Space Shuttle Ultra Are there any tutorials on how to deorbit?

Snax

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Hello, are you familiar with the spaceflight in Orbiter and the Space Shuttle in general, or you entirely new ?
If you are not new, I can suggest two MFDs to help yo to do that (GlideSlopeMFD & BaseSyncMFD, they need ModuleMessagingExt to work together). They are pretty easy to understand and use.

If you are new, do you know the basics of reentry with a spaceplane like the Shuttle (or any other spaceplane, Buran, the X-37B, etc) ?
If so have you tried with a vessel like the default DeltaGlider, the addon Ravenstar/Vanguard ?
I can suggest you this video as a start that explain the principles of reentry for the Space Shuttle (or any other spaceplane).

Then next, my oher question is, as assuming you are on Orbiter 2016, are you using the default Space Shuttle coming with Orbiter 2016 or an addon like STS2016, Space Shuttle Vessel ?
Depending on the vessel you use, the method will be slightly different.

PS: After having watched the aforementioned video, you can to see in practice how it goes during a reentry (manually done) in Orbiter 2016 using GlideslopeMFD, this is how it looks in a timelapse. This is the general idea of how a reentry will look like with a spaceplane (after the deorbit burn of course).
 

jamest

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Hi, I have a general idea of how the shuttle re-enters but I'm not sure how to aim for the runway at the KSC. I am aware that I need to use bank angles to reduce lift, but I'm not sure when to do them and for how long.

I am using SSU for orbiter 2016 and I cant figure out how to program the shuttle to deorbit for the KSC. all the NASA checklists go over my head. I have landed the delta glider before but I had to use the main engine a few times as I was just short of the runway.

Thanks for your help
 

Urwumpe

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Hi, I have a general idea of how the shuttle re-enters but I'm not sure how to aim for the runway at the KSC. I am aware that I need to use bank angles to reduce lift, but I'm not sure when to do them and for how long.

That is something you better train first on a DG-class vessel (including DG IV and XR), if you want to fly it manually. Yes, a really stupid computer can do this. No, it requires training for human pilots, because the human brain was never designed for this task in mind.

The important library keyword to look for the theory is "energy management". That is what you do to aim for a specific runway:

  1. Until you have landed, you always have energy.
  2. If you have too much energy, you will overshoot.
  3. If you have not enough energy, you will need to add energy by using the engines (and that is perfectly fine, the fuel must not be returned after the mission)
  4. Knowing how much energy you have can be done exact by a computer, but you can also learn to estimate it good enough.
  5. Knowing how much energy you need to reach a base, is again, possible with plain experience.
  6. The trick is to keep a small bit of reserve energy to prevent undershooting, but still have not so much energy, that you can't bleed it away before final approach.
  7. That requires mostly training. (I needed 6 attempts with the Dynasoar until I finally landed at the base the first time)
  8. How much energy you bleed away, can be best controlled by taking a look at the ACC indicator in Surface MFD. Its not perfectly accurate, but the best you can get without extra MFDs.
  9. At early reentry, you have not much room for decisions to manage your energy, you have only a small corridor between burning up, breaking up and skipping out. Once you get below about Mach 10, you will only be able to steer towards the base with S-turns.
  10. Thus your deorbit has to take place at just enough distance to the base, that you have enough distance to the base left at the moment you drop below Mach 10, for managing your energy before final approach.
  11. Again: Its all a matter of training. There are MFDs around like AerobrakeMFD, that can make your life easier, but you don't need it.

I am using SSU for orbiter 2016 and I cant figure out how to program the shuttle to deorbit for the KSC. all the NASA checklists go over my head. I have landed the delta glider before but I had to use the main engine a few times as I was just short of the runway.

SSU is a completely different beast. There it is less about flying the reentry than about programming the on-board computers properly and balance the spacecraft for reentry.
 

Snax

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As @Urwumpe mentionned, SSU/SSV is a totally different beast that requires to think more like we do in a flight simulator (VC, avionics, clicky stuff) than we usually do in Orbiter (HUD, keyboard shortcut, etc).
Hi, I have a general idea of how the shuttle re-enters but I'm not sure how to aim for the runway at the KSC. I am aware that I need to use bank angles to reduce lift, but I'm not sure when to do them and for how long.

