch rockets in the middle of a snow storm / blizzard but in the US we have to worry about low cloud cover?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/17/2013 10:22 PM
1. Would weather have aborted the launch if the umbilical hadn't?

2. What are weather violation probabilities for the next few days?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/17/2013 10:25 PM


Anyone familiar with why they went with a solid U/S?

IIRC, Antonio said they decided that doing a liquid first stage for the first time (for Orbital) was enough of a challenge, and that trying to simultaneously develop a liquid upper stage would have been biting off more than they could chew. An off-the-shelf solid was a lower technical and schedule risk proposition.

ok, thanks - that makes more sense.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: PreferToLurk on 04/17/2013 10:26 PM
Are we looking at a wind limitation pending a strengthening or redesign?

http://forum.nasaspaceflight.com/index.php?topic=31663.msg1039886#msg1039886

Above post indicates that the wind limit was raised prior to the scrub.

IMHO, the short term fix is to review the testing data for the strongback to ensure that nothing was missed, and then don't issue the waiver next time.

Long term redesigns (if necessary) would wait for a future launch.

Any reason to believe otherwise?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/17/2013 10:27 PM


You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.

Lastly, it is not a high ISP solution.

I always thought that solids are good as either high-thrust boosters, or BEO kick stages since they are simple and can last a long time in orbit.

Anyone familiar with why they went with a solid U/S?

Cost and it is in the Antares threads that you should spend more time on.

Why?  (I did read some of them.)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: strangequark on 04/17/2013 10:32 PM
You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.
This is actually kind of a misconception when you're talking about composite solids. The PMF on the Castor 30 is 0.926, which is pretty damn good (you can confirm this yourself, if you search for the ATK Motor Catalog).

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.
Yes, but modern GNC is pretty skilled at minimizing this uncertainty to the point where it's a non-issue for the payload to take up the slack.

Lastly, it is not a high ISP solution.
This point I will still give you. Even the kerosene upper stage engines are pretty good by comparison.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/17/2013 10:47 PM


Anyone familiar with why they went with a solid U/S?

IIRC, Antonio said they decided that doing a liquid first stage for the first time (for Orbital) was enough of a challenge, and that trying to simultaneously develop a liquid upper stage would have been biting off more than they could chew. An off-the-shelf solid was a lower technical and schedule risk proposition.

And also it was at one point planned to upgrade to a liquid U/S using, IIRC, a Soyuz engine. I believe that plan is shelved at present though (shame!)

Yes, since the 30XL will improve performance and the Star 48 can be stacked on top as well. No business case to develop an (expensive) cryo 2nd stage at this point in the game.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Big Al on 04/17/2013 11:09 PM
Since the Star family of engines has been around for a long time, It's burn profile is well known.
Also since their capsule is not equipped with a heat shield, they should be able to carry more payload for the same weight.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/17/2013 11:14 PM
Why is it that Russians launch rockets in the middle of a snow storm / blizzard but in the US we have to worry about low cloud cover?

visibility for Range safety
Title: Re: Antares A-One General Discussion Thread (2)
Post by: jsmjr on 04/17/2013 11:14 PM
From the closed processing thread:

I note the mission timeline viewgraph at the briefing shows a launch azimuth of 107.8 deg. But the actual hazard area seems to be more like an azimuth of 124 deg, and it needs to turn to an azimuth of 134 deg or so to reach the target inclination.

Does anyone have a screen shot of the cited slide? 

And any confirmation of what's going on here, doglegging like that?  Is it a function of the way the vehicle sits on the pad?  How quickly does it turn?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/17/2013 11:43 PM

Yes, since the 30XL will improve performance and the Star 48 can be stacked on top as well. No business case to develop an (expensive) cryo 2nd stage at this point in the game.

Well, the business case has to do with the capacity of the overall rocket.

Right now, Antares can lift about as much as the F5 was supposed to, but that was a market spot that proved unsuccessful. 

Part of the reason for this performance is the second stage. (The ISP, 7.3% dry weight)

Also, the flip side of the business equation is cost.  Development cost may have been lower, but overall I believe the rocket is more expensive.

Correct me if I'm wrong, but at the price/capacity of Antares, is it competitive in the commercial arena?

Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/18/2013 01:00 AM
It is a Delta II replacement.

It wasn't the market that killed F5, it couldn't  do a Dragon spacecraft was the reason.  The market still exists.  See the last Delta II sold.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/18/2013 03:05 AM
It is a Delta II replacement.

It wasn't the market that killed F5, it couldn't  do a Dragon spacecraft was the reason.  The market still exists.  See the last Delta II sold.

But isn't that setting the bar pretty low in terms of commercial market?

The Delta II is a pretty expensive rocket isn't it?

I'm looking here:  http://en.wikipedia.org/wiki/List_of_Thor_and_Delta_launches_(2010%E2%80%932019)

And I don't know which is the last sale you're referring to, but it looks like 4-5 launches a year, mostly small government payloads.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/18/2013 03:24 AM

But isn't that setting the bar pretty low in terms of commercial market?

The Delta II is a pretty expensive rocket isn't it?


Not commercial market, but market.  Delta II also did Globalstar and Iridium constellations.

It beat out F9 for 4 launches.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/18/2013 05:15 AM

But isn't that setting the bar pretty low in terms of commercial market?

The Delta II is a pretty expensive rocket isn't it?


Not commercial market, but market.  Delta II also did Globalstar and Iridium constellations.

It beat out F9 for 4 launches.

So this answers the "why" from a few posts ago.  A new rocket is always fun, but if the upside is just a delta II replacement then it's less exciting to me than what's in those other forums you complain that I frequent too much...

And beating out the newcomer on some government flights is really not a major bragging point. OSC has been around for much longer, and so it's their lead to lose.

But hey - the more the merrier, and I really don't see these two companies headed for the same market area, so there isn't even real competition.  There's some overlap on ISS cargo delivery, but in the grand scheme of things, they can't survive on that alone.  The whole point is that they find other markets, and it looks like they all can, so beers all around.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mikes on 04/18/2013 07:49 AM
Why is it that Russians launch rockets in the middle of a snow storm / blizzard but in the US we have to worry about low cloud cover?

visibility for Range safety

Are there also concerns about reflected sound, or is Antares too small for that to be a problem?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kim Keller on 04/18/2013 11:58 AM
Are there also concerns about reflected sound, or is Antares too small for that to be a problem?


There was discussion of that during the count.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: kevin-rf on 04/18/2013 01:16 PM

So this answers the "why" from a few posts ago.  A new rocket is always fun, but if the upside is just a delta II replacement then it's less exciting to me than what's in those other forums you complain that I frequent too much...

Other than, which is in the Orbital threads somewhere, at that point in time ULA had it's EELV solutions, but the (at that point) lower cost Delta II left a capability gap that Orbital feared would jack up the launch prices of Delta II class sized payloads that must fly on US launchers, thus putting many of these payloads into a cost death spiral that would cost Orbital Delta II sized satellite business. Orbital did not get into the business to challenge established launch providers, but to fill a gap that they feared would cost them satellite contracts. Hence the Antares was born.

And if you want to put a SpaceX spin on it, they feared the then plans of SpaceX would not meet the Delta II class payload needs of it's satellite business. If they had confidence in SpaceX, they most likely would not have built the Antares.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lurker Steve on 04/18/2013 01:34 PM

Yes, since the 30XL will improve performance and the Star 48 can be stacked on top as well. No business case to develop an (expensive) cryo 2nd stage at this point in the game.

