Why didn't the Space Shuttle bounce back into space as many times as possible so as to lose a lot of kinetic energy up there? Announcing the arrival of Valued Associate #679: Cesar Manara Unicorn Meta Zoo #1: Why another podcast?If there was a non-rotating skyhook in Earth orbit, what would re-entry be like after dropping from its foot?Why didn't the Space Shuttle have a launch escape system?How many Solid Rocket Boosters were there in the Space Shuttle program?Why didn't NASA use the shuttle to make a profit?While decending from orbit can a blimp glider skip an atmosphere to shed speed?Is getting IN or OUT of orbit easier for the Space Shuttle?Why didn't the space shuttle SRBs have wings and tires?Why didn't the SRBs of the Space Shuttle use carbon instead of aluminium?How many times were there thirteen people inside the ISS? Is it hard on the station?Why didn't the space shuttle use non-foam-shedding external tanks?Why can't you just parachute down right from orbit?

I preordered a game on my Xbox while on the home screen of my friend's account. Which of us owns the game?

Why did Israel vote against lifting the American embargo on Cuba?

Retract an already submitted recommendation letter (written for an undergrad student)

Is it acceptable to use working hours to read general interest books?

Is Diceware more secure than a long passphrase?

What was Apollo 13's "Little Jolt" after MECO?

"Whatever a Russian does, they end up making the Kalashnikov gun"? Are there any similar proverbs in English?

What is it called when you ride around on your front wheel?

The art of proof summarizing. Are there known rules, or is it a purely common sense matter?

What is ls Largest Number Formed by only moving two sticks in 508?

Why is this method for solving linear equations systems using determinants works?

Is Electric Central Heating worth it if using Solar Panels?

"Rubric" as meaning "signature" or "personal mark" -- is this accepted usage?

How to translate "red flag" into Spanish?

Is a 5 watt UHF/VHF handheld considered QRP?

Married in secret, can marital status in passport be changed at a later date?

Is accepting an invalid credit card number a security issue?

Visa-free travel to the US using refugee travel document from Spain?

Is there any hidden 'W' sound after 'comment' in : Comment est-elle?

How long after the last departure shall the airport stay open for an emergency return?

How to keep bees out of canned beverages?

Is Bran literally the world's memory?

Expansion//Explosion and Siren Stormtamer

Are these square matrices always diagonalisable?



Why didn't the Space Shuttle bounce back into space as many times as possible so as to lose a lot of kinetic energy up there?



Announcing the arrival of Valued Associate #679: Cesar Manara
Unicorn Meta Zoo #1: Why another podcast?If there was a non-rotating skyhook in Earth orbit, what would re-entry be like after dropping from its foot?Why didn't the Space Shuttle have a launch escape system?How many Solid Rocket Boosters were there in the Space Shuttle program?Why didn't NASA use the shuttle to make a profit?While decending from orbit can a blimp glider skip an atmosphere to shed speed?Is getting IN or OUT of orbit easier for the Space Shuttle?Why didn't the space shuttle SRBs have wings and tires?Why didn't the SRBs of the Space Shuttle use carbon instead of aluminium?How many times were there thirteen people inside the ISS? Is it hard on the station?Why didn't the space shuttle use non-foam-shedding external tanks?Why can't you just parachute down right from orbit?










21












$begingroup$


From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it bounces back to space.
Why don't we let the Shuttle bounce back into space many times as possible and skim a lot of atmosphere so that it loose lot of kinetic energy over there? I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.










share|improve this question











$endgroup$











  • $begingroup$
    To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
    $endgroup$
    – Bret Copeland
    17 hours ago






  • 8




    $begingroup$
    5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
    $endgroup$
    – Mazura
    14 hours ago















21












$begingroup$


From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it bounces back to space.
Why don't we let the Shuttle bounce back into space many times as possible and skim a lot of atmosphere so that it loose lot of kinetic energy over there? I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.










share|improve this question











$endgroup$











  • $begingroup$
    To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
    $endgroup$
    – Bret Copeland
    17 hours ago






  • 8




    $begingroup$
    5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
    $endgroup$
    – Mazura
    14 hours ago













21












21








21





$begingroup$


From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it bounces back to space.
Why don't we let the Shuttle bounce back into space many times as possible and skim a lot of atmosphere so that it loose lot of kinetic energy over there? I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.










share|improve this question











$endgroup$




From this video, I got know that Space Shuttle did reentry around 5000 miles away from landing site. It's angle of attack is maintained around 40 degrees during re-entry. If it is more than that, it bounces back to space.
Why don't we let the Shuttle bounce back into space many times as possible and skim a lot of atmosphere so that it loose lot of kinetic energy over there? I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.







