SpaceX Falcon 9 : CRS-11 : June 3, 2017 : DISCUSSION

[abaddon]

At some point, launching a rocket will not be that much different from a departing plane and airlines don't do webcasts for every plane, after all.

Not in our lifetimes.  Estimates vary, but most seem to show an average of around 100,000 flights a day.  Compare that to the current ~100 flights a year and you have a difference of roughly six orders of magnitude.

I think we'll continue to see webcasts for a while, although I could see if and when CommX flights are going at the hoped-for rate they might drop those flights.  With external customers I expect we'll see webcasts well into the future.

[ChrisGebhardt]

The SpaceX #CRS-11 mission patch is a nice nod to CRS-4 patch, the mission that first flew this Dragon capsule. ♻

https://twitter.com/payloadwrangler/status/870244871638044673

Not only that, but note the coincidence of the CRS-4 patch having 11 stars... a nice unintended prediction to reuse on CRS-11.

[tvg98]

The SpaceX #CRS-11 mission patch is a nice nod to CRS-4 patch, the mission that first flew this Dragon capsule. ♻

https://twitter.com/payloadwrangler/status/870244871638044673

Not only that, but note the coincidence of the CRS-4 patch having 11 stars... a nice unintended prediction to reuse on CRS-11.

So it is unintentional? I always thought they already had decided when to reuse the first Dragon years ago.

[ChrisGebhardt]

The SpaceX #CRS-11 mission patch is a nice nod to CRS-4 patch, the mission that first flew this Dragon capsule. ♻

https://twitter.com/payloadwrangler/status/870244871638044673

Not only that, but note the coincidence of the CRS-4 patch having 11 stars... a nice unintended prediction to reuse on CRS-11.

So it is unintentional? I always thought they already had decided when to reuse the first Dragon years ago.

I don't believe in 2014 they knew which mission would be first to reuse a capsule - let alone which capsule would be first.  I could be wrong, but I don't recall CRS-11 being official for first capsule reuse until last year.

[JasonAW3]

SpaceX looks like it is continuing its testing of extended loiter time for upper stages.  Compare 2nd stage disposal areas of previous CRS missions vs. CRS-11 (from Raul's maps).  Looks like it is being done at least 1 orbit later.

No, that looks like a deorbit just 10 to 15 minutes later.

That almost looks like they have a vision of ROA (recovery once around) for the 2nd stage in the future - increase the loiter times more and more to achieve a reentry closer to the Cape in the end .

One can dream, right?

Quick question; what's the minimum speed that the 2nd stage be brought down to before it would start it's descent into the thicker atmosphere?  I'm assuming a semi-circularized orbit could be achieved at the upper fringes of the atmosphere.

     Would it be possible to allow it to use passive, low heat, aerobraking, (skimming off of the highest part of the atmosphere) to kill as much velocity as possible prior to reentry?

     As it is unmanned, the only rush that I could see to bring it back down is battery duration and cryo limitations.

[tvg98]

The SpaceX #CRS-11 mission patch is a nice nod to CRS-4 patch, the mission that first flew this Dragon capsule. ♻

https://twitter.com/payloadwrangler/status/870244871638044673

Not only that, but note the coincidence of the CRS-4 patch having 11 stars... a nice unintended prediction to reuse on CRS-11.

So it is unintentional? I always thought they already had decided when to reuse the first Dragon years ago.

I don't believe in 2014 they knew which mission would be first to reuse a capsule - let alone which capsule would be first.  I could be wrong, but I don't recall CRS-11 being official for first capsule reuse until last year.

Just double checked, seems that you are right. Quite the coincidence indeed.

[freda]

I saw the post and photo by FutureSpaceTourist in the Updates thread.  http://forum.nasaspaceflight.com/index.php?topic=42972.msg1685044#msg1685044
By coincidence, the "Go Up" forum menu was right near the photo of Falcon pointing up!  Screen image attached.  Just thought that looked fun. :-)

[Semmel]

Here in Berlin/Germany, we have some weeks of fantastic weather and I have seen the ISS almost every day for multiple passes. Orbital timing with the day/night boundary are fantastic right now. I assume I can catch the dragon as well tomorrow evening. Any idea how far away it will be from ISS? Better yet, is there information on the distance of ISS to dragon vs. time after launch?

And is there an estimation how bright it might be? If its darker than mag 5, I have probably no chance of finding it because the sky is bright in Berlin.

To answer my own question: Dragon will be ~10 minutes ahead of the ISS at launch in a lower orbit and will slowly get ahead of ISS before coming in from behind two days later. So best viewing options for northern Germany will actually be Saturday evening where there are 3 visible ISS passes short before berthing. For Berlin in local time, there are three bright passes:
19:42 (17:42 UTC)
21:18 (19:18 UTC)
22:55 (20:55 UTC)
Berthing of dragon is planned to be 23:07 local (21:07 UTC) in Berlin on Saturday.

I dont have gear to take photos of this, but I will watch with my Pentax 20x60 Binocular.. which has a resolution of under 10 arc seconds. At least for the first two passes, Dragon should be easily visible.


@edit:
Thx to  https://www.reddit.com/r/spacex/comments/6cyjjo/heads_up_on_possible_rare_visible_pass_of_crs11/?sort=new
and http://www.spacex.com/sites/spacex/files/crs11presskit.pdf

[NX-0]

I never figured why there were 2 different webcasts (hosted and technical) anyway. To me it sounded like too much effort for just us space geeks and thus not worth it.

I loved the technical webcasts. There were no talking heads getting in the way of SpaceX mission control.