Well, the business case has to do with the capacity of the overall rocket.

Right now, Antares can lift about as much as the F5 was supposed to, but that was a market spot that proved unsuccessful. 

Part of the reason for this performance is the second stage. (The ISP, 7.3% dry weight)

Also, the flip side of the business equation is cost.  Development cost may have been lower, but overall I believe the rocket is more expensive.

Correct me if I'm wrong, but at the price/capacity of Antares, is it competitive in the commercial arena?



I took my non-rocket scientist look at the second stage and was actually suprised. The Castor 30 motor actually supplies more total thrust than any equivalent liquid second stage (including both the engine and motor) of comparable launch weight. It wasn't really even close.

The only issue I see with a solid second stage is that you lose the ability to restart because you really only get a single burn. That means it's near impossible to deploy multiple payloads from the same LV. Of course, since the launcher isn't oversized anyway, that's not an issue.

Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/18/2013 01:59 PM
Back to the launch attempt...has there been any discussion of an irregular shaped white piece of material that appears to be falling off the strongback? It appears in the gif that LeeJay posted on pg 11 of the Updates thread, in the second frame of the gif. It partially obscures a horizontal member of the strongback, at a height between the A and N of Antares. It doesn't appear in frame 1, then does appear in frame 2.

Maybe some rational explanation for it, but I can't figure it out.

Edit: after looking at the video, it looks like a piece of material that was attached to the strongback and can be seen fluttering in the breeze. The first frame of LeeJay's gif that doesn't show it must have been from a different time in the count.

Edit 2: shortly after the LD calls "meet me on Anomaly 1," a white piece of material appears to fall off the fwd end of stage 1 and flutters to the ground. Shortly after that, another white piece of material falls off and hangs up on an upper horizontal member of the strongback (this is the piece I first noticed). Wondering if these are decals that fell off. IIRC someone else mentioned they were having a problem with decals adhering.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Nickolai on 04/18/2013 02:04 PM
Good question Kabloona. Looks like it might have some red paint on it?

Unrelated question - could somebody talk about the orbital mechanics going on here? Apparently, if Friday doesn't work out, it's the last opportunity for 'this part of the month' - why doesn't a launch window to a 51.6 degree orbit open every day?

And since this is just a test flight with a dummy payload, what does it matter what orbit they go to? Or is the target orbit driven by the secondary payloads?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: douglas100 on 04/18/2013 02:11 PM

The only issue I see with a solid second stage is that you lose the ability to restart because you really only get a single burn. That means it's near impossible to deploy multiple payloads from the same LV. Of course, since the launcher isn't oversized anyway, that's not an issue.

There is an option for a bi-propellant third stage which might address that need.

http://www.orbital.com/NewsInfo/Publications/Antares_Brochure.pdf (http://www.orbital.com/NewsInfo/Publications/Antares_Brochure.pdf)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: LouScheffer on 04/18/2013 02:27 PM

I took my non-rocket scientist look at the second stage and was actually suprised. The Castor 30 motor actually supplies more total thrust than any equivalent liquid second stage (including both the engine and motor) of comparable launch weight. It wasn't really even close.


The problem with this analysis is that thrust is not the right metric - you want total velocity change, or delta-V.  A liquid stage might give you 1/5 the thrust, but for 7 times longer, and be a better deal. 
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mr. mark on 04/18/2013 02:30 PM
Antares has been on the pad a while. We don't need another corroded nut.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Antares on 04/18/2013 02:52 PM
Unrelated question - could somebody talk about the orbital mechanics going on here? Apparently, if Friday doesn't work out, it's the last opportunity for 'this part of the month' - why doesn't a launch window to a 51.6 degree orbit open every day?

And since this is just a test flight with a dummy payload, what does it matter what orbit they go to? Or is the target orbit driven by the secondary payloads?

Wallops Range availability is the driver.  Orbital targeting has no impact.  Note the launch time doesn't change with the launch date.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lar on 04/18/2013 02:54 PM
It beat out F9 for 4 launches.

Which 4? Was F9 really a contender? Contradicts what Ms. Shotwell said about winning everything they competed for.


But hey - the more the merrier, and I really don't see these two companies headed for the same market area, so there isn't even real competition.  There's some overlap on ISS cargo delivery, but in the grand scheme of things, they can't survive on that alone.  The whole point is that they find other markets, and it looks like they all can, so beers all around.

Roger that. To SpaceX, ISS Cargo is just a happy thing that came along, is my thinking... They were glad to bid on it and it gives them some paid for flights but it's not their long term bread and butter.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/18/2013 03:13 PM

And if you want to put a SpaceX spin on it, they feared the then plans of SpaceX would not meet the Delta II class payload needs of it's satellite business. If they had confidence in SpaceX, they most likely would not have built the Antares.

...  no, not really.  I wasn't the one who brought it up, I was here mainly to see how the rocket did and why it's built the way it is.

Back to our regularly scheduled programming.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: kevin-rf on 04/18/2013 03:36 PM
I agree... Looking forward to the launch, hopefully the decals don't peel like a banana.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/18/2013 03:45 PM

So this answers the "why" from a few posts ago.  A new rocket is always fun, but if the upside is just a delta II replacement then it's less exciting to me than what's in those other forums you complain that I frequent too much...

Other than, which is in the Orbital threads somewhere, at that point in time ULA had it's EELV solutions, but the (at that point) lower cost Delta II left a capability gap that Orbital feared would jack up the launch prices of Delta II class sized payloads that must fly on US launchers, thus putting many of these payloads into a cost death spiral that would cost Orbital Delta II sized satellite business. Orbital did not get into the business to challenge established launch providers, but to fill a gap that they feared would cost them satellite contracts. Hence the Antares was born.

And if you want to put a SpaceX spin on it, they feared the then plans of SpaceX would not meet the Delta II class payload needs of it's satellite business. If they had confidence in SpaceX, they most likely would not have built the Antares.

good business plan for Orbital
 
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea.  See the Naro update I posted. 
 
http://forum.nasaspaceflight.com/index.php?topic=27497.msg1040327#msg1040327 (http://forum.nasaspaceflight.com/index.php?topic=27497.msg1040327#msg1040327)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/18/2013 03:50 PM

So this answers the "why" from a few posts ago.  A new rocket is always fun, but if the upside is just a delta II replacement then it's less exciting to me than what's in those other forums you complain that I frequent too much...

Other than, which is in the Orbital threads somewhere, at that point in time ULA had it's EELV solutions, but the (at that point) lower cost Delta II left a capability gap that Orbital feared would jack up the launch prices of Delta II class sized payloads that must fly on US launchers, thus putting many of these payloads into a cost death spiral that would cost Orbital Delta II sized satellite business. Orbital did not get into the business to challenge established launch providers, but to fill a gap that they feared would cost them satellite contracts. Hence the Antares was born.

And if you want to put a SpaceX spin on it, they feared the then plans of SpaceX would not meet the Delta II class payload needs of it's satellite business. If they had confidence in SpaceX, they most likely would not have built the Antares.

good business plan for Orbital
 
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea.  See the Naro update I posted. 

I doubt the Koreans are a threat - their launcher will be late to the party and obviously is mainly for domestic use. Same with the Japanese.

Now the Chinese and Indians and Italians? This is another story.... however Antares stands at a good position of being US based, so I can see it and the F9 bisecting the old Delta market, with a few Atlas V thrown into the measure.