space-shuttle reentry






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 1 hour ago









MackTuesday

1033




1033










asked 22 hours ago









SRDSRD

32318




32318











  • $begingroup$
    To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
    $endgroup$
    – Bret Copeland
    17 hours ago






  • 8




    $begingroup$
    5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
    $endgroup$
    – Mazura
    14 hours ago
















  • $begingroup$
    To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
    $endgroup$
    – Bret Copeland
    17 hours ago






  • 8




    $begingroup$
    5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
    $endgroup$
    – Mazura
    14 hours ago















$begingroup$
To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
$endgroup$
– Bret Copeland
17 hours ago




$begingroup$
To be clear, it's not AoA which prevents the shuttle from skipping; it's banking - pointing the lift vector sideways instead of up. An increase in AoA from 40° would most likely reduce the chance of skipping.
$endgroup$
– Bret Copeland
17 hours ago




8




8




$begingroup$
5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
$endgroup$
– Mazura
14 hours ago




$begingroup$
5000 nautical miles away. The answer is in the video but easy to miss; he notes very quickly, and only once, that slowing too much: you'll drop out the sky like a rock (which is the penultimate concern at all times only to 'rapid unplanned disassembly'). It's bad enough that it's already a flying brick.
$endgroup$
– Mazura
14 hours ago










2 Answers
2






active

oldest

votes


















30












$begingroup$


I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.




Your thinking is reasonable as far as it goes...



But once you lose too much velocity and become deeply sub-orbital, you will sink like a rock into thicker atmosphere.



Within five minutes you'll either be toast from heating or jelly from pulling 15-20 gees.



In this answer I did a calculation for a different spacecraft (a Dragon capsule) with lift to drag between 0 and 0.3 and the scenario was always the same. Being significantly slower results in falling too deeply to quickly, and the higher density results in huge heat production and unsurvivably large accelerations.



everyone dies in five minutes






share|improve this answer











$endgroup$








  • 3




    $begingroup$
    uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
    $endgroup$
    – Arris
    5 hours ago






  • 3




    $begingroup$
    @Arris uhoh is all about the python, not XL.
    $endgroup$
    – Organic Marble
    5 hours ago







  • 2




    $begingroup$
    It's "lose", not loose. Too short for me to do an edit.
    $endgroup$
    – Monty Harder
    3 hours ago










  • $begingroup$
    @MontyHarder thank you for that. For some reason those two wires are permanently crossed.
    $endgroup$
    – uhoh
    2 hours ago


















36












$begingroup$

Skipping reentries aren't unheard of. The Apollo command module performed a single skip when returning from lunar missions. However, there are several reasons why a skipping reentry (especially one involving multiple skips) would be disadvantageous for the shuttle:



  1. As uhoh points out, a skipping reentry results in losing lateral speed at a very high altitude. In turn, you lose the ability to control your descent rate. By the end of entry you'd practically be in a free-fall which the vehicle would be unlikely to survive due to the heat and/or stress of attempting to pull out of the dive.

  2. The shuttle's thermal protection system was not designed to withstand long drawn-out reentries. Here's a quote from the "Entry, TAEM, and Approach/Landing Guidance Workbook":


    On the flip side of high surface temperatures, there are high backface temperatures. If
    you fly at high temperatures for a long time, heat will flow through the tiles to the
    aluminum underneath. This can happen if you fly a low drag profile. In fact, backface
    temperature is the current low limit to the drag profile.




  3. Several other systems weren't designed for long drawn-out reentries either. The APUs only have the fuel capacity to run for about 110 minutes, which wouldn't be enough to support both launch and an extended reentry. The radiators, which were cold-soaked before entry, may have needed additional capacity to absorb heat build up during entry. The RCS may have needed more reserves.

  4. Flying a low-drag profile gives you less margin for error. Flying a middle-of-the-road drag profile means you have room to increase or decrease your drag as necessary in order to make the landing site. If your designed flight path is already on the low-end and you end up in a low energy condition, there's not much you can do about it.

  5. It's not impossible to develop guidance for a skipping reentry, but it is definitely a more difficult problem.

I suspect there are other reasons I haven't thought of.



