Interesting... When I was first introduced to the...

2008-10-03T18:27:00.000-07:00

Interesting... When I was first introduced to the EMB-190 aircraft, the autopilot commands the speed of our aircraft either through the elevators (Speed on Elevator, or SPDe) or thrust (Speed on Thrust, or SPDt). So basically a pilot can stall the aircraft in the SPDe mode as the aircraft controls speed with elevator, thus increasing/decreasing angle of attack to maintain a specific airspeed. Therefore we must be vigilant while maneuvering at low altitude to never be in the SPDe mode since the autothrottles could command idle thrust while the angle of attack increases in order to decrease airspeed. The plane will actually keep increasing angle of attack to maintain a certain airspeed at idle thrust until stick shaker.

Ryan

The flight school I work at pretty much uses one D...

2008-09-21T10:49:00.000-07:00

The flight school I work at pretty much uses one DE, a former airline pilot. He addresses this question by bringing up an interesting point - in a modern fighter jet, with a 1:1 or greater thrust:weight ratio, pitch has nothing to do with airspeed. An F-15 can accelerate in the vertical; therefore, airspeed is controlled by power.

Of course, it's a combination of both in any aircraft. I personally am still of the opinion that in a practical sense, pitch more directly controls airspeed, while power affects climb and descent. If you're high on the ILS, you don't just pitch for the glideslope without a power reduction, as you'll accelerate. Likewise, if you climb without adding power, you'll decelerate.

The glider comparison is certainly the easiest way to bring the relationship to a student's attention. When I first demonstrate stall recoveries to students, I do not use power.

Comments on surroundedbyair: Energy Crisis

Interesting... When I was first introduced to the...

The flight school I work at pretty much uses one D...