Right and the SR-70 flys fine at 100KFt which is the pressure at the
surface of Mars and most meteors burn up at even higher alt.
K
On Mon, Mar 1, 2021 at 8:53 AM Kevin Ho <rebelwithoutajob@xxxxxxxxxxx>
wrote:
Drag is quite significant at 40,000 ft. An airplane doing merely 0.8M
requires enormous thrust to maintain speed at that altitude.
On Feb 28, 2021, at 9:55 AM, Dr Edward Jones <RocketPioneer@xxxxxxxxx>wrote:
Thank you. Now suppose the single-stage balloon launch has an overall
mass fraction of 0.90 ... Air launched at 40,000-ft ... drag goes from
"nil" to "nada," correct?