Mike Gammon <jmgammon@sympatico.ca> wrote:
>Concorde is flown by three pilots. Remember this is a 1960s design
>that first saw service in the mid '70s. It is a very complex
>machine, probably the most complex and challenging of all airliners
>to fly.
Two pilots and a flight engineer actually (remember, this is a
European operation).
>It is so sensitive they have to adjust the center of gravity in
>flight by pumping fuel fore and aft.
The aerodynamic centre shifts aft when accelerating to
supersonic speed (from approx 25% to approx 50% of the mean
aerodynamic chord). This can of course be countered by
control deflections, but large permanent control deflections
cause quite a bit of drag. Shifting the centre of gravity to
keep pace with the aerodynamic centre is more efficient
aerodynamically.
An engine failure on Concorde at supersonic speeds is a rather
violent affair. The intake is a finely tuned mechanism with
moving ramps to keep the shockwaves in just the right position.
When an engine suddenly refuses to accept any air flow, the intake
flow has to be dumped overboard and the ramps readjusted. This
causes quite a bit of drag and is accompanied by strong yaw and
roll. Once the situation stabilizes, the slow-down to subsonic
speed and the descent to subsonic flight levels is presumably
intentional and controlled.
Kees de Lezenne Coulander
-- =
C.M. de Lezenne Coulander
Aircraft Development and Systems Engineering B.V.
Hoofddorp, The Netherlands
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