Same. But we are a pretty narrow audience, maybe most people love talking heads (they ARE easy on the eyes). On the other hand, presumably it was lower cost to create (no studio, just feeds). And on the gripping hand, I'm just happy for what they give us. I'll be watching with rapt attention as always... and I have my new SpaceX shirt on today.

Consider the Stanley Cup or World Series (and especially, the Olympics).
Every story line or rule that fans are familiar with over the course of the season gets repeated for the casual fan that just tunes in for the playoffs.
I noticed on the shuttle flight coverage that they kept repeating the same old factoids.
(SpaceflightNow's live coverage, they only change the dates and numbers, I think, for instance.)

[Kaputnik]

SpaceX looks like it is continuing its testing of extended loiter time for upper stages.  Compare 2nd stage disposal areas of previous CRS missions vs. CRS-11 (from Raul's maps).  Looks like it is being done at least 1 orbit later.

No, that looks like a deorbit just 10 to 15 minutes later.

That almost looks like they have a vision of ROA (recovery once around) for the 2nd stage in the future - increase the loiter times more and more to achieve a reentry closer to the Cape in the end .

One can dream, right?

Quick question; what's the minimum speed that the 2nd stage be brought down to before it would start it's descent into the thicker atmosphere?  I'm assuming a semi-circularized orbit could be achieved at the upper fringes of the atmosphere.

     Would it be possible to allow it to use passive, low heat, aerobraking, (skimming off of the highest part of the atmosphere) to kill as much velocity as possible prior to reentry?

     As it is unmanned, the only rush that I could see to bring it back down is battery duration and cryo limitations.

There are probably better threads to discuss this, but in general a low orbit will tend to self circularise, because the drag at perigee lowers the apogee. Spiralling down to the lowest possible orbit will happen naturally, but you will risk entry at a random point, and the reduction in orbital energy is insignificant, in terms of vehicle survival.

[S.Paulissen]

How are high altitude winds looking? They always seem to be in the mix for scrubs.

[John Santos]

SpaceX looks like it is continuing its testing of extended loiter time for upper stages.  Compare 2nd stage disposal areas of previous CRS missions vs. CRS-11 (from Raul's maps).  Looks like it is being done at least 1 orbit later.

No, that looks like a deorbit just 10 to 15 minutes later.

That almost looks like they have a vision of ROA (recovery once around) for the 2nd stage in the future - increase the loiter times more and more to achieve a reentry closer to the Cape in the end .

One can dream, right?

Quick question; what's the minimum speed that the 2nd stage be brought down to before it would start it's descent into the thicker atmosphere?  I'm assuming a semi-circularized orbit could be achieved at the upper fringes of the atmosphere.

     Would it be possible to allow it to use passive, low heat, aerobraking, (skimming off of the highest part of the atmosphere) to kill as much velocity as possible prior to reentry?

     As it is unmanned, the only rush that I could see to bring it back down is battery duration and cryo limitations.

Channeling Jim: No.

Long Answer: The slowest possible velocity it could achieve through aerobraking without re-entering immediately (i.e. within the next half orbit) would be the lowest possible circular orbit (at about 150km, or about 90 miles) where the air is thin enough to not cause immediate reentry.  The velocity in this orbit would actually be somewhat higher than a higher orbit (typical for LEO and less subject to decay), or about 25000 km/h (18000 mph).  Any slower and the perigee would dip far enough into the atmosphere to result in lithobraking.

Aerobraking is fine for reducing the apogee of an elliptical orbit, but useless for reentry on any planet massive enough to hold an atmosphere dense enough that aerobraking would be effective.

Edit: What Kaputnik said.

[edkyle99]

Photos seem to suggest that this Falcon 9 is back to the Block 3 second stage, after two flights by Block 4 second stages.

 - Ed Kyle

[Bargemanos]

Photos seem to suggest that this Falcon 9 is back to the Block 3 second stage, after two flights by Block 4 second stages.

 - Ed Kyle

Is there an image of a comparison?

[Kaputnik]

  The velocity in this orbit would actually be somewhat higher than a higher orbit.

Yes, which appears to be counterintuitive, but the energy is still lower. It's the velocity at the entry interface that matters, and if you deorbit from higher up, you will fall in and pick up speed.

[meekGee]

At some point, launching a rocket will not be that much different from a departing plane and airlines don't do webcasts for every plane, after all.

Not in our lifetimes.  Estimates vary, but most seem to show an average of around 100,000 flights a day.  Compare that to the current ~100 flights a year and you have a difference of roughly six orders of magnitude.

I think we'll continue to see webcasts for a while, although I could see if and when CommX flights are going at the hoped-for rate they might drop those flights.  With external customers I expect we'll see webcasts well into the future.

I'd point out that airplane traffic went from 100/yr to current levels within a lifetime.

So maybe not OUR lifetime, but someone's...

[Doesitfloat]

Just to confirm:
This is the first time a capsule spacecraft will be reused.

[StarTracker]

Just to confirm:
This is the first time a capsule spacecraft will be reused.

Gemini 2?

[whitelancer64]

Just to confirm:
This is the first time a capsule spacecraft will be reused.

Gemini 2?

Both its flights were suborbital.

[LucR]

Photos seem to suggest that this Falcon 9 is back to the Block 3 second stage, after two flights by Block 4 second stages.

In the pre-launch presser, Hans noted in response to a question about the faster LOX load that this requires specific hardware on the stage that isn't there for the current launch and the next one, but will be there for all subsequent launches. So that corroborates your block 3 / block 4 second stage deduction.