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

[Hankelow8]

Good to see SpaceX Youtube Technical webcast is back up

[kevin-rf]

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

TKS

[sewebster]

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

Gemini 2?

Both its flights were suborbital.

Russian?

https://en.wikipedia.org/wiki/VA_spacecraft

(and I assume you include orbital only, otherwise Blue Origin, right? or did they only reuse the booster)

[envy887]

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.

That is 15 orbits later, not just 1. The orbit passing over Florida reaches its southernmost point around the longitude of New Zealand. The orbit after that is shifted ~1000 miles west and reaches its southernmost latitude near Tasmania.

The hazard area shows an orbit with it's southernmost point ~1000 miles EAST of New Zealand. That's the orbit BEFORE passing over Florida... or 15 orbits (22.5 hours) later.

[Oersted]

CRS-11 patch with four stars in the sky and CRS-4 patch with eleven stars in the sky... - What witchcraft is this?

[Lars-J]

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

That would make sense, since we were told that this and the next flight would be back to the slower propellant load, so this might be the last two "block 3" stages.

[kevinstout]

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

Thanks for this!   Will try to catch it all in Mainz, but a few minutes earlier and with a mark 1 eyeball.


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[Skyrocket]

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

Gemini 2?

Both its flights were suborbital.

Russian?

https://en.wikipedia.org/wiki/VA_spacecraft

(and I assume you include orbital only, otherwise Blue Origin, right? or did they only reuse the booster)

Since the 1980ies, the reentry capsules of the soviet Zenit (modified Vostok) reconnaissance satellites were reused. Reportedly they were usually flown three times, sometimes four.

[ZachF]

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

That would make sense, since we were told that this and the next flight would be back to the slower propellant load, so this might be the last two "block 3" stages.

Not as much performance required on this launch either

[JimO]

Re the projected stage-2 reentry point -- what would be the point of the deorbit burn for that impact point, and when, and will it be under ground twilight conditions that can create awesome spectacle in the sky for startled observers?

[Semmel]

.... At least for the first two passes, Dragon should be easily visible.

Thanks for this!   Will try to catch it all in Mainz, but a few minutes earlier and with a mark 1 eyeball.

I have gone a bit ahead of my self.. the first two passes are with quite some sunlight still. During the first, the sun is still up and the second has significant twilight.. not sure if dragon will stand out. :/

[kevinstout]

.... At least for the first two passes, Dragon should be easily visible.

Thanks for this!   Will try to catch it all in Mainz, but a few minutes earlier and with a mark 1 eyeball.

I have gone a bit ahead of my self.. the first two passes are with quite some sunlight still. During the first, the sun is still up and the second has significant twilight.. not sure if dragon will stand out. :/

Just caught ISS at 22:58.  Was brilliant.  Let's see if the weather clears for launch...


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[Targeteer]

Why 48 hours?

[JimO]

Does anybody have the planned Stage-2 disposal burn time? If I interpret the hazard chart correctly there may be pre-dawn observation opportunities from SE Australia.

[Lar]

Better safe than sorry, even if there was general clearing, if there was a strike within 10 nm, done for today.

[kevinstout]

.... At least for the first two passes, Dragon should be easily visible.

Thanks for this!   Will try to catch it all in Mainz, but a few minutes earlier and with a mark 1 eyeball.

I have gone a bit ahead of my self.. the first two passes are with quite some sunlight still. During the first, the sun is still up and the second has significant twilight.. not sure if dragon will stand out. :/

Just caught ISS at 22:58.  Was brilliant.  Let's see if the weather clears for launch...


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Mist.  Well, will be camping in Bad Kreuznach Saturday, I guess the launch will track 10mins ahead of the transit at 24:28, which is only marginally viewable.  Might just catch it. Worth a try. 


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[toruonu]

I know it's been discussed many times that the launch window is instantaneous because considering F9 performance it doesn't have enough for a significant delay that would allow a scrub. However considering todays situation where the all go weather clearance would be <5 min after the current T-0 or for example if the lightning strike had been T-29:40 or similar they could reset to a few minute delay.

Considering that calculated F9 capabilities with the Block IV and what we guess as Block V could an F9 have a non-inst window for an ISS supply and if so by how much? Could it be enough for a 2-3 minute change i.e. todays situation or not?

[Paul_G]

Need to prep and load new mice?

[kaa]

The 48-hour turnaround is because an experiment in the Dragon requires a cold pack changed out.

[Sam Ho]

I know it's been discussed many times that the launch window is instantaneous because considering F9 performance it doesn't have enough for a significant delay that would allow a scrub. However considering todays situation where the all go weather clearance would be <5 min after the current T-0 or for example if the lightning strike had been T-29:40 or similar they could reset to a few minute delay.

Considering that calculated F9 capabilities with the Block IV and what we guess as Block V could an F9 have a non-inst window for an ISS supply and if so by how much? Could it be enough for a 2-3 minute change i.e. todays situation or not?

The payload penalty for a non-instantaneous launch window isn't all that large.  Atlas V routinely uses a 30 minute window with Cygnus.  The issue is that the flight software has to be designed to support loading a (or at least selecting a preloaded) yaw steering profile at the last minute.