On the flip side, I can't think of any advantages. The shuttle's reentry was already comparatively gentle (well under 2g's the whole time) and the heat was perfectly managable as-is.






share|improve this answer











$endgroup$












  • $begingroup$
    This is a very thorough answer, +1!
    $endgroup$
    – uhoh
    15 hours ago










  • $begingroup$
    +1 for the limitations due to other systems.
    $endgroup$
    – Organic Marble
    10 hours ago










  • $begingroup$
    The APU's a non-issue (it had power for days) but everything else seems right.
    $endgroup$
    – Joshua
    9 hours ago






  • 2




    $begingroup$
    @Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
    $endgroup$
    – Bret Copeland
    6 hours ago










  • $begingroup$
    @BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
    $endgroup$
    – Joshua
    5 hours ago











Your Answer








StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "508"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);













draft saved

draft discarded


















StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fspace.stackexchange.com%2fquestions%2f35741%2fwhy-didnt-the-space-shuttle-bounce-back-into-space-as-many-times-as-possible-so%23new-answer', 'question_page');

);

Post as a guest















Required, but never shown

























2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









30












$begingroup$


I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.




Your thinking is reasonable as far as it goes...



But once you lose too much velocity and become deeply sub-orbital, you will sink like a rock into thicker atmosphere.



Within five minutes you'll either be toast from heating or jelly from pulling 15-20 gees.



In this answer I did a calculation for a different spacecraft (a Dragon capsule) with lift to drag between 0 and 0.3 and the scenario was always the same. Being significantly slower results in falling too deeply to quickly, and the higher density results in huge heat production and unsurvivably large accelerations.



everyone dies in five minutes






share|improve this answer











$endgroup$








  • 3




    $begingroup$
    uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
    $endgroup$
    – Arris
    5 hours ago






  • 3




    $begingroup$
    @Arris uhoh is all about the python, not XL.
    $endgroup$
    – Organic Marble
    5 hours ago







  • 2




    $begingroup$
    It's "lose", not loose. Too short for me to do an edit.
    $endgroup$
    – Monty Harder
    3 hours ago










  • $begingroup$
    @MontyHarder thank you for that. For some reason those two wires are permanently crossed.
    $endgroup$
    – uhoh
    2 hours ago















30












$begingroup$


I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.




Your thinking is reasonable as far as it goes...



But once you lose too much velocity and become deeply sub-orbital, you will sink like a rock into thicker atmosphere.



Within five minutes you'll either be toast from heating or jelly from pulling 15-20 gees.



In this answer I did a calculation for a different spacecraft (a Dragon capsule) with lift to drag between 0 and 0.3 and the scenario was always the same. Being significantly slower results in falling too deeply to quickly, and the higher density results in huge heat production and unsurvivably large accelerations.



everyone dies in five minutes






share|improve this answer











$endgroup$








  • 3




    $begingroup$
    uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
    $endgroup$
    – Arris
    5 hours ago






  • 3




    $begingroup$
    @Arris uhoh is all about the python, not XL.
    $endgroup$
    – Organic Marble
    5 hours ago







  • 2




    $begingroup$
    It's "lose", not loose. Too short for me to do an edit.
    $endgroup$
    – Monty Harder
    3 hours ago










  • $begingroup$
    @MontyHarder thank you for that. For some reason those two wires are permanently crossed.
    $endgroup$
    – uhoh
    2 hours ago













30












30








30





$begingroup$


I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.




Your thinking is reasonable as far as it goes...



But once you lose too much velocity and become deeply sub-orbital, you will sink like a rock into thicker atmosphere.



Within five minutes you'll either be toast from heating or jelly from pulling 15-20 gees.



In this answer I did a calculation for a different spacecraft (a Dragon capsule) with lift to drag between 0 and 0.3 and the scenario was always the same. Being significantly slower results in falling too deeply to quickly, and the higher density results in huge heat production and unsurvivably large accelerations.



everyone dies in five minutes






share|improve this answer











$endgroup$




I think bounce back causes intermittent heating so heat shield tiles get a lot of time of radiate heat out.




Your thinking is reasonable as far as it goes...



But once you lose too much velocity and become deeply sub-orbital, you will sink like a rock into thicker atmosphere.



Within five minutes you'll either be toast from heating or jelly from pulling 15-20 gees.



In this answer I did a calculation for a different spacecraft (a Dragon capsule) with lift to drag between 0 and 0.3 and the scenario was always the same. Being significantly slower results in falling too deeply to quickly, and the higher density results in huge heat production and unsurvivably large accelerations.



everyone dies in five minutes







share|improve this answer














share|improve this answer



share|improve this answer








edited 2 hours ago

























answered 22 hours ago









uhohuhoh

41.7k19158522




41.7k19158522







  • 3




    $begingroup$
    uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
    $endgroup$
    – Arris
    5 hours ago






  • 3




    $begingroup$
    @Arris uhoh is all about the python, not XL.
    $endgroup$
    – Organic Marble
    5 hours ago







  • 2




    $begingroup$
    It's "lose", not loose. Too short for me to do an edit.
    $endgroup$
    – Monty Harder
    3 hours ago










