Please consider what the atmospheric density is when the speeds are occurring. On ascent, speeds are increasing as air density decreases. On decent, the shuttle is getting heavier as the air thickens and still needs to bleed off kinetic energy (in the form of heat).

No doubt NASA is lying their asses off about a great many things, but this phenomena fits with established, repeatable physics.

It doesn't matter anyways.

NASA is fake and doesn't send rockets, or any other type of aircraft, into outer space.

The whole Space Shuttle Challenger "disaster" is one of the biggest hoaxes ever.

We ought to be furious with these scammers for monstrous lies, enormous spending for a hoax, and for deceiving the nation and the world. Notice they each received a valuable reward in terms of placement in high paying careers with highly ranked institutions. They are the scum of the earth.