For the aiming part, I simply use the map (either the map in the MFD or the external windows with Ctrl+M to bring it as a popup) to see my predicted trajectory to keep it relatively towards my destination (KSC, EDW, etc).
In my video I've shown before (and the Shuttle for SSU) there is a "Delta Azimuth" displayed in the MFD, that indicates "heading to go". As it is automated in SSU I don't have to worry about that, however in a manual reentry with another addon for example I watch it in GlideslopeMFD and don't go further than 5° of DelAz. It usually takes 1000 nautical miles (as we use imperial units in the space shuttle and aviation, that's roughly ~1800km) to have 5° of DelAz to need to invert your bank angle for a reversal roll. And you would need to do that 4 times at least (that's how many times the Space Shuttle did it), but you can do as many as you want if needed, we just have to keep in mind that inverting your bank angle will go by 0° of bank wich means the wings are leveled and will generate lift, so we need to be quick during a reversal roll.

I am using SSU for orbiter 2016 and I cant figure out how to program the shuttle to deorbit for the KSC. all the NASA checklists go over my head. I have landed the delta glider before but I had to use the main engine a few times as I was just short of the runway.

Thanks for your help

In SSU (or SSV if you're using SSV too), before trying much and more complex stuff like a deorbit/reentry, and if you're new with SSU/SSV especially, I'd recommend to be at ease with the Shuttle's avioncs one by one with different scenarios instead of going to do all of them at once. It will be difficult and an error could cost the entire flight. Here's a diagram of the avionic's stuctrure:
1662210029333.png

Then I'd suggest to familiarize yourself with the Shuttle by "speaking Shuttle-language" with the scrachpad by playing with OPS201 (UNIV PTG) and OPS202 (ORBIT MNVR EXEC) and try to understand how all these works (and the Shuttle's terminology, you can find a lot in the Wiki the FG Space Shuttle).
Knowing this will be helpful as the logic for orbital burns is the same for a deorbit burn.
To help you with that, there are tests scenarios provided with SSU/SSV that have different stages of a mission:
  1. Deorbit
  2. Entry Interface (EI), the reentry,
  3. Terminal Area, Energy Management (TAEM), the gliding,
  4. Final/the landing
1662209454714.png
(don't mind the scenario with T-38, I added it manually for my needs)

With these you already have a Shuttle configured for the scenario so you can see what it would look like (especially for the reentry, you'll see the different stages of the reentry when everything goes to plan).

Here's OPS201 used to point the Shuttle's nose heads down in retrograde || Here's OPS202 used for orbital maneuvers (firing the OMS to change your orbit etc)
1662209641792.png1662209644679.png

Understanding these will help you greatly for OPS302/OPS303 as OPS202 displays the same informations with a bit more for reentry.

OPS302 with a deorbit burn starting from 600km of altitude and || OPS304 displaing the first stage of the reentry (ENTRY TRAJ 1) during the EI:
1662209743750.png1662209750282.png


For OPS201, I started playing with ITEM14+5 so we can enter a different attitude as desired (with ITEM15, ITEM16, ITEM17) and enter some of the values in the image below.
1662210184446.png
1662210213728.png
There's really a lot to talk and I can't make a long-ass post lol
So I'll stop here (for now) :p
Hey what if we make a "poor man's tutorial" for SSU in a PDF to have the very basics of a STS flight by detailling the different stages but keeping it simple ?
I was thinking of doing it a long time ago already and as I already used to do that for flight simulation (explaining the Airbus, Boeing, F-16 in BMS, etc).
Yeah I think I'll do that !

Anyways, have with in SSU/SSV, you'll have years of fun ahead !
 

moonheart

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Great work there - it would be very helpful to have a guided tutorial pdf to show the basics and applications of the different dps commands.
Thanks for the above!
 

thermocalc

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dear Snax,
I modesty think that your idea is a great idea...hope you manage to make some...especially on the less documented part of missions, like deorbit, orbital operations (when you need to move the arm, grabbing objcets and deploy them) as well as rendezvous and docking.
all phases where some "descriptions" on what and how to do things may shed lights....as the very good video tutorial of tim13 that in about 2h teaches how to get into orbit and do orbital adjustments ... i modesty think we would need similar detailed and descriptive tutorials for others missions parts...
i will try some easiest missions, like sts-1, now that indy91 made available the deorbit routine maybe i will manage to deorbit, if i succeed i would be more than happy to share my flight notes...but for more operations, like rendezvous, i guess i would not be able to do/describe, as still not able to do it, so i am looking forward to see some tutorials covering those mission aspects in the near future.
(I am not ashamed to say that i move from NASSP to SSV from time to time, as my frustration growth with one of them :coffee: i move to the other, when the frustration growth to the other i switch back to the other, and so forth ... but although very slowly it seems that I am going somewhere ... having similar tutorials for SSV as for NASSP would be really helpful .... but ok, time will tell :))
anyway, know that the SSU spirit is still alive and morphed into SSV i am sure there will be more information available as more users get up speeds...
all the best...and safe virtual flights/landings.
:cheers:
 
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