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Shuttle Columbia re-entry question:

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dandypanty:
     Years ago I was watching a program on the Space Shuttle Columbia disaster when it came up that some of the NASA heads had declined an offer to use a spy satellite to image the wing while still in orbit. I cannot recall what program/documentary this was so I might be fuzzy on the details but I remember that NASA turned down the offer because even IF they saw wing damage, there was nothing they could do about it.
     It reminded me of my Titanic Blu-ray special features that features multiple experts in a variety of different fields getting together to talk about the physical evidence of "how" the Titanic went down. (EXAMPLE: did it break apart at the surface? did the back end stand straight up and bobble? etc.) The last question the filmmaker - James Cameron asks goes something like this: "If you were the captain of the ship, knowing what you know now, what would you do differently to save as many people on board as possible?" This thought experiment starts at ONE second after the iceberg is hit and the answers included some very bold decisions but very interesting. One of these ideas was immediately throwing the ship in reverse and backing up toward the ship that they saw in the distance (I believe it was called the California). One was off-loading the passengers onto the iceberg, another being filling one of the water tight compartments with all the life jackets on board and throwing mattresses over the side to block/slow the water pouring into the ship.
     A bunch of you Apollo nerds are no doubt familiar with the re-entry of the command module. It would begin it's re-entry for a period of time but then skip out to cool off, then enter the steeper slope again. I have asked this question many times in the comments of various relevant YouTube videos hoping that maybe someone much smarter than me with the proper math formulas, simulations, knowledge could help me figure out what the re-entry would look like. For the record, not a single person I have received a response from believed there was such a possibility of entering without breaking up. The answers given are unconvincing. My first thought is: using 20 - 60 of these skip outs to very slowly over the course of several days, many revolutions, very gradually entering the atmosphere. But I would like to know more definitely if that could conceivably work. If not, what would it take? What are other ideas? Which tiles are less critical that they could remove and strap to the wing? What other materials did they have to work with in the shuttle that could be strapped or attached in a way that would protect the wing (long enough) to survive?
     I understand that this theoretical isn't just about having less heat but also aerodynamics causing the thrusters to ultimately run out of fuel leading to an out of control angle of attack that caused the breakup so maybe the solution would be to fly in a constant right turn keeping as much heat away from the hole. If nobody has any ideas using what was onboard at the time, what about a re-fueling rocket that could rendezvous with the Shuttle so that the main engine/s could be used to brake and bleed off as much speed as possible before going through the thickest part of the atmosphere?
    What would it take?
Thanks in advance for any clever Apollo 13 style ideas you guys might have.

smartcooky:
It might have been remotely possible to rescue the crew, but the Orbiter itself was doomed. The idea of flying a curved path was pure fantasy

There is a good article here from Nova that outlines a proposed plan for a rescue of the crew using the Orbiter Atlantis

https://www.pbs.org/wgbh/nova/columbia/rescue.html

This ARS Technica article goes some way to explaining just how hard it would have been to transfer the seven crew-members to Atlantis.

https://arstechnica.com/science/2023/02/the-audacious-rescue-plan-that-might-have-saved-space-shuttle-columbia-2/8/

There are couple of interesting constraints including the length of time required to make the crew trasnfers, and the number of crew who can transfer at one time.

IMO, it would have been extremely difficult to do. They are talking about 9 to 24 hours of EVA's to get the whole crew across. It would not take much to go wrong, and you could lose the rescue crew as well.

Allan F:
The Apollo reentry were vastly different from the spacehuttle-reentries. The "skip-out" is not so much a change of course, but the path not slowing down fast enough to stay in the atmosphere. Like sticking a needle in the skin of an orange on a tangent.
The spaceshuttle didn't fall from the moon, remember? Once the deorbit-burn had happened, the ship was on a one-way trip. Not enough energy to go out again. Why don't you get Kerbal Space Programme, which is the most intuitive tool to learn about space-related stuff ever devised by man.

dandypanty:

--- Quote from: smartcooky on August 17, 2023, 07:13:18 PM ---"The idea of flying a curved path was pure fantasy"
But the shuttle actually flew a "curved" path. It banked left and right doing S turns to help control the altitude. I do not know exactly how MUCH curve this was but that is the context of curve I am talking about.

I was trying to find more information about the trajectory of the shuttle during re-entry when I found some interesting information about the Orion capsule that is going to use a skip method. This paragraph interests me the most.
"The heat the spacecraft will experience upon reentry will be split over two events causing a lower heat rate at both occurrences and ultimately making it a safer ride for the astronauts."
I am simply wondering what kind of re-entry would be CONCEPTIALLY possible. For instance: one objection to re-entering over a longer period of time is that the shuttle heat tiles were not designed to sustain the heat for long periods of time. My suggested solution is to skip out multiple times to allow cooling. Objection: the shuttle would need fuel to re-enter the next skip and there isn't enough fuel left during this period of the flight. My suggested solution: send a refueling rocket to top off main engines and thrusters. The main rocket engines could be used to brake a great deal of the speed off so not only would the thrusters be fueled up but they would require much less fuel since the shuttle would only be traveling at perhaps half the original speed. Objection, to fly the skip out method requires MUCH more finesse that the autopilot wasn't programmed to fly. Solution: re-program the computer to fly the new entry program. etc etc. I'm not asking for realistic. I'm asking for conceivable/theoretically. Some of the crazy solutions to broken down space probes that I have read about. Using instruments to perform tasks they weren't designed to. It's hard for me to believe the shuttle could only enter 1 way and that way required a breakup.




--- End quote ---

dandypanty:
"Once the deorbit-burn had happened, the ship was on a one-way trip. Not enough energy to go out again."

Why did the deorbit burn have to be exactly what it was and not another way? Is there only one way the shuttle could re-enter? I understand that the skip couldn't be done on the shuttle because it didn't have the thruster fuel to begin to enter the atmosphere after the skip out however, if the fuel could have been topped off ahead of time, that would allow for a different entrance.

"Why don't you get Kerbal Space Programme, which is the most intuitive tool to learn about space-related stuff ever devised by man."
That's the kind of thing I often imagine I'm going to find some youtuber simulating this very thing but haven't seen it. I just want to know what it would take to make it happen. It survived a long time before breaking up and have a hard time imagining that had they REALLY wanted to get that shuttle back into the atmosphere without a breakup COULD have figured out some way of bringing it down less rapidly (like skipping out multiple times)

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