  • $begingroup$
    @MontyHarder thank you for that. For some reason those two wires are permanently crossed.
    $endgroup$
    – uhoh
    2 hours ago












  • 3




    $begingroup$
    uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
    $endgroup$
    – Arris
    5 hours ago






  • 3




    $begingroup$
    @Arris uhoh is all about the python, not XL.
    $endgroup$
    – Organic Marble
    5 hours ago







  • 2




    $begingroup$
    It's "lose", not loose. Too short for me to do an edit.
    $endgroup$
    – Monty Harder
    3 hours ago










  • $begingroup$
    @MontyHarder thank you for that. For some reason those two wires are permanently crossed.
    $endgroup$
    – uhoh
    2 hours ago







3




3




$begingroup$
uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
$endgroup$
– Arris
5 hours ago




$begingroup$
uhoh, you just owe to the community the tools (Excel formulas, I believe) you used to make these charts.
$endgroup$
– Arris
5 hours ago




3




3




$begingroup$
@Arris uhoh is all about the python, not XL.
$endgroup$
– Organic Marble
5 hours ago





$begingroup$
@Arris uhoh is all about the python, not XL.
$endgroup$
– Organic Marble
5 hours ago





2




2




$begingroup$
It's "lose", not loose. Too short for me to do an edit.
$endgroup$
– Monty Harder
3 hours ago




$begingroup$
It's "lose", not loose. Too short for me to do an edit.
$endgroup$
– Monty Harder
3 hours ago












$begingroup$
@MontyHarder thank you for that. For some reason those two wires are permanently crossed.
$endgroup$
– uhoh
2 hours ago




$begingroup$
@MontyHarder thank you for that. For some reason those two wires are permanently crossed.
$endgroup$
– uhoh
2 hours ago











36












$begingroup$

Skipping reentries aren't unheard of. The Apollo command module performed a single skip when returning from lunar missions. However, there are several reasons why a skipping reentry (especially one involving multiple skips) would be disadvantageous for the shuttle:



  1. As uhoh points out, a skipping reentry results in losing lateral speed at a very high altitude. In turn, you lose the ability to control your descent rate. By the end of entry you'd practically be in a free-fall which the vehicle would be unlikely to survive due to the heat and/or stress of attempting to pull out of the dive.

  2. The shuttle's thermal protection system was not designed to withstand long drawn-out reentries. Here's a quote from the "Entry, TAEM, and Approach/Landing Guidance Workbook":


    On the flip side of high surface temperatures, there are high backface temperatures. If
    you fly at high temperatures for a long time, heat will flow through the tiles to the
    aluminum underneath. This can happen if you fly a low drag profile. In fact, backface
    temperature is the current low limit to the drag profile.




  3. Several other systems weren't designed for long drawn-out reentries either. The APUs only have the fuel capacity to run for about 110 minutes, which wouldn't be enough to support both launch and an extended reentry. The radiators, which were cold-soaked before entry, may have needed additional capacity to absorb heat build up during entry. The RCS may have needed more reserves.

  4. Flying a low-drag profile gives you less margin for error. Flying a middle-of-the-road drag profile means you have room to increase or decrease your drag as necessary in order to make the landing site. If your designed flight path is already on the low-end and you end up in a low energy condition, there's not much you can do about it.

  5. It's not impossible to develop guidance for a skipping reentry, but it is definitely a more difficult problem.

I suspect there are other reasons I haven't thought of.



On the flip side, I can't think of any advantages. The shuttle's reentry was already comparatively gentle (well under 2g's the whole time) and the heat was perfectly managable as-is.






share|improve this answer











$endgroup$












  • $begingroup$
    This is a very thorough answer, +1!
    $endgroup$
    – uhoh
    15 hours ago










  • $begingroup$
    +1 for the limitations due to other systems.
    $endgroup$
    – Organic Marble
    10 hours ago










  • $begingroup$
    The APU's a non-issue (it had power for days) but everything else seems right.
    $endgroup$
    – Joshua
    9 hours ago






  • 2




    $begingroup$
    @Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
    $endgroup$
    – Bret Copeland
    6 hours ago










  • $begingroup$
    @BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
    $endgroup$
    – Joshua
    5 hours ago















36












$begingroup$

Skipping reentries aren't unheard of. The Apollo command module performed a single skip when returning from lunar missions. However, there are several reasons why a skipping reentry (especially one involving multiple skips) would be disadvantageous for the shuttle:



  1. As uhoh points out, a skipping reentry results in losing lateral speed at a very high altitude. In turn, you lose the ability to control your descent rate. By the end of entry you'd practically be in a free-fall which the vehicle would be unlikely to survive due to the heat and/or stress of attempting to pull out of the dive.