Anyway this may be a better topic in the Antares general thread and not in the A-ONE thread....
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/18/2013 07:24 PM

So this answers the "why" from a few posts ago.  A new rocket is always fun, but if the upside is just a delta II replacement then it's less exciting to me than what's in those other forums you complain that I frequent too much...

Other than, which is in the Orbital threads somewhere, at that point in time ULA had it's EELV solutions, but the (at that point) lower cost Delta II left a capability gap that Orbital feared would jack up the launch prices of Delta II class sized payloads that must fly on US launchers, thus putting many of these payloads into a cost death spiral that would cost Orbital Delta II sized satellite business. Orbital did not get into the business to challenge established launch providers, but to fill a gap that they feared would cost them satellite contracts. Hence the Antares was born.

And if you want to put a SpaceX spin on it, they feared the then plans of SpaceX would not meet the Delta II class payload needs of it's satellite business. If they had confidence in SpaceX, they most likely would not have built the Antares.

good business plan for Orbital
 
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea.  See the Naro update I posted. 

I doubt the Koreans are a threat - their launcher will be late to the party and obviously is mainly for domestic use. Same with the Japanese.



not a threat, but a competitor.  Hope you watched the video I posted. The video was the chopped down version from what I saw the other night.
 
Their plans are to move way past "domestic use" and offer complete packages.  Also if SK has a copy = to Russia's next generation engine then Russia needs to move quicker IMHO.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/18/2013 07:26 PM

 
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea. 

Not at all
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/18/2013 07:45 PM

 
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea. 

Not at all

Believe it Jim, they have Sat platforms (on the shelf) and launch services under construction.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Jim on 04/18/2013 07:47 PM

Believe it Jim, they have Sat platforms (on the shelf) and launch services under construction.

That doesn't mean it is competition.
Your point is unsubstantiated.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/18/2013 07:59 PM

Believe it Jim, they have Sat platforms (on the shelf) and launch services under construction.

That doesn't mean it is competition.
Your point is unsubstantiated.

When they take the Sat platforms and start to sell them (in the plans) then it is competition.   Sides the administration signed off on much of this with the "Free trade agreement" I haven't read it, however I do watch the S.Korea news (its retransmitted local).  Can tell the competition is coming. 
 
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mlindner on 04/18/2013 08:02 PM

Believe it Jim, they have Sat platforms (on the shelf) and launch services under construction.

That doesn't mean it is competition.
Your point is unsubstantiated.

Agreeing with Jim here (wow). I'd be surprised if SK could beat out the Chinese let alone SpaceX. They're another government launcher with powerpoint plans for commercial.

We're getting off topic though.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lars_J on 04/18/2013 08:49 PM
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea. 

With what launch vehicle?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Zed_Noir on 04/18/2013 09:12 PM
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea. 

With what launch vehicle?

Never mind "what launch vehicle". The South Koreans doesn't even have a suitable engine available.

Back on topic. Orbital at least have the NK33 stockpile available to base their launch vehicle on, when they got the late entry into the COTS program..
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/19/2013 12:44 AM
But Orbital, SpaceX, ULA and Russia will have some major competition coming from SKorea. 

With what launch vehicle?

Never mind "what launch vehicle". The South Koreans doesn't even have a suitable engine available.

Back on topic. Orbital at least have the NK33 stockpile available to base their launch vehicle on, when they got the late entry into the COTS program..

sorry didn't wish to take it off topic.....too much excitement with new engines.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/20/2013 02:58 PM
From update thread:
Early WX balloon run of the Overpressure safety criteria (which was marginal on Wed) was reported as "good."  It's the last balloon before launch that counts, though...

1. What's the overpressure safety criteria?

2. Do you need to get a clearance from FAA flight controllers for a weather balloon launch? I suspect a weather balloon is too small for regulation under FAA Part 101 (http://www.chem.hawaii.edu/uham/part101.html).
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/20/2013 04:15 PM
The FAA we are talking about is not "aeronautical" FAA but "space" FAA ("Code 700").  One of te conditions for the launch license is the "Focused Blast Overpressure" risk (read: glass shards from broken windows hurting people) which depoends on atmospheric conditions that are measured by weather balloons.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: input~2 on 04/20/2013 04:45 PM
NOTAM
Quote
!CARF 04/109 (KZNY A0226/13)  ZNY AIRSPACE DCC ANTARES ONE  STATIONARY RESERVATION WITHIN AN AREA BNDD BY 2657N/6014W 2807N/5848W  1834N/5030W 1814N/5058W 1814N/5212W SFC-UNL WEF 1304202100-1304210030
Title: Re: Antares A-One General Discussion Thread (2)
Post by: edkyle99 on 04/20/2013 04:54 PM
It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?

You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.

Lastly, it is not a high ISP solution.

I always thought that solids are good as either high-thrust boosters, or BEO kick stages since they are simple and can last a long time in orbit.

Anyone familiar with why they went with a solid U/S?
As Jim answered, the answer is "cost".  The ultimate Antares second stage will be Castor 30XL, a stretched version that reportedly only cost $57 million to develop.  That's probably not much more than it costs to build and fly one or two Centaur stages.  Centaur, of course, cost far more than $57 million to develop, but that cost has been amortized over decades of flights by many stages now.  Orbital did not have that luxury.

Speaking of Centaur, Castor 30XL will have a better propellant mass ratio than that well-regarded and very successful liquid hydrogen upper stage.  That "high dry weight" often associated with solid motors does not apply in this case, nor for many of the modern day solid motors.

Centaur, of course will generate much more specific impulse than Castor 30XL, but the improved Antares second stage will still produce more than 75% as much total impulse as Centaur.  Castor 30XL will produce 3.8 times more total impulse than the Delta 2 second stage while having a far better PMF than that pressure fed stage. 

Castor 30XL is a high performance graphite epoxy case solid motor with a huge nozzle designed to extract maximum performance.  It provides that performance without need for any cryogenic propellant handling or loading at the pad.  It is a good deal for Orbital, which is trying hard to develop a rocket that can make money flying only a few times per year. 

 - Ed Kyle
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/20/2013 04:55 PM
Kudos to the Orbital PR team after a little bit behind during their previous coverage - they are noting little details on the pre-launch timeline that I have never heard of in any launch I have seen (not even Shuttle launches!). They are even reporting what temperature the payload ECS have been adjusted to (80F) or that the team was reviewing simulated telemetry displays!  8)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: input~2 on 04/20/2013 05:12 PM
Notice to Mariners
Title: Re: Antares A-One General Discussion Thread (2)
Post by: blazotron on 04/20/2013 06:25 PM
Centaur, of course will generate much more specific impulse than Castor 30XL, but the improved Antares second stage will still produce more than 75% as much total impulse as Centaur.  Castor 30XL will produce 3.8 times more total impulse than the Delta 2 second stage while having a far better PMF than that pressure fed stage. 

