SpaceX Falcon 9 : Merah Putih (Telkom 4) : August 7, 2018 - DISCUSSION

[gongora]

Based on discussion at the ASAP meeting this week it isn't clear whether or not the Merlin 1D Block 5 engine design will be frozen yet.  It hasn't made it through qualification yet and may need more tweaks.

[cscott]

Based on discussion at the ASAP meeting this week it isn't clear whether or not the Merlin 1D Block 5 engine design will be frozen yet.  It hasn't made it through qualification yet and may need more tweaks.

Does qualification for SpaceX include reuse? I could imagine them wanting to validate "rapid reusability" of the block 5 engine and making tweaks until that goal is met...

[ehb]

If correct, am I right in saying that this flight wouldn't count towards the "7 flights without a significant design change" for 1st crew? It has the old pressure vessels yeah?

Correct, DM-1 will have the first locked design and start the 7 flights including in- fight abort.

Based on discussion at the ASAP meeting this week it isn't clear whether or not the Merlin 1D Block 5 engine design will be frozen yet.  It hasn't made it through qualification yet and may need more tweaks.

Does qualification for SpaceX include reuse? I could imagine them wanting to validate "rapid reusability" of the block 5 engine and making tweaks until that goal is met...

I'm reading that DM-1 may have to wait until the Merlin 1D block 5 engine can be "frozen" & they are sufficiently confident to "lock" the design.
Hopefully they are close, but it could result in delays to DM-1.

[gongora]

If correct, am I right in saying that this flight wouldn't count towards the "7 flights without a significant design change" for 1st crew? It has the old pressure vessels yeah?

Correct, DM-1 will have the first locked design and start the 7 flights including in- fight abort.

Based on discussion at the ASAP meeting this week it isn't clear whether or not the Merlin 1D Block 5 engine design will be frozen yet.  It hasn't made it through qualification yet and may need more tweaks.

Does qualification for SpaceX include reuse? I could imagine them wanting to validate "rapid reusability" of the block 5 engine and making tweaks until that goal is met...

I'm reading that DM-1 may have to wait until the Merlin 1D block 5 engine can be "frozen" & they are sufficiently confident to "lock" the design.
Hopefully they are close, but it could result in delays to DM-1.

There is more information in the Dragon 2 thread, and further discussion of the Commercial Crew stuff should move to that thread:
https://forum.nasaspaceflight.com/index.php?topic=41016.msg1842042#msg1842042

[Wolfram66]

Have we had word on causes of the leftward creep of this launch schedule? I know NET means NET, but 5 days is more than usual w/o a GSE, ASDS or booster problem

[AlphaAdhito]

Well, is this true?

https://twitter.com/EmreKelly/status/1024353070921207809?s=09
 
Seems like a further delay

[ChrisGebhardt]

Well, is this true?

https://twitter.com/EmreKelly/status/1024353070921207809?s=09
 
Seems like a further delay

The image you attached is for the 7 August attempt -- which was been reported on this thread (name change) and the main updates thread yesterday.

[envy887]

We have venting! Was taken an hour go, which is over normal load time, so it's possible a reload could have occurred.

Also note (may be because of the venting) but I can't see any soot, we sure this is B1046.2?


https://mobile.twitter.com/aWildLupiDragon/status/1025033454965145600/photo/1

The LOX tank immediately below the grid fins looks very much darker than the upper stage. At least it does to me. I think that's a sooty booster.

[Lupi]

http://www.spacex.com/sites/spacex/files/merahputihpresskit.pdf

looks like the presskit's out!

official confirmation it's the one that launched banghabangdu? check.
Anything about the whole weird static fire test where they topped it off, stood down for like an hour, and then refueled for the static fire? doen't look like it.

[ChrisC]

William Graham's feature article!
https://www.nasaspaceflight.com/2018/08/spacex-falcon-9-merah-putih-block-5-reflight/

Just wanted to say that this article is a masterpiece.  It's beautifully written, and carefully explains the entire Falcon 9 system and history.

[WindnWar]

Given the payload is 5800 kilos and they are landing the first stage again, any idea what sorta orbit we are looking at this time? Slightly subsync?

[Alexphysics]

Probably something like GTO-1900, much closer to standard than Telstar 19V

[Jakusb]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

[freda]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

Ha.  You beat me to it.  :-)  Just before I clicked to post the same question, I saw you had.
Looks like surface cleaning, probably to mount new sensors... or to re-rivet some internal structure?

[abaddon]

On previous flights, there were lines drawn in the door to check welds, but these look different.

[marsbase]

What are those markings on the middle of the core?!



Clearly a message in an alien alphabet.  Says "Take me to your leader".  I think they mean Elon.

[Herb Schaltegger]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

Ha.  You beat me to it.  :-)  Just before I clicked to post the same question, I saw you had.
Looks like surface cleaning, probably to mount new sensors... or to re-rivet some internal structure?

I rather doubt SpaceX is riveting internal components on a flown core.

Rather, I suspect those marked up areas might be places where SpaceX did some down-to-the-metal surface cleaning to enable NDT (non-destructive testing) as part of their post-flight/pre-reflight evaluations of the new Block 5 cores.

[wannamoonbase]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

Ha.  You beat me to it.  :-)  Just before I clicked to post the same question, I saw you had.
Looks like surface cleaning, probably to mount new sensors... or to re-rivet some internal structure?

I rather doubt SpaceX is riveting internal components on a flown core.

Rather, I suspect those marked up areas might be places where SpaceX did some down-to-the-metal surface cleaning to enable NDT (non-destructive testing) as part of their post-flight/pre-reflight evaluations of the new Block 5 cores.

Bingo.

That's exactly what you'd expect to see.  I bet we see the same markings in the same spot for this core until they establish data over multiple flights.

[AUricle]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

Ha.  You beat me to it.  :-)  Just before I clicked to post the same question, I saw you had.
Looks like surface cleaning, probably to mount new sensors... or to re-rivet some internal structure?

I rather doubt SpaceX is riveting internal components on a flown core.

Rather, I suspect those marked up areas might be places where SpaceX did some down-to-the-metal surface cleaning to enable NDT (non-destructive testing) as part of their post-flight/pre-reflight evaluations of the new Block 5 cores.

Bingo.

That's exactly what you'd expect to see.  I bet we see the same markings in the same spot for this core until they establish data over multiple flights.

I'm just the Messenger....Chris Bergin may have figured this out. Check his Twitter page......and look at this https://www.omniglot.com/conscripts/marain.htm

It's just such a Musk-ish thing to do .....and Elon is a big fan of Lain M Banks Culture Series

[StuffOfInterest]

SpaceX image of F9-61 on the pad.

 - Ed Kyle

What are those markings on the middle of the core?!

Someday, somebody has to write "Wash me!" with a sponge on one of those cores.