Author Topic: Starship Flight Test 3 Predictions (Read 5830 times)

dglow · « **on:** 03/11/2024 02:49 pm »

Let’s predict the outcome of Starship IFT-3!
This is a repeat of the IFT-2 poll conducted in November, the results of which were nicely summarized by @mikelepage.

Instructions
• You have 15 votes.
• Choose as many or as few options as you like.
• If you predict IFT-3 will be a perfect success, check all 15 boxes.

Remember: your votes indicate successful outcomes.
• For instance, if you think Super Heavy will perform well but won’t initiate its landing burn, check 1 through 7 and not 8 or 9.
• Similarly, if you predict Starship will begin atmospheric reentry but won’t survive the process, check 13 but neither 14 nor 15.

Enjoy!

Eer · « **Reply #1 on:** 03/11/2024 03:16 pm »

I'm optimistic - adults are in charge, they've had the chance to tweak the edges. I suspect the heat shield on the ship will work "well enough" not to burn through the steel they cover (I'm not saying they won't lose some shield tiles). I also suspect the booster sloshing will have been "managed", perhaps conservatively allowing further tweaks in the future.

rfdesigner · « **Reply #2 on:** 03/11/2024 03:36 pm »

I thinks it's reasonable to presume IFT2+

The ship will make "sub-orbit".. I appreciate the difficulty of relighting in space, but I'm sure they've figured out a way to make it work. They have a ton of experience with the F9 boost backs and landings, so we shouldn't need a dozen landings to nail the booster landing, one of the crucial aspects was how to model the engine relight times in that dynamic environment, SpaceX have also landed a ship with the flip manoeuvre using early raptors, so I think they'll have got a lot of the hard stuff figured out. Where I'm much more hesitant is with the ship re-entry. Will it remain stable.. does the shield cover enough of the ship.. will enough tiles stay attached.. how will the tanks cope with heating, I assume there'll be outgassing, but what happens to that as there'll be oxygen and methane to vent and we don't want fires.. we've never seen a ship heated.. lots of lessons to learn.

If the ship belly flops into the water in one piece, it will be remarkable. I'll be keeping my fingers crossed but I have no expectations of success beyond the beginning of reentry.

DanClemmensen · « **Reply #3 on:** 03/11/2024 04:09 pm »

No options for the three tests?
Pez door open and close
SS engine restart
Propellant transfer demonstration

dglow · « **Reply #4 on:** 03/11/2024 05:13 pm »

Quote from: DanClemmensen on 03/11/2024 04:09 pm

No options for the three tests?
Pez door open and close
SS engine restart
Propellant transfer demonstration

Keeping it like the prior one for simplicity. One could infer engine restart between Coast and Entry.

DanClemmensen · « **Reply #5 on:** 03/11/2024 05:29 pm »

Quote from: dglow on 03/11/2024 05:13 pm

Quote from: DanClemmensen on 03/11/2024 04:09 pm
No options for the three tests?
Pez door open and close
SS engine restart
Propellant transfer demonstration

Keeping it like the prior one for simplicity. One could infer engine restart between Coast and Entry.

I don't think so. The mission is specifically structured so the engine restart is not necessary. SS will hit the target re-entry area whether or not the engine restarts. (of course if engine restart results in a RUD, it will hit the target in a zillion pieces.)

litton4 · « **Reply #6 on:** 03/12/2024 09:46 am »

Quote from: DanClemmensen on 03/11/2024 05:29 pm

Quote from: dglow on 03/11/2024 05:13 pm
Quote from: DanClemmensen on 03/11/2024 04:09 pm
No options for the three tests?
Pez door open and close
SS engine restart
Propellant transfer demonstration

Keeping it like the prior one for simplicity. One could infer engine restart between Coast and Entry.
I don't think so. The mission is specifically structured so the engine restart is not necessary. SS will hit the target re-entry area whether or not the engine restarts. (of course if engine restart results in a RUD, it will hit the target in a zillion pieces.)

In the RUD case, it will tend to land shorter, since the small pieces will have a lower ballistic coeffieient.
(Those that survive that far, that is)

r8ix · « **Reply #7 on:** 03/14/2024 02:31 pm »

I picked 1-8 and 10-13. Looks like actual results were 1-7.5 or so and 10-13...

dglow · « **Reply #8 on:** 03/14/2024 03:05 pm »

Agreed. The wisdom of the crowd seems to have done pretty well. Thank you all for participating.

Two bits that intrigue:
1. Voters that appear to have chosen ‘none of the above’. A valid choice, but poor bet given past performance!
2. The vote or two that trickled in after the launch. Bad form at imitating clairvoyance – you know who you are.

Eer · « **Reply #9 on:** 03/14/2024 03:07 pm »

I’m happy to have been over optimistic. Terrific flight, great success. More data more good.

Metalskin · « **Reply #10 on:** 03/14/2024 10:10 pm »

I'm normally optimistic, but I'm surprised that I was a tad pessimistic this time. But then I only missed one, which is the booster re-entry.

Overall, I imagine SpaceX must be very happy with the results. I do hope that they got plenty of data on what was going on with the starship re-entry. I suspect that it may take a few attempts to get that sorted to be honest.