I don't understand the focus on total impulse of the second stage.  Total impulse is not a non-dimensional figure of merit of a stage, just a result (primarily) of the size, which depends on the design of the entire rocket.  It's apples to oranges to compare the stages of two different rockets which may have vastly different staging ratios, thrust-to-weight, and total payload to orbit performance, etc.  The Saturn V's second stage (S-II) had a far higher total impulse than Centaur or Castor (of any flavor), but that doesn't make it "better".
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/20/2013 06:35 PM
Try carrying a 10MT load on a Lamborghini...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lee Jay on 04/20/2013 06:59 PM
What is the root cause of the 15 minute maximum hold time once propellant loading has begun?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/20/2013 07:06 PM
Subcooled LOX warms up (no in-tank cooling or recirculating capability - LOX is chilled as it goes in)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lee Jay on 04/20/2013 07:12 PM
Subcooled LOX warms up (no in-tank cooling or recirculating capability - LOX is chilled as it goes in)

Ah...thanks.  So, it's below its boiling point?  Is that for densification or some other reason?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/20/2013 07:45 PM
NK-33's were designed for subcooled LOX ... LOX-cooled pump bearings are not amused by boiling-point LOX ...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lee Jay on 04/20/2013 07:48 PM
NK-33's were designed for subcooled LOX ... LOX-cooled pump bearings are not amused by boiling-point LOX ...

Yup...that sound's like a hard limit to me.  Thanks again!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/20/2013 07:51 PM
Anyone know off hand what time sunset is at MARS?   
 
Sounds like this Antares is going to light up the east coast!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/20/2013 07:52 PM
Sunset 19:43 EDT
Title: Re: Antares A-One General Discussion Thread (2)
Post by: SoCalEric on 04/20/2013 09:24 PM
By the way, does anyone know if  this flight carrying the phonesat demonstrations?

http://www.nasa.gov/directorates/spacetech/small_spacecraft/phonesat.html

"Three NASA PhoneSats systems (two PhoneSat 1.0's and one PhoneSat 2.0) are scheduled to launch aboard the maiden flight of Orbital Sciences Corporation's Antares rocket from NASA's Wallops Flight Facility at Wallops Island, Va., in early 2013."
Title: Re: Antares A-One General Discussion Thread (2)
Post by: patchfree on 04/20/2013 09:25 PM
Why this live thread is here and not in the live events section?!!
Very curious and not in line with the usual way!!!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ChrisC on 04/20/2013 09:28 PM
Culbertson headed for press conference at 17:15 EDT

Is this on NASA TV?  Can't find it, even on Media channel.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Silmfeanor on 04/20/2013 09:29 PM
Why this thread is here and not in the live events section?!!
Very curious and not in line with the usual way!!!

nope, this is the usual way. Sometimes Chris posts a link there, though. SpaceX threads werent in the live section - they have their own section. So do Orbital threads.

On topic - Good luck to orbital, I hope the weather gods favor you on sunday. And thanks for the heap of inside info. Time to read up on subcooled lox!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: pericynthion on 04/20/2013 09:43 PM
By the way, does anyone know if  this flight carrying the phonesat demonstrations?

http://www.nasa.gov/directorates/spacetech/small_spacecraft/phonesat.html

"Three NASA PhoneSats systems (two PhoneSat 1.0's and one PhoneSat 2.0) are scheduled to launch aboard the maiden flight of Orbital Sciences Corporation's Antares rocket from NASA's Wallops Flight Facility at Wallops Island, Va., in early 2013."

Yes, they are on this flight.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Gary NASA on 04/20/2013 09:45 PM
By the way, does anyone know if  this flight carrying the phonesat demonstrations?

http://www.nasa.gov/directorates/spacetech/small_spacecraft/phonesat.html

"Three NASA PhoneSats systems (two PhoneSat 1.0's and one PhoneSat 2.0) are scheduled to launch aboard the maiden flight of Orbital Sciences Corporation's Antares rocket from NASA's Wallops Flight Facility at Wallops Island, Va., in early 2013."

Did you really not read the launch overview article?

http://www.nasaspaceflight.com/2013/04/orbital-antares-debut-launch-attempt/

Quote
In addition to the mass simulator, A-ONE is also carrying four small satellites as secondary payloads. All four are CubeSats, which will be deployed using ISIPod dispensers.

Dove-1 is a three-unit (3U) CubeSat which will be operated by Cosmogia Incorporated. It is a technology demonstrator, intended to test a new CubeSat bus incorporating off-the-shelf hardware. It will be the second of Cosmogia’s Dove satellites to launch; Dove 2 was launched aboard a Soyuz-2-1a on Friday.

PhoneSat is a NASA technology demonstration experiment to examine basing satellites’ onboard systems around off-the-shelf mobile telephone technology.

It is hoped that the use of off-the-shelf technology will reduce the cost of future small satellite missions; the PhoneSat spacecraft are among the cheapest ever built, with a budget of $3,500 per satellite for PhoneSat-1.0 spacecraft and $8,000 for PhoneSat-2.0s, excluding launch costs.

Three PhoneSat spacecraft are aboard the A-ONE mission: PhoneSat-1.0a, 1.0b and 2.0a. PhoneSat-1.0 satellites are based around HTC Nexus One phones, while PhoneSat-2.0 satellites use Samsung Nexus-S phones. Each PhoneSat is a single-unit (1U) CubeSat.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Chris Bergin on 04/20/2013 09:49 PM
Why this live thread is here and not in the live events section?!!
Very curious and not in line with the usual way!!!

Same as SpaceX, same as Shuttle. They stay in their dedicated sections.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: MP99 on 04/21/2013 10:25 AM
The FAA we are talking about is not "aeronautical" FAA but "space" FAA ("Code 700").  One of te conditions for the launch license is the "Focused Blast Overpressure" risk (read: glass shards from broken windows hurting people) which depoends on atmospheric conditions that are measured by weather balloons.

Is this like the inversion layer that caused issues for the first multi-engine test at McGreggor?

cheers, Martin
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 02:47 PM
Since there has been some confusion about how the winds affected our launch attempts and who has authority to wave what, I'd like to offer the following (admittedly a bit pedestrian) explanation:

Surface winds AT THE PAD affect the clearance during lift-off.  Orbital has established a basic 15kts limit for ANY DIRECTION, waivable to 20kts by LD (Eberly).  Eberly has a "pocket reserve" of a few kts if the wind direction is "away from the TEL."  The range helps LD with the go/nogo decision (including computing its effect on POV) but this is not a range decision - it's Orbital's.

Wind SHEAR during ascent induces an angle of attack that changes the aerodynamic load on the vehicle.  This being a first flight, we (Orbital) have rather strict limits on this, which can be alleviated by the choice of trajectory (out of about 5 pre-loaded in the Flight Computer) which can be made as late as L-45m.  Range sends us (Paul Baumgartner and Tracy Chisholm) the balloon data and they (Paul and Tracy) compute the resulting aero loads right at their consoles in the RCC.  Again, an Orbital call - no "single" wind speed limit value.  Not counted on the Weather Officer's POV forecast.

Wind magnitude and direction affect the ground track of trajectory which could bring the vehicle closer to a destruct line than we would be comfortable with.  The trajectories (out of the five mentioned above) that relief aerodynamic loads tend also to be "looser" in terms of lateral position tightness... so, for example, yesterday, only ONE of the trajectories met the aero load criteria (again, yesterday was a 4-sigma day as far as altitude winds were concerned) and that trajectory "grazed" the north destruct line close to the pad.  Again, this is an Orbital call, and Saturday we were ready to fly with that trajectory and those winds (having discussed the trajectory with the FSO who was OK with the grazing.)  Not in the POV.