  2. The shuttle's thermal protection system was not designed to withstand long drawn-out reentries. Here's a quote from the "Entry, TAEM, and Approach/Landing Guidance Workbook":


    On the flip side of high surface temperatures, there are high backface temperatures. If
    you fly at high temperatures for a long time, heat will flow through the tiles to the
    aluminum underneath. This can happen if you fly a low drag profile. In fact, backface
    temperature is the current low limit to the drag profile.




  3. Several other systems weren't designed for long drawn-out reentries either. The APUs only have the fuel capacity to run for about 110 minutes, which wouldn't be enough to support both launch and an extended reentry. The radiators, which were cold-soaked before entry, may have needed additional capacity to absorb heat build up during entry. The RCS may have needed more reserves.

  4. Flying a low-drag profile gives you less margin for error. Flying a middle-of-the-road drag profile means you have room to increase or decrease your drag as necessary in order to make the landing site. If your designed flight path is already on the low-end and you end up in a low energy condition, there's not much you can do about it.

  5. It's not impossible to develop guidance for a skipping reentry, but it is definitely a more difficult problem.

I suspect there are other reasons I haven't thought of.



On the flip side, I can't think of any advantages. The shuttle's reentry was already comparatively gentle (well under 2g's the whole time) and the heat was perfectly managable as-is.






share|improve this answer











$endgroup$












  • $begingroup$
    This is a very thorough answer, +1!
    $endgroup$
    – uhoh
    15 hours ago










  • $begingroup$
    +1 for the limitations due to other systems.
    $endgroup$
    – Organic Marble
    10 hours ago










  • $begingroup$
    The APU's a non-issue (it had power for days) but everything else seems right.
    $endgroup$
    – Joshua
    9 hours ago






  • 2




    $begingroup$
    @Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
    $endgroup$
    – Bret Copeland
    6 hours ago










  • $begingroup$
    @BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
    $endgroup$
    – Joshua
    5 hours ago













36












36








36





$begingroup$

Skipping reentries aren't unheard of. The Apollo command module performed a single skip when returning from lunar missions. However, there are several reasons why a skipping reentry (especially one involving multiple skips) would be disadvantageous for the shuttle:



  1. As uhoh points out, a skipping reentry results in losing lateral speed at a very high altitude. In turn, you lose the ability to control your descent rate. By the end of entry you'd practically be in a free-fall which the vehicle would be unlikely to survive due to the heat and/or stress of attempting to pull out of the dive.

  2. The shuttle's thermal protection system was not designed to withstand long drawn-out reentries. Here's a quote from the "Entry, TAEM, and Approach/Landing Guidance Workbook":


    On the flip side of high surface temperatures, there are high backface temperatures. If
    you fly at high temperatures for a long time, heat will flow through the tiles to the
    aluminum underneath. This can happen if you fly a low drag profile. In fact, backface
    temperature is the current low limit to the drag profile.




  3. Several other systems weren't designed for long drawn-out reentries either. The APUs only have the fuel capacity to run for about 110 minutes, which wouldn't be enough to support both launch and an extended reentry. The radiators, which were cold-soaked before entry, may have needed additional capacity to absorb heat build up during entry. The RCS may have needed more reserves.

  4. Flying a low-drag profile gives you less margin for error. Flying a middle-of-the-road drag profile means you have room to increase or decrease your drag as necessary in order to make the landing site. If your designed flight path is already on the low-end and you end up in a low energy condition, there's not much you can do about it.

  5. It's not impossible to develop guidance for a skipping reentry, but it is definitely a more difficult problem.

I suspect there are other reasons I haven't thought of.



On the flip side, I can't think of any advantages. The shuttle's reentry was already comparatively gentle (well under 2g's the whole time) and the heat was perfectly managable as-is.






share|improve this answer











$endgroup$



Skipping reentries aren't unheard of. The Apollo command module performed a single skip when returning from lunar missions. However, there are several reasons why a skipping reentry (especially one involving multiple skips) would be disadvantageous for the shuttle:



  1. As uhoh points out, a skipping reentry results in losing lateral speed at a very high altitude. In turn, you lose the ability to control your descent rate. By the end of entry you'd practically be in a free-fall which the vehicle would be unlikely to survive due to the heat and/or stress of attempting to pull out of the dive.

  2. The shuttle's thermal protection system was not designed to withstand long drawn-out reentries. Here's a quote from the "Entry, TAEM, and Approach/Landing Guidance Workbook":


    On the flip side of high surface temperatures, there are high backface temperatures. If
    you fly at high temperatures for a long time, heat will flow through the tiles to the
    aluminum underneath. This can happen if you fly a low drag profile. In fact, backface
    temperature is the current low limit to the drag profile.




