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Old 12-30-2011 | 02:24 PM
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UAL T38 Phlyer
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From: Curator at Static Display
Default Similarities, and Applied Aerodynamics

The high-g profile described in the article works because fighters are generally low-aspect ratio wings. At high g (AOA), there are huge drag penalties due to tip-losses/vortices.

The same principle works in GA aircraft, as you have noted, just not quite as well. Most fighters have an aspect of about 6; GA is usually around 10-12, if memory serves. GA losses due to vortices are a much smaller percentage of the drag on the airplane.

The article said fighters can't use a slip: I have, and continue to do so (this is in the F-4 and the T-38). Fly-by-wires may not cooperate as much, but I think it can still be done (ie, step on the rudder in an F-16, and it deflects---but the ailerons would auto-deflect to prevent the roll that happens in swept-wings with yaw).

I did an emergency decent in the sim (for a checkride) simulating cabin-pressure loss in the Lear 35 a little differently than the book. We normally just went to idle, dropped the gear, popped spoilers, and held it straight-ahead at redline speed. From 40,000 ft, it took about 7 minutes to get down to 10,000.

I did all that, but went into a 60-degree-bank turn and used bank to keep the pitch at its normal mark (I think it was 10 degrees). IE, I was holding 2-gs.

The Sim guy said "Hey, what are you doing?" I had my FO give the "ATC, we are orbiting at present position in our descent" call.

When we levelled off, the Sim Instructor said "Wow...you got down in half the time of normal.......you're going to have to explain to me how you did that...."
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