Now for the part which is NOT under Orbital's discretion: winds and clouds affect three "Public Safety" criteria: Distance Focusing Overpressure (DFO), Toxicity, and Debris.  I don't know a lot about DFO - I believe it is associated with being indoors and a blast breaking the windows and the glass injuring the public.  Toxicity is associated with things such as nitrogen tetroxide, hydrazine and - gulp - plutonium.  We don't have any of these nasty items on THIS flight (Cygnus WILL carry Hydrazine and N2O4.)  Debris is simply pieces of a (supposedly destroyed) rocket falling on undesirable places and is affected by, among other things, population density.

Both the ranges AND the FAA have a "probability of casualty (E sub C)" calculation protocol that is driven by the size and characteristics of the vehicle, the geography of the trajectory, and the atmosphere (winds, clouds, temperature profile, etc.)  The range recalculates these probabilities whenever they launch a balloon.

All U.S. ranges agreed to add up the E sub C of each effect and use a composite criterion (100 per million) as a range go/no go criterion.  FAA on the other hand (I will not comment on why) requires each of the three to be under 30 ppm.  Therefore, you could be OK with the range E sub C but not with the FAA's, as happened on Wednesday (DFO was higher than 30 ppm, toxicity is zero for this vehicle, debris was under 30 ppm) - the composite was well below 100 ppm, so the range was OK, but the DFO was above 30 ppm, so FAA was NOT OK.

In addition, the range can - and does - impose a "no debris expected to fall" area in the VICINITY OF THE RANGE - and the FAA automatically "imposes" the same rule.  There are no "probabilities" in this calculation: it is a "binary" criterion.  Balloon data also drives this calculation.

THIS ONE is what stopped us yesterday: Wallops was willing to do a real-time redraw of the affected area (the souther tip of Assateague Island) that the strong mid-altitude winds created, with the necessary evacuation of the public (some 40 people according to the Fish and Wildlife people that control that area), but FAA was unable to concur in real time.

None of these criteria can be part of the POV since they depend on the complex atmospheric profile that is much, much harder to forecast than, say, surface winds or cloud bases.

I hope this clarifies a bit what is admittedly a very complex situation.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: dawei on 04/21/2013 03:02 PM
Fantastic detail.  Much appreciated.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: block51 on 04/21/2013 03:09 PM
Yes, thanks for the great explanation!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Prober on 04/21/2013 03:16 PM
Fantastic detail.  Much appreciated.

I 2nd this, and would add thanks for taking your time to explain this.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: jsmjr on 04/21/2013 03:29 PM
Fantastic detail.  Much appreciated.

I 2nd this, and would add thanks for taking your time to explain this.

Ditto - and I'd love to hear how those same types of calculations go into the designation of keep-out zones.  Seems to me some of our favorite viewing sites might get closed down on future flights depending on chemicals carried, wind direction, etc.  Did something similar happen mid-countdown yesterday over on Assateague?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/21/2013 03:35 PM
Surface winds AT THE PAD affect the clearance during lift-off.  Orbital has established a basic 15kts limit for ANY DIRECTION, waivable to 20kts by LD (Eberly).  Eberly has a "pocket reserve" of a few kts if the wind direction is "away from the TEL."  The range helps LD with the go/nogo decision (including computing its effect on POV) but this is not a range decision - it's Orbital's.

In the update thread you mentioned a roughly 20% probability of excess surface winds. Are there any other weather criteria that you're particularly concerned about today?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: jnc on 04/21/2013 03:39 PM
I hope this clarifies a bit what is admittedly a very complex situation.

Yes, very much. Thanks again!

Best wishes for today: we've all (I'm sure :-) got our fingers crossed for you all that i) you manage to launch, and ii) that the flight goes well.

Noel
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Lee Jay on 04/21/2013 03:47 PM
All U.S. ranges agreed to add up the E sub C of each effect and use a composite criterion (100 per million) as a range go/no go criterion.

Thank you.

Is this 100 per million launches or 100 per million launch failures?  In other words, does it include or exclude the probability of launch failure?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 03:54 PM
I believe it ASSUMES a failure...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Garrett on 04/21/2013 04:11 PM
Thanks for your excellent post Antonio.

Looking forward to a great launch today!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/21/2013 04:23 PM
It's obviously a very different machine from the ULA launchers or Falcon-9.  Would I be right in saying that the core will get almost all the way to orbit and the U/S is little more than a kick stage to get the perigee up?

You know, I don't understand the choice of a solid U/S.  It seems to have all the wrong attributes for an U/S.

Solids, IIUC, have a high "dry" weight, since the entire "tank" is thick walled.  And in an U/S, every pound wasted is 100% at the expense of payload.

Also, it burns to depletion, so you can't control end-of-burn, so I'd think that precision insertion is problematic.

Lastly, it is not a high ISP solution.

I always thought that solids are good as either high-thrust boosters, or BEO kick stages since they are simple and can last a long time in orbit.

Anyone familiar with why they went with a solid U/S?
As Jim answered, the answer is "cost".  The ultimate Antares second stage will be Castor 30XL, a stretched version that reportedly only cost $57 million to develop.  That's probably not much more than it costs to build and fly one or two Centaur stages.  Centaur, of course, cost far more than $57 million to develop, but that cost has been amortized over decades of flights by many stages now.  Orbital did not have that luxury.

Speaking of Centaur, Castor 30XL will have a better propellant mass ratio than that well-regarded and very successful liquid hydrogen upper stage.  That "high dry weight" often associated with solid motors does not apply in this case, nor for many of the modern day solid motors.

Centaur, of course will generate much more specific impulse than Castor 30XL, but the improved Antares second stage will still produce more than 75% as much total impulse as Centaur.  Castor 30XL will produce 3.8 times more total impulse than the Delta 2 second stage while having a far better PMF than that pressure fed stage. 

Castor 30XL is a high performance graphite epoxy case solid motor with a huge nozzle designed to extract maximum performance.  It provides that performance without need for any cryogenic propellant handling or loading at the pad.  It is a good deal for Orbital, which is trying hard to develop a rocket that can make money flying only a few times per year. 

 - Ed Kyle

Wall, all I can say is the the numbers are pretty harsh.

The 30X has a mass fraction of 7.5%  - I think even the first stage of F9 does better.  (comparing it to old DII upper stage is not a good basis for comparison, is it?)

The unit cost of the US is then going to be higher, right?

Lastly, honestly, $57M doesn't sound that cheap for development cost.

Shrug. 

The point is, after it flies, it needs to compete. 
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/21/2013 04:33 PM
Here's a neat near-real-time graph of wind speeds (and gusts) on the nearby Chincoteague Island: http://www.wunderground.com/weatherstation/WXDailyHistory.asp?ID=KVACHINC2&day=21&month=04&year=2013 . Note that 20 knots = 23 mph.

Weather underground offers a marine forecast for the location "Wallops Island Rocket Launches": http://www.wunderground.com/sailing-weather/beach:Wallops%20Island%20Rocket%20Launches%2039182?MR=1 .
I'm guessing it knows about this from the notice to mariners about the launch.

Is the 20 knot limit a limit on sustained wind speed or gusts?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 04:47 PM
Warning: typical weather data is obtained from anemometers located on a weather tower, at different levels.  We are directly looking at, and analyzing, anemometers located at the launch pad itself, so there WILL be a difference!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: edkyle99 on 04/21/2013 04:48 PM
Wall, all I can say is the the numbers are pretty harsh.

The 30X has a mass fraction of 7.5%  - I think even the first stage of F9 does better.  (comparing it to old DII upper stage is not a good basis for comparison, is it?)

The unit cost of the US is then going to be higher, right?