  3. Several other systems weren't designed for long drawn-out reentries either. The APUs only have the fuel capacity to run for about 110 minutes, which wouldn't be enough to support both launch and an extended reentry. The radiators, which were cold-soaked before entry, may have needed additional capacity to absorb heat build up during entry. The RCS may have needed more reserves.

  4. Flying a low-drag profile gives you less margin for error. Flying a middle-of-the-road drag profile means you have room to increase or decrease your drag as necessary in order to make the landing site. If your designed flight path is already on the low-end and you end up in a low energy condition, there's not much you can do about it.

  5. It's not impossible to develop guidance for a skipping reentry, but it is definitely a more difficult problem.

I suspect there are other reasons I haven't thought of.



On the flip side, I can't think of any advantages. The shuttle's reentry was already comparatively gentle (well under 2g's the whole time) and the heat was perfectly managable as-is.







share|improve this answer














share|improve this answer



share|improve this answer








edited 6 hours ago

























answered 16 hours ago









Bret CopelandBret Copeland

54437




54437











  • $begingroup$
    This is a very thorough answer, +1!
    $endgroup$
    – uhoh
    15 hours ago










  • $begingroup$
    +1 for the limitations due to other systems.
    $endgroup$
    – Organic Marble
    10 hours ago










  • $begingroup$
    The APU's a non-issue (it had power for days) but everything else seems right.
    $endgroup$
    – Joshua
    9 hours ago






  • 2




    $begingroup$
    @Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
    $endgroup$
    – Bret Copeland
    6 hours ago










  • $begingroup$
    @BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
    $endgroup$
    – Joshua
    5 hours ago
















  • $begingroup$
    This is a very thorough answer, +1!
    $endgroup$
    – uhoh
    15 hours ago










  • $begingroup$
    +1 for the limitations due to other systems.
    $endgroup$
    – Organic Marble
    10 hours ago










  • $begingroup$
    The APU's a non-issue (it had power for days) but everything else seems right.
    $endgroup$
    – Joshua
    9 hours ago






  • 2




    $begingroup$
    @Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
    $endgroup$
    – Bret Copeland
    6 hours ago










  • $begingroup$
    @BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
    $endgroup$
    – Joshua
    5 hours ago















$begingroup$
This is a very thorough answer, +1!
$endgroup$
– uhoh
15 hours ago




$begingroup$
This is a very thorough answer, +1!
$endgroup$
– uhoh
15 hours ago












$begingroup$
+1 for the limitations due to other systems.
$endgroup$
– Organic Marble
10 hours ago




$begingroup$
+1 for the limitations due to other systems.
$endgroup$
– Organic Marble
10 hours ago












$begingroup$
The APU's a non-issue (it had power for days) but everything else seems right.
$endgroup$
– Joshua
9 hours ago




$begingroup$
The APU's a non-issue (it had power for days) but everything else seems right.
$endgroup$
– Joshua
9 hours ago




2




2




$begingroup$
@Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
$endgroup$
– Bret Copeland
6 hours ago




$begingroup$
@Joshua no, the APUs had very little fuel reserves. See the Shuttle Crew Operations Manual page 2.1-2: "The hydrazine is stored in a fuel tank with a total capacity of about 350 pounds.... The fuel supply supports the nominal power unit operating time of 90 minutes in a mission or any defined abort mode, such as an abort once around, when the APUs run continuously for approximately 110 minutes. Under operating load conditions, an APU consumes approximately 3 to 3.5 pounds of fuel per minute."
$endgroup$
– Bret Copeland
6 hours ago












$begingroup$
@BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
$endgroup$
– Joshua
5 hours ago




$begingroup$
@BretCopeland: Seems I mixed it up with the on-orbit fuel cells. nasa.gov/topics/technology/hydrogen/fc_shuttle.html
$endgroup$
– Joshua
5 hours ago

















draft saved

draft discarded
















































Thanks for contributing an answer to Space Exploration Stack Exchange!


  • Please be sure to answer the question. Provide details and share your research!

But avoid


  • Asking for help, clarification, or responding to other answers.

  • Making statements based on opinion; back them up with references or personal experience.

Use MathJax to format equations. MathJax reference.


