China's Space Program News Thread

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iantsai

Junior Member
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p.s.:

Within 120 to 200 seconds from departure, the reentry module will be protected by the four high-altitude escape engine.

The article doesn't mention the escape mechanism after 200 seconds. Maybe the crew could operate the separation and reentry process manually, or follow the common automatic procedure.
 

Richard Santos

Captain
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I can’t think of any instances, beside space shuttle challenger, where a booster with a manned capsule successfully lifted off but the failed during the ascent.

The failure of the space shuttle challenger was due to a cause not applicable to liquid rocket boosters, and happened so suddenly escape system couldn’t have pulled the crew capsule away in time.

the problem for any escape mechanism that is designed to function after the rocket has been in flight for 120 seconds is when the issue requiring abort occurs, the booster is likely to still be under power and accelerating, and possibly not ntirely under control so the booster stack may be rolling, pitching or yawing. At the same time while entire stack is still in the atmosphere and so encountering high aerodynamic forces. So the escape system has to have enough power to pull the capsule out ahead of the still accelerating booster in the face of aerodynamic forces, and do so fast enough to enable the capsule to clear any explosion of the booster.

it would take fairly powerful rocket engines to do that.
 
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Richard Santos

Captain
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the cost of a escape system that can free a capsule while in flight is weight. no one prior to space X thought it necessarily to invest in an escape system usable during the ascent.

Elon Musk has been very cavalier about safety. he make flippant remarks about people having to die for space travel, i doubt he would invest in going above and beyond for safety.

So my guess is space X needed such a system not to make it extra safe, but to make up for the fact the Falcon rockets Space X uses is perhaps regarded by NASA as not safe enough.
 

taxiya

Brigadier
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According to this article(in Chinese), the cz-2f crewed mission launching system has an escape tower, which works in the first 120 seconds of the launching process. In case of emergency the escape tower will start and separate the reentry module from the rest of the rocket and lift it away for 1500 meters thus the main parachute of the module could be openned safely.

After 120 seconds the escape tower will be kicked away and thereafter the four high-altitude escape engine on the reentry module will help the module separate and reentry safely. In this case the reentry location may be unpredictable, unlike the first stage of the falcon 9.
Thanks for the information. I found an official source from the manned space program office.
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So, yes Shenzhou spacecraft does the same thing "full envelope escape" as SpaceX and Boeing by different means.
 

taxiya

Brigadier
Registered Member
I can’t think of any instances, beside space shuttle challenger, where a booster with a manned capsule successfully lifted off but the failed during the ascent.

The failure of the space shuttle challenger was due to a cause not applicable to liquid rocket boosters, and happened so suddenly escape system couldn’t have pulled the crew capsule away in time.

the problem for any escape mechanism that is designed to function after the rocket has been in flight for 120 seconds is when the issue requiring abort occurs, the booster is likely to still be under power and accelerating, and possibly not ntirely under control so the booster stack may be rolling, pitching or yawing. At the same time while entire stack is still in the atmosphere and so encountering high aerodynamic forces. So the escape system has to have enough power to pull the capsule out ahead of the still accelerating booster in the face of aerodynamic forces, and do so fast enough to enable the capsule to clear any explosion of the booster.

it would take fairly powerful rocket engines to do that.
In 2018 the crew of
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separated from their launch vehicle after a booster rocket separation failure occurred at an altitude of 50 km during the ascent.


Space shuttle is not a proper example to argue for or against any escape system because it is deemed useless or too costly in any scenario by NASA study.

I think you have not read the new post 8142 that says Shenzhen's escape system works up to T+200s (110 km). At T+210s the fairing is discarded, meaning at this time around there is no atmosphere. Shenzhou does what you described.
 

taxiya

Brigadier
Registered Member
p.s.:

Within 120 to 200 seconds from departure, the reentry module will be protected by the four high-altitude escape engine.

The article doesn't mention the escape mechanism after 200 seconds. Maybe the crew could operate the separation and reentry process manually, or follow the common automatic procedure.
A reasonable guess is the main engine of the service module at the bottom of the stack. See the photo below. After 200 seconds, the fairing is jettisoned, the stack is out of the atmosphere, so it is just push and off. The max acceleration has passed, so the service module engine would be enough.
1623792870472.png
 
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Richard Santos

Captain
Registered Member
In 2018 the crew of
Please, Log in or Register to view URLs content!
separated from their launch vehicle after a booster rocket separation failure occurred at an altitude of 50 km during the ascent.


Space shuttle is not a proper example to argue for or against any escape system because it is deemed useless or too costly in any scenario by NASA study.

I think you have not read the new post 8142 that says Shenzhen's escape system works up to T+200s (110 km). At T+210s the fairing is discarded, meaning at this time around there is no atmosphere. Shenzhou does what you described.

Thank you.
 

by78

General
A large composite liquid oxygen storage tank has successfully passed engineering verification. The tank has a diameter of 3.35m and is developed by the 805th Institute of the 8th academy of CASC for future carrier rockets. The low temperature test subjected the tank to 110% (designed?) pressure, and it held.


51250435174_36f1ed142b_o.jpg

51250730435_a832a935a2_o.jpg
 

PiSigma

"the engineer"
A large composite liquid oxygen storage tank has successfully passed engineering verification. The tank has a diameter of 3.35m and is developed by the 805th Institute of the 8th academy of CASC for future carrier rockets. The low temperature test subjected the tank to 110% (designed?) pressure, and it held.


51250435174_36f1ed142b_o.jpg

51250730435_a832a935a2_o.jpg
Testing any vessel past design conditions is standard practice. Hydrotesting to 150% is actually standard practice (no heat). Since this vessel is in extreme cold, the material would suffer thermal stress and brittleness, maybe that's why they only did 110% of design pressure.
 
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