Question about being unpressurized at higher (Class A) altitudes

Mxsmanic wrote in
:

Matt Barrow writes:

How does the airframe "gain efficiency" at altitude, aside from
generating less drag?

Less drag is a big advantage. The higher an aircraft flies, the more
easily you can move it forward. Ultimately, you end up in outer
space, with no air, and then you don't need any energy at all to keep
it moving forward (the principle behind hypersonic aircraft). This is
one reason why the SR-71 is very efficient in cruise. It's also a
reason why jets fly high even though the engines produce less power at
high altitudes--the power required to maintain a given speed decreases
faster than the power provided by the engines, as altitude increases
(within certain limits).


Wrong again, bozo


Bertie