Lastly, honestly, $57M doesn't sound that cheap for development cost.

Shrug. 

The point is, after it flies, it needs to compete. 
Can't compare a first stage with a smaller upper stage.  Different animals.  And Falcon 9 is a bigger rocket in general.  But sure, a LOX/RP stage can be more mass efficient than a solid stage, but it can also cost more - maybe much more, both to develop and to fly.   How much do you think it will cost SpaceX to develop its v1.1 upper stage, which after all these years of engineering and testing has not yet flown?  Billions of dollars will have flown into this company during this time.

$57 million for a complete development program of an upper stage of this capability is cheap.  Orbital is going to probably garner close to $200 million gross income per COTS mission, roughly speaking.  If Antares flies 57 times, which is plausible, that development cost would amortize to $1 million per launch, but even less than that if inflation is considered.         

 - Ed Kyle
Title: Re: Antares A-One General Discussion Thread (2)
Post by: meekGee on 04/21/2013 05:35 PM
Wall, all I can say is the the numbers are pretty harsh.

The 30X has a mass fraction of 7.5%  - I think even the first stage of F9 does better.  (comparing it to old DII upper stage is not a good basis for comparison, is it?)

The unit cost of the US is then going to be higher, right?

Lastly, honestly, $57M doesn't sound that cheap for development cost.

Shrug. 

The point is, after it flies, it needs to compete. 
Can't compare a first stage with a smaller upper stage.  Different animals.  And Falcon 9 is a bigger rocket in general.  But sure, a LOX/RP stage can be more mass efficient than a solid stage, but it can also cost more - maybe much more, both to develop and to fly.   How much do you think it will cost SpaceX to develop its v1.1 upper stage, which after all these years of engineering and testing has not yet flown?  Billions of dollars will have flown into this company during this time.

$57 million for a complete development program of an upper stage of this capability is cheap.  Orbital is going to probably garner close to $200 million gross income per COTS mission, roughly speaking.  If Antares flies 57 times, which is plausible, that development cost would amortize to $1 million per launch, but even less than that if inflation is considered.         

 - Ed Kyle

Wait - the entire F9, including engines, was about $300M, wasn't it?

And the US for the 1.1 is currently getting assembled onto it.

So when you say "which after all these years of engineering and testing has not yet flown" - are you referring to the Raptor engine? Because that's a foundation for an entire new set of rockets, and there's absolutely no indication it ate "Billions of Dollars", or that it has even been tested.

Or are you referring to the 1.1 ?  Since it hasn't exactly been "all these years of engineering and testing" - it's a pretty quick follow-on to the F9 1.0, with quite an enhanced set of capabilities.

But back to the solid, and irrespective of F9, it's not like ATK had to develop new fuel, or new casing, or new nozzle or actuation or avionics, or invest in facilities - they already make/have all this stuff.  So I'm saying $57M seems awfully rich, and I'm not sure the unit cost of the C30L will be any lower than a liquid U/S.


Title: Re: Antares A-One General Discussion Thread (2)
Post by: clongton on 04/21/2013 05:47 PM
Why is it counting up instead of down?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: yg1968 on 04/21/2013 05:49 PM
Why is it counting up instead of down?

The clock on the live webcast is a universal time clock.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/21/2013 06:36 PM
From OSC's Twitter account:

Quote
Orbital Sciences ‏@OrbitalSciences
Even though it will consume close to 1ton of prop every second after lift-off, the early acceleration will be surprisingly slow.

Quote
Orbital Sciences ‏@OrbitalSciences
When the engines first ignite, the rocket will not lift off from the pad for two full seconds.

Quote
Orbital Sciences ‏@OrbitalSciences
At 10 seconds after Stage 1 engine ignition the vehicle will have accelerated to about 40 mph and climbed to 230 feet altitude.

Quote
Orbital Sciences ‏@OrbitalSciences
At 20 seconds after ignition, #Antares will be traveling at 100 mph at be about 1,250 feet above the pad.

Quote
Orbital Sciences ‏@OrbitalSciences
Even after 60 seconds, the vehicle will still be subsonic (about 460 mph) at just over 3 miles in altitude. #Antares

Quote
Orbital Sciences ‏@OrbitalSciences
#Antares achieves Mach 1 about 75 seconds after lift-off, when it will be at about 30,000 feet in altitude.

Do we got a winner for the smallest T/W ratio of all rockets currently used? From Ed Kyle's data I got T/W= ~1.1 (!) (comparison: Saturn V is around 1.2 and the Atlas V 401 is ~1.28)  :o
Title: Re: Antares A-One General Discussion Thread (2)
Post by: yg1968 on 04/21/2013 06:42 PM
upstream just went offline for me too

It's now back online. It's been going on and off line for a while.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 06:44 PM
Actually, the liftoff to 20 seconds data is surprisingly close to the Apollo 11 Saturn V numbers.  Then the Saturn V looses mass percentage faster than Antares due to the 3 stages vs. Antares only 2, then when S-V staged Antares outaccelerates S-V and the two trade acceleration leads through the rest of the staging sequence (remember, Saturn V stage 3 Earth Orbit MECO was about mid-depletion...)

DWT said that, if asked, he'll say that the Antares climb-out is "majestic" ...  :D
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ugordan on 04/21/2013 06:50 PM
Actually, the liftoff to 20 seconds data is surprisingly close to the Apollo 11 Saturn V numbers.  Then the Saturn V looses mass percentage faster than Antares due to the 3 stages vs. Antares only

I thought Saturn V losing more mass % after 20 sec (but still during 1st stage!) would be due to lower Isp of F-1 vs. AJ-26?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 06:55 PM
That, too.  But Antares' stage 1 is also larger in total percentage than S-V's stage 1 so it gets "depleted" slower w.r.t. the total mass of the rocket (stage 1 provides more of the total DV in Antares' case than S-V)

To tell you the thruth, I haven't run the numbers, so I don't know which effect is greater...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: yg1968 on 04/21/2013 06:57 PM
Quote
[Question:] What wind speeds are considered too high for launch?

[Answer from Orbital:] Ground winds consistently above 20 knots (23 mph).

https://twitter.com/OrbitalSciences/status/326043289264459777
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Chris Bergin on 04/21/2013 07:00 PM
Since there has been some confusion about how the winds affected our launch attempts and who has authority to wave what, I'd like to offer the following (admittedly a bit pedestrian) explanation:

Surface winds AT THE PAD affect the clearance during lift-off.  Orbital has established a basic 15kts limit for ANY DIRECTION, waivable to 20kts by LD (Eberly).  Eberly has a "pocket reserve" of a few kts if the wind direction is "away from the TEL."  The range helps LD with the go/nogo decision (including computing its effect on POV) but this is not a range decision - it's Orbital's.

Wind SHEAR during ascent induces an angle of attack that changes the aerodynamic load on the vehicle.  This being a first flight, we (Orbital) have rather strict limits on this, which can be alleviated by the choice of trajectory (out of about 5 pre-loaded in the Flight Computer) which can be made as late as L-45m.  Range sends us (Paul Baumgartner and Tracy Chisholm) the balloon data and they (Paul and Tracy) compute the resulting aero loads right at their consoles in the RCC.  Again, an Orbital call - no "single" wind speed limit value.  Not counted on the Weather Officer's POV forecast.

