Support SSU Reentry Issue

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Hello, I've a bit of an issue with the reentry so I'm trying to get to the bottom of it and figure out what I could be doing wrong

After performing the Deorbit burn for EDW runway 15, when I switch to OPS 304, the RCS apparently positions the shuttle in preparation for the entry interface and as the nose of the shuttle reaches the horizon RCS suddenly begins rolling the shuttle endlessly to the right, and from that point on it's just an endless spin in all three axes through the atmosphere until I crash into the sea.

I'm doing the STS-1 mission, and if it's any help, here's how I did the deorbit burn (just in case my deorbit targeting was off):
Orbit is approx. 240x230km, I'm in plane with EDW and I burn precisely south of India, bleeding off 200 feet of dV which brings my periapsis down to about 30km.
Switching to OPS 304 instanly begins re-orienting the shuttle into a 90ish degree nose-down attitude, and as I get closer to the landing site and my pitch starts rising, almost as soon as it reaches 0 degrees the shuttle starts rolling to the right as every RCS thruster essentially begins firing at the same time to no end. I suppose If someone could walk me through how they do deorbits correctly I'd be able to figure out what I'm doing wrong.

Thanks
 

GLS

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Hi there!
I think you might be changing to OPS 304 a bit too soon. It should be at EI-5 minutes, and by then the nose is way up above the horizon. Otherwise you'll start the AerojetDAP and yes, it "looses its mind" with low angles of attack.
 
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Hi there!
I think you might be changing to OPS 304 a bit too soon. It should be at EI-5 minutes, and by then the nose is way up above the horizon. Otherwise you'll start the AerojetDAP and yes, it "looses its mind" with low angles of attack.

You were right!
This time around I made sure to wait until at least T-5 and I also pitched the shuttle up to about 50 degrees before switching over to OPS 304, so now it's all good. While we're at it, I'd like to ask two more questions:

1. How do I change the target landing site? Only now did I notice that STS-1 defaults to KSC runway 15 instead of Edwards.

2. What's the easiest way to calculate deorbit parameters such as TiG and dV - I always end up overshooting or undershooting the reentry envelope even though I start out nominally at the upper right corner of the envelope.

Thank you for the help! :cheers:
 

GLS

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1. How do I change the target landing site? Only now did I notice that STS-1 defaults to KSC runway 15 instead of Edwards.
SPEC 50 (HORIZ SIT) > ITEM 41+XX, where XX is the landing site number. You can find the currenty available landing sites, and their numbers, in the manual.


2. What's the easiest way to calculate deorbit parameters such as TiG and dV - I always end up overshooting or undershooting the reentry envelope even though I start out nominally at the upper right corner of the envelope.
Yeah.... we don't have that going yet... :uhh: you have to guess it somehow... :shrug:
 
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Thanks, I managed to complete STS-1 in one shot without reloads thanks to the spreadsheet and everything works as it should, of course I didn't want to leave my first successful mission undocumented so here you go! (Guidance rectangle is glitchy in the replay but it all worked like a charm during the actual landing, should've filmed it live)

 
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