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Old 07-12-2010, 03:52 PM
JG27CaptStubing JG27CaptStubing is offline
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Quote:
Originally Posted by AndyJWest View Post
JG27CaptStubing, I see no reason why downthrottling would reduce turn radius, if you are already at best radius speed - again, I'd ask for evidence for this.
Fact: Reduced airspeed results in a smaller radius... Don't confuse Turn Rate with radius or compare it to Best Cornering Speed. Two different things.

The SR71 takes over 70+ miles to turn around when it was slowing for landing. That's also turning when it was at a very high Mach number. It's a gross example but I think you get the idea.

Quote:
Originally Posted by AndyJWest View Post
is just possible that downthrottling is temporarily helping the turn through a reduction in torque and in gyroscopic forces (though this shouldn't be a factor with a constant-speed prop), but I can't really see how. As I see it, the best turn rate at a given speed will otherwise be constant, regardless of power setting - all changing power does is determine whether the plane will accelerate or decelerate at that point in time. As has been pointed out, in the real world, extra power increases the local airspeed in the prop slipstream, which should help a little in high-power turns, but I doubt that IL-2 models this effect (we need to be careful about distinguishing between 'real-world' results and IL-2 ones, while discussing this subject).
Having a constant speed prop has nothing to do with Gyroscopic effects... Torque is reduced at a lower power setting and it does effect the turn but it's usually countered with rudder...

Power and elevator is used during a turn to make up for the loss of Vertical Lift Component. When you turn you're vectoring the vertical component of lift into the horizontal. You will need more lift to keep the plan level hence power and back pressure.

Remember airplanes can fly in various flight regimes.. You can be in different places in the power curve. Very high power low speed versus very high power high speed. You still have the same power setting but your in a different place in the curve.

The point in illustrating this is to show why there is so much confusion with some of these discussions.
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