Wind magnitude and direction affect the ground track of trajectory which could bring the vehicle closer to a destruct line than we would be comfortable with.  The trajectories (out of the five mentioned above) that relief aerodynamic loads tend also to be "looser" in terms of lateral position tightness... so, for example, yesterday, only ONE of the trajectories met the aero load criteria (again, yesterday was a 4-sigma day as far as altitude winds were concerned) and that trajectory "grazed" the north destruct line close to the pad.  Again, this is an Orbital call, and Saturday we were ready to fly with that trajectory and those winds (having discussed the trajectory with the FSO who was OK with the grazing.)  Not in the POV.

Now for the part which is NOT under Orbital's discretion: winds and clouds affect three "Public Safety" criteria: Distance Focusing Overpressure (DFO), Toxicity, and Debris.  I don't know a lot about DFO - I believe it is associated with being indoors and a blast breaking the windows and the glass injuring the public.  Toxicity is associated with things such as nitrogen tetroxide, hydrazine and - gulp - plutonium.  We don't have any of these nasty items on THIS flight (Cygnus WILL carry Hydrazine and N2O4.)  Debris is simply pieces of a (supposedly destroyed) rocket falling on undesirable places and is affected by, among other things, population density.

Both the ranges AND the FAA have a "probability of casualty (E sub C)" calculation protocol that is driven by the size and characteristics of the vehicle, the geography of the trajectory, and the atmosphere (winds, clouds, temperature profile, etc.)  The range recalculates these probabilities whenever they launch a balloon.

All U.S. ranges agreed to add up the E sub C of each effect and use a composite criterion (100 per million) as a range go/no go criterion.  FAA on the other hand (I will not comment on why) requires each of the three to be under 30 ppm.  Therefore, you could be OK with the range E sub C but not with the FAA's, as happened on Wednesday (DFO was higher than 30 ppm, toxicity is zero for this vehicle, debris was under 30 ppm) - the composite was well below 100 ppm, so the range was OK, but the DFO was above 30 ppm, so FAA was NOT OK.

In addition, the range can - and does - impose a "no debris expected to fall" area in the VICINITY OF THE RANGE - and the FAA automatically "imposes" the same rule.  There are no "probabilities" in this calculation: it is a "binary" criterion.  Balloon data also drives this calculation.

THIS ONE is what stopped us yesterday: Wallops was willing to do a real-time redraw of the affected area (the souther tip of Assateague Island) that the strong mid-altitude winds created, with the necessary evacuation of the public (some 40 people according to the Fish and Wildlife people that control that area), but FAA was unable to concur in real time.

None of these criteria can be part of the POV since they depend on the complex atmospheric profile that is much, much harder to forecast than, say, surface winds or cloud bases.

I hope this clarifies a bit what is admittedly a very complex situation.

As others have noted, that's really informative. Thanks for taking the time to write that up!
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mtakala24 on 04/21/2013 07:01 PM
What kind of tracking cameras does the range have? Do we get to see footage on NasaTV?

Or will it be similar to Soyuz launches, where the tracking footage is only rarely seen and NASATV only shows normal tv camera footage.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 07:08 PM
The range has an amazing range (no pun intended) of cameras, including some high-speed devices on loan from JSC (yes, JSC)  Obviously, there is a much more limited choice for real-time casting.  I don't know what the public availability of the other material will be, it will not belong to Orbital.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: deltaV on 04/21/2013 07:17 PM
That, too.  But Antares' stage 1 is also larger in total percentage than S-V's stage 1 so it gets "depleted" slower w.r.t. the total mass of the rocket (stage 1 provides more of the total DV in Antares' case than S-V)

To tell you the thruth, I haven't run the numbers, so I don't know which effect is greater...

IANARS but I don't think that number of stages affects acceleration before staging occurs. Assuming that two rockets have the same specific impulse and same initial thrust to weight ratio it follows that they have the same acceleration vs. time curve (before staging).

The specific impulse effect is real. Another reason for the Saturn V to pull ahead during the later part of the first stage burn is that the F1 has more back-pressure losses at sea level than the RD-180 so its thrust increases more as its ascends than RD-180 does.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 07:38 PM
Right now, my brain is too fried to think...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Space Pete on 04/21/2013 07:56 PM
Still lots of aircraft in the vicinity of Wallops - I assume airspace will be closed for launch?

http://flightaware.com/live/airport/KWAL
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 08:09 PM
Those are probably mission aircraft
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/21/2013 08:12 PM
No, they are not... I don't know when the NOTAMS activate ...
Title: Re: Antares A-One General Discussion Thread (2)
Post by: sdsds on 04/21/2013 08:38 PM
Is it simply an effect of shadowing or is the upper part of the yellow duct now a darker color than the rest?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ugordan on 04/21/2013 08:39 PM
Shadow.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mtakala24 on 04/21/2013 08:40 PM
Shadow of the water tower.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ClaytonBirchenough on 04/21/2013 08:49 PM
Dumb question, but I'm curious... What's the orbital decay on the mass simulator?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kaputnik on 04/21/2013 08:50 PM
Dumb question, but I'm curious... What's the orbital decay on the mass simulator?

About 2 weeks.
And please don't post questions on the live update thread, Chris is busy enough as it is  :)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: yg1968 on 04/21/2013 08:54 PM
Next poll for final count is at L-12 mins.

We missed it because NASA TV decided to show a video instead. Grrr... They should start their webcast 30 minutes earlier in order to show their videos.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/21/2013 09:52 PM
Dumb question, but I'm curious... What's the orbital decay on the mass simulator?

They said about 2 weeks on the NASA TV broadcast.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mtakala24 on 04/21/2013 11:37 PM
having watched the liftoff replay a few times, it seems that the stage really did not move too much towards the TEL, but right after that, seemed to move quite a way to the opposite side, which makes it look like it did move towards the TEL. And I have a strong feeling that this movement away from it was by design.

Of course, I'm just an amateur.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: antonioe on 04/22/2013 04:32 AM
What you saw MIGHT be the "Baumgartner Maneuver" - an initial pitch AWAY from the TEL makes the TAIL of the rocket actually get CLOSER to the TEL ... but then the resulting (small) lateral acceleration carries the rocket AWAY from it ... this maneuver had to be very carefully designed, a trade between the initial tail movement towards the obstacle which is the inevitable result of the pitch, and the desired effect...

I was told (by Paul B. himself) that the pitch-away and the resulting tail-towards-TEL motion would be so small that they would not be perceptible ... maybe he was not counting on telephoto lenses and HD video (and sharp NASASpaceflight subscribers...)  ;D
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Retired Downrange on 04/22/2013 04:38 AM
...and I think they could use some more of that high velocity tape to hold the umbilical segments to the TEL :)

edit-spelling
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Kabloona on 04/22/2013 04:42 AM
What you saw MIGHT be the "Baumgartner Maneuver" - an initial pitch AWAY from the TEL makes the TAIL of the rocket actually get CLOSER to the TEL ... but then the resulting (small) lateral acceleration carries the rocket AWAY from it ... this maneuver had to be very carefully designed, a trade between the initial tail movement towards the obstacle which is the inevitable result of the pitch, and the desired effect...