To learn more, see our tips on writing great answers.




draft saved


draft discarded














StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fspace.stackexchange.com%2fquestions%2f35741%2fwhy-didnt-the-space-shuttle-bounce-back-into-space-as-many-times-as-possible-so%23new-answer', 'question_page');

);

Post as a guest















Required, but never shown





















































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown

































Required, but never shown














Required, but never shown












Required, but never shown







Required, but never shown







Popular posts from this blog

Францішак Багушэвіч Змест Сям'я | Біяграфія | Творчасць | Мова Багушэвіча | Ацэнкі дзейнасці | Цікавыя факты | Спадчына | Выбраная бібліяграфія | Ушанаванне памяці | У філатэліі | Зноскі | Літаратура | Спасылкі | НавігацыяЛяхоўскі У. Рупіўся дзеля Бога і людзей: Жыццёвы шлях Лявона Вітан-Дубейкаўскага // Вольскі і Памідораў з песняй пра немца Адвакат, паэт, народны заступнік Ашмянскі веснікВ Минске появится площадь Богушевича и улица Сырокомли, Белорусская деловая газета, 19 июля 2001 г.Айцец беларускай нацыянальнай ідэі паўстаў у бронзе Сяргей Аляксандравіч Адашкевіч (1918, Мінск). 80-я гады. Бюст «Францішак Багушэвіч».Яўген Мікалаевіч Ціхановіч. «Партрэт Францішка Багушэвіча»Мікола Мікалаевіч Купава. «Партрэт зачынальніка новай беларускай літаратуры Францішка Багушэвіча»Уладзімір Іванавіч Мелехаў. На помніку «Змагарам за родную мову» Барэльеф «Францішак Багушэвіч»Памяць пра Багушэвіча на Віленшчыне Страчаная сталіца. Беларускія шыльды на вуліцах Вільні«Krynica». Ideologia i przywódcy białoruskiego katolicyzmuФранцішак БагушэвічТворы на knihi.comТворы Францішка Багушэвіча на bellib.byСодаль Уладзімір. Францішак Багушэвіч на Лідчыне;Луцкевіч Антон. Жыцьцё і творчасьць Фр. Багушэвіча ў успамінах ягоных сучасьнікаў // Запісы Беларускага Навуковага таварыства. Вільня, 1938. Сшытак 1. С. 16-34.Большая российская1188761710000 0000 5537 633Xn9209310021619551927869394п

