According to this
site the Soviet Buran shuttle used similar materials and methods to the US Shuttle.
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The gliding descent from the orbit through dense layers of atmosphere has stipulated the necessity to use a principally new reusable thermal protection system designed to sustain 100 flights. For the BURAN orbiter three kinds of thermal protection have been developed:
- "carbon-carbon" material with maximum operating temperature up to 1650 degrees C for the components with the highest thermal load -the fuselage nose and wing leading edge,
- ceramic tiles for parts heating up to 1250 degrees C,
- flexible material for surface parts with the temperature not higher than 379 degrees C.
All of them surpassed by strength the materials used in the USA Space Shuttle construction.
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Question: How were the spherical spacecraft prevented from spinning on reentry initiated by random protrusions on their surfaces?
The unevenness might be there initially or develop as ablation proceeded.