You might want to consider replacing the Baumgartner Maneuver with the Fly Straight Up Maneuver... ;)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: aameise9 on 04/22/2013 07:47 AM
The Economist (typically lukewarm on space) covers Antares launch:

http://www.economist.com/blogs/babbage/2013/04/private-spaceflight (http://www.economist.com/blogs/babbage/2013/04/private-spaceflight)
Title: Re: Antares A-One General Discussion Thread (2)
Post by: mlindner on 04/22/2013 08:03 AM
The Economist (typically lukewarm on space) covers Antares launch:

http://www.economist.com/blogs/babbage/2013/04/private-spaceflight (http://www.economist.com/blogs/babbage/2013/04/private-spaceflight)

Orbital is publicly traded. They're lukewarm on space because space doesn't interest public investors usually.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ugordan on 04/22/2013 08:49 AM
What was the purpose of the slow roll that lasted for much of the 1st stage burn?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/22/2013 09:52 AM
Interesting old documentary about the strange history of the NK-15/33 (and also the RD-180!): http://forum.nasaspaceflight.com/index.php?topic=31715.0 (http://forum.nasaspaceflight.com/index.php?topic=31715.0)

What was the purpose of the slow roll that lasted for much of the 1st stage burn?

Are you sure that is intentional?  ???
Title: Re: Antares A-One General Discussion Thread (2)
Post by: ugordan on 04/22/2013 10:22 AM
It was a constant, slow rate that stopped a while before staging so yes, I think it was intentional.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Mapperuo on 04/22/2013 10:44 AM
Whats the big object on the scissor lift in this photo:

http://www.flickr.com/photos/nasahqphoto/8670672096/in/photostream
Title: Re: Antares A-One General Discussion Thread (2)
Post by: renclod on 04/22/2013 10:48 AM
What was the purpose of the slow roll that lasted for much of the 1st stage burn?

It may be keeping an antenna pointing a certain way.


Title: Re: Antares A-One General Discussion Thread (2)
Post by: plank on 04/22/2013 11:13 AM
Was yesterday nominal enough for everyone?   :D
Title: Re: Antares A-One General Discussion Thread (2)
Post by: renclod on 04/22/2013 11:18 AM
Whats the big object on the scissor lift in this photo:

http://www.flickr.com/photos/nasahqphoto/8670672096/in/photostream

Could be accoustics capture equipment, microphones.

Title: Re: Antares A-One General Discussion Thread (2)
Post by: robertross on 04/22/2013 11:46 AM
What you saw MIGHT be the "Baumgartner Maneuver" - an initial pitch AWAY from the TEL makes the TAIL of the rocket actually get CLOSER to the TEL ... but then the resulting (small) lateral acceleration carries the rocket AWAY from it ... this maneuver had to be very carefully designed, a trade between the initial tail movement towards the obstacle which is the inevitable result of the pitch, and the desired effect...

I was told (by Paul B. himself) that the pitch-away and the resulting tail-towards-TEL motion would be so small that they would not be perceptible ... maybe he was not counting on telephoto lenses and HD video (and sharp NASASpaceflight subscribers...)  ;D

That explains what I saw...though it certainly came mighty close.

Thanks Antonioe.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: plank on 04/22/2013 01:17 PM
edit nvm.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: CardBoardBoxProcessor on 04/22/2013 01:48 PM
Slightly off topic. but Is a modified Antares going to be used for the the Stratolaunch rocket?

also, will the mass simulator ever deorbit? Or is it up there forever?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 04/22/2013 01:53 PM
Slightly off topic. but Is a modified Antares going to be used for the the Stratolaunch rocket?


Not known at this moment - though our common wisdom is that it probably isn't - it may have solid lower stages.

also, will the mass simulator ever deorbit? Or is it up there forever?

The orbit is quite low (~250 km altitude) such that all objects from this launch should decay within a few weeks.
Title: Re: Antares A-One General Discussion Thread (2)
Post by: catdlr on 04/22/2013 06:40 PM
April 22, 2013
 
RELEASE : 13-107
 
 
NASA Successfully Launches Three Smartphone Satellites
 
 
WASHINGTON -- Three smartphones destined to become low-cost satellites rode to space Sunday aboard the maiden flight of Orbital Science Corp.'s Antares rocket from NASA's Wallops Island Flight Facility in Virginia.

The trio of "PhoneSats" is operating in orbit, and may prove to be the lowest-cost satellites ever flown in space. The goal of NASA's PhoneSat mission is to determine whether a consumer-grade smartphone can be used as the main flight avionics of a capable, yet very inexpensive, satellite.

Transmissions from all three PhoneSats have been received at multiple ground stations on Earth, indicating they are operating normally. The PhoneSat team at the Ames Research Center in Moffett Field, Calif., will continue to monitor the satellites in the coming days. The satellites are expected to remain in orbit for as long as two weeks.

"It's always great to see a space technology mission make it to orbit -- the high frontier is the ultimate testing ground for new and innovative space technologies of the future," said Michael Gazarik, NASA's associate administrator for space technology in Washington.

"Smartphones offer a wealth of potential capabilities for flying small, low-cost, powerful satellites for atmospheric or Earth science, communications, or other space-born applications. They also may open space to a whole new generation of commercial, academic and citizen-space users."

Satellites consisting mainly of the smartphones will send information about their health via radio back to Earth in an effort to demonstrate they can work as satellites in space. The spacecraft also will attempt to take pictures of Earth using their cameras. Amateur radio operators around the world can participate in the mission by monitoring transmissions and retrieving image data from the three satellites. Large images will be transmitted in small chunks and will be reconstructed through a distributed ground station network. More information can found at:
 

http://www.phonesat.org


NASA's off-the-shelf PhoneSats already have many of the systems needed for a satellite, including fast processors, versatile operating systems, multiple miniature sensors, high-resolution cameras, GPS receivers and several radios.

NASA engineers kept the total cost of the components for the three prototype satellites in the PhoneSat project between $3,500 and $7,000 by using primarily commercial hardware and keeping the design and mission objectives to a minimum. The hardware for this mission is the Google-HTC Nexus One smartphone running the Android operating system.

NASA added items a satellite needs that the smartphones do not have -- a larger, external lithium-ion battery bank and a more powerful radio for messages it sends from space. The smartphone's ability to send and receive calls and text messages has been disabled.
Each smartphone is housed in a standard cubesat structure, measuring about 4 inches square. The smartphone acts as the satellite's onboard computer. Its sensors are used for attitude determination and its camera for Earth observation.

For more about information about NASA's Small Spacecraft Technology Program and the PhoneSat mission, visit:

http://www.nasa.gov/smallsats


The PhoneSat mission is a technology demonstration project developed through the agency's Small Spacecraft Technology Program, part of NASA's Space Technology Mission Directorate. The directorate is innovating, developing, testing and flying hardware for use in future science and exploration missions. NASA's technology investments provide cutting-edge solutions for our nation's future. For more information about NASA's Space Technology Mission Directorate, visit:
 

http://www.nasa.gov/spacetech


 
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Title: Re: Antares A-One General Discussion Thread (2)
Post by: Galactic Penguin SST on 05/03/2013 03:09 AM
One question about the heat shield on the AJ-26 engines: previously we have seen photos of the heat shield being pink in color during the roll-out. Can anyone confirm if that is a layer removed before launch or not? If so, what color are the heat shields of during launch?
Title: Re: Antares A-One General Discussion Thread (2)
Post by: Mapperuo on 05/03/2013 06:36 AM
One question about the heat shield on the AJ-26 engines: previously we have seen photos of the heat shield being pink in color during the roll-out. Can anyone confirm if that is a layer removed before launch or not? If so, what color are the heat shields of during launch?

They are visible on one of three videos of launch in the L2 section. Still attached and pinkish.