Беларусь Змест Назва Гісторыя Геаграфія Сімволіка Дзяржаўны лад Палітычныя партыі Міжнароднае становішча і знешняя палітыка Адміністрацыйны падзел Насельніцтва Эканоміка Культура і грамадства Сацыяльная сфера Узброеныя сілы Заўвагі Літаратура Спасылкі НавігацыяHGЯOiТоп-2011 г. (па версіі ej.by)Топ-2013 г. (па версіі ej.by)Топ-2016 г. (па версіі ej.by)Топ-2017 г. (па версіі ej.by)Нацыянальны статыстычны камітэт Рэспублікі БеларусьШчыльнасць насельніцтва па краінахhttp://naviny.by/rubrics/society/2011/09/16/ic_articles_116_175144/А. Калечыц, У. Ксяндзоў. Спробы засялення краю неандэртальскім чалавекам.І ў Менску былі мамантыА. Калечыц, У. Ксяндзоў. Старажытны каменны век (палеаліт). Першапачатковае засяленне тэрыторыіГ. Штыхаў. Балты і славяне ў VI—VIII стст.М. Клімаў. Полацкае княства ў IX—XI стст.Г. Штыхаў, В. Ляўко. Палітычная гісторыя Полацкай зямліГ. Штыхаў. Дзяржаўны лад у землях-княствахГ. Штыхаў. Дзяржаўны лад у землях-княствахБеларускія землі ў складзе Вялікага Княства ЛітоўскагаЛюблінская унія 1569 г."The Early Stages of Independence"Zapomniane prawdy25 гадоў таму было аб'яўлена, што Язэп Пілсудскі — беларус (фота)Наша вадаДакументы ЧАЭС: Забруджванне тэрыторыі Беларусі « ЧАЭС Зона адчужэнняСведения о политических партиях, зарегистрированных в Республике Беларусь // Министерство юстиции Республики БеларусьСтатыстычны бюлетэнь „Полаўзроставая структура насельніцтва Рэспублікі Беларусь на 1 студзеня 2012 года і сярэднегадовая колькасць насельніцтва за 2011 год“Индекс человеческого развития Беларуси — не было бы нижеБеларусь занимает первое место в СНГ по индексу развития с учетом гендерного факцёраНацыянальны статыстычны камітэт Рэспублікі БеларусьКанстытуцыя РБ. Артыкул 17Трансфармацыйныя задачы БеларусіВыйсце з крызісу — далейшае рэфармаванне Беларускі рубель — сусветны лідар па дэвальвацыяхПра змену коштаў у кастрычніку 2011 г.Бядней за беларусаў у СНД толькі таджыкіСярэдні заробак у верасні дасягнуў 2,26 мільёна рублёўЭканомікаГаласуем за ТОП-100 беларускай прозыСучасныя беларускія мастакіАрхитектура Беларуси BELARUS.BYА. Каханоўскі. Культура Беларусі ўсярэдзіне XVII—XVIII ст.Анталогія беларускай народнай песні, гуказапісы спеваўБеларускія Музычныя IнструментыБеларускі рок, які мы страцілі. Топ-10 гуртоў«Мясцовы час» — нязгаслая легенда беларускай рок-музыкіСЯРГЕЙ БУДКІН. МЫ НЯ ЗНАЕМ СВАЁЙ МУЗЫКІМ. А. Каладзінскі. НАРОДНЫ ТЭАТРМагнацкія культурныя цэнтрыПублічная дыскусія «Беларуская новая пьеса: без беларускай мовы ці беларуская?»Беларускія драматургі па-ранейшаму лепш ставяцца за мяжой, чым на радзіме«Працэс незалежнага кіно пайшоў, і дзяржаву турбуе яго непадкантрольнасць»Беларускія філосафы ў пошуках прасторыВсе идём в библиотекуАрхіваванаАб Нацыянальнай праграме даследавання і выкарыстання касмічнай прасторы ў мірных мэтах на 2008—2012 гадыУ космас — разам.У суседнім з Барысаўскім раёне пабудуюць Камандна-вымяральны пунктСвяты і абрады беларусаў«Мірныя бульбашы з малой краіны» — 5 непраўдзівых стэрэатыпаў пра БеларусьМ. Раманюк. Беларускае народнае адзеннеУ Беларусі скарачаецца колькасць злачынстваўЛукашэнка незадаволены мінскімі ўладамі Крадзяжы складаюць у Мінску каля 70% злачынстваў Узровень злачыннасці ў Мінскай вобласці — адзін з самых высокіх у краіне Генпракуратура аналізуе стан са злачыннасцю ў Беларусі па каэфіцыенце злачыннасці У Беларусі стабілізавалася крымінагеннае становішча, лічыць генпракурорЗамежнікі сталі здзяйсняць у Беларусі больш злачынстваўМУС Беларусі турбуе рост рэцыдыўнай злачыннасціЯ з ЖЭСа. Дазволіце вас абкрасці! Рэйтынг усіх службаў і падраздзяленняў ГУУС Мінгарвыканкама вырасАб КДБ РБГісторыя Аператыўна-аналітычнага цэнтра РБГісторыя ДКФРТаможняagentura.ruБеларусьBelarus.by — Афіцыйны сайт Рэспублікі БеларусьСайт урада БеларусіRadzima.org — Збор архітэктурных помнікаў, гісторыя Беларусі«Глобус Беларуси»Гербы и флаги БеларусиАсаблівасці каменнага веку на БеларусіА. Калечыц, У. Ксяндзоў. Старажытны каменны век (палеаліт). Першапачатковае засяленне тэрыторыіУ. Ксяндзоў. Сярэдні каменны век (мезаліт). Засяленне краю плямёнамі паляўнічых, рыбакоў і збіральнікаўА. Калечыц, М. Чарняўскі. Плямёны на тэрыторыі Беларусі ў новым каменным веку (неаліце)А. Калечыц, У. Ксяндзоў, М. Чарняўскі. Гаспадарчыя заняткі ў каменным векуЭ. Зайкоўскі. Духоўная культура ў каменным векуАсаблівасці бронзавага веку на БеларусіФарміраванне супольнасцей ранняга перыяду бронзавага векуФотографии БеларусиРоля беларускіх зямель ва ўтварэнні і ўмацаванні ВКЛВ. Фадзеева. З гісторыі развіцця беларускай народнай вышыўкіDMOZGran catalanaБольшая российскаяBritannica (анлайн)Швейцарскі гістарычны15325917611952699xDA123282154079143-90000 0001 2171 2080n9112870100577502ge128882171858027501086026362074122714179пппппп

ValueError: Expected n_neighbors <= n_samples, but n_samples = 1, n_neighbors = 6 (SMOTE) The 2019 Stack Overflow Developer Survey Results Are InCan SMOTE be applied over sequence of words (sentences)?ValueError when doing validation with random forestsSMOTE and multi class oversamplingLogic behind SMOTE-NC?ValueError: Error when checking target: expected dense_1 to have shape (7,) but got array with shape (1,)SmoteBoost: Should SMOTE be ran individually for each iteration/tree in the boosting?solving multi-class imbalance classification using smote and OSSUsing SMOTE for Synthetic Data generation to improve performance on unbalanced dataproblem of entry format for a simple model in KerasSVM SMOTE fit_resample() function runs forever with no result