On Tue, 8 Mar 2005 17:24:46 -0500, "Morgans"
wrote:


"Mike Rapoport" wrote

I always thought that the "coffin corner" was where stall speed met the
Mach
limit. I didn't think that it even applied to non-jet aircraft.

Mike

No, I think the post above yours got it pretty much right..Vne is
significant, in that it demonstrates itself by nasty things like flutter, or
control reversal. Pull back on the stick to maneuver, or slow down, and
stall, or at least buffet like hell.

It is true, however, that it is pretty tough for a non jet aircraft to get
to the coffin corner. The Exxon tiger (can't think of the guy's name) that
has been trying to get the piston altitude record, has said that he is
really close to getting into coffin corner.

Another "coffin corner" I have heard discussed is the convergence of
Vne and Vs as altitude increases. I think it went something like
this:

1. Vne is a TAS, so its IAS decreases with increasing altitude.
Vs is an IAS, so as IAS, it remains the same with increasing
altitude.
Therefore, Vne, in IAS converges with Vs in IAS as
altitude increases.
2. Seen the other way, the TAS of Vs increases with altitude,
converging with the fixed TAS of Vne.

Or something like that I guess.