The usual approach to reentry is fast and hot. There's a lot of energy to be lost, and doing it quickly has some advantages: You can dump energy into hypersonic air, and then leave that heat behind so that the hot part is over before the inside of the craft heats up.
As an alternative, what would it take to "fly" a slow reentry?
A typical LEO satellite, for example, is currently doing a stupendously slow reentry, dropping a few km at a time due to drag without significant heating. Eventually, however, when it hits denser atmosphere, it'll start losing energy and altitude fast, and convert to the fast & hot mode, usually burning up.
To avoid that, can a returning spacecraft could "fly" at the very top of the atmosphere for a long time? The craft would only slowly lose speed so keeping thermal issues small, without falling to lower altitude & denser air until the speed is far below orbital speed and normal flight can take over.
Normally, gliding flight is "balance lift and drag to fly at a descent rate that keeps speed constant". This would be more of a "balance lift and drag to fly at a slowly decreasing speed while maintaining altitude"
Is there any research available on what such a profile might look like, and what lift and drag performance would be needed to pull it off? (Even if we can't build such a craft, now or perhaps even ever)
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