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jugent
12-08-2005, 04:48 AM
All single engine aircrafts yaw, it don€t fly straight according to its vertical axis, at least at some speed, I think. This must increase the drag.
It€s like tugging a boat in a rope when the rope isn€t connected to the very bowline.
If the rope is connected to the side of the bowline, the boat will not go straight according to its vertical axis.

The yaw is corrected by rudder, but many planes don€t fly straight when the yaw is corrected. This must be corrected with the ailerons.
To correct this most aircrafts got trim able ailerons, but not most German and Japanese fighters.
German fighters got the fixed tab correction, witch means that a bar on the ailerons and rudders where bent to give a straight line at "cruise speed".
Allied fighters got trim-tabs that corrected this.
I have noticed that German fighters bleed energy much more than allied fighters, is it so that the German planes yawed more than the USAF and RAF aircrafts?
Did the flight engineers of Allies and Axis-countries had different thoughts about the matter of yaw,

The yaw can be seen by an inclinometer on the flight indicator.
But I don€t understand this gauge.
How can this "ball" that, indicates gravity, indicate uncorrected vertical position, the incorrectness is by the vertical axis.
The Artificial horizon shows straight flight and the ball is not in the centre of the tube. Don€t they have to use a gyro-device to indicate yaw?

I hope that although my English is bad, some have understood the problem.

jugent
12-08-2005, 04:48 AM
All single engine aircrafts yaw, it don€t fly straight according to its vertical axis, at least at some speed, I think. This must increase the drag.
It€s like tugging a boat in a rope when the rope isn€t connected to the very bowline.
If the rope is connected to the side of the bowline, the boat will not go straight according to its vertical axis.

The yaw is corrected by rudder, but many planes don€t fly straight when the yaw is corrected. This must be corrected with the ailerons.
To correct this most aircrafts got trim able ailerons, but not most German and Japanese fighters.
German fighters got the fixed tab correction, witch means that a bar on the ailerons and rudders where bent to give a straight line at "cruise speed".
Allied fighters got trim-tabs that corrected this.
I have noticed that German fighters bleed energy much more than allied fighters, is it so that the German planes yawed more than the USAF and RAF aircrafts?
Did the flight engineers of Allies and Axis-countries had different thoughts about the matter of yaw,

The yaw can be seen by an inclinometer on the flight indicator.
But I don€t understand this gauge.
How can this "ball" that, indicates gravity, indicate uncorrected vertical position, the incorrectness is by the vertical axis.
The Artificial horizon shows straight flight and the ball is not in the centre of the tube. Don€t they have to use a gyro-device to indicate yaw?

I hope that although my English is bad, some have understood the problem.

Tully__
12-08-2005, 05:32 AM
The "ball" is just that, a ball in a tube. The tube is slightly curved and the ball rests at the bottom of the curve. It is filled with liquid to make the ball come to rest quickly after an attitude change.

When the aircraft is not co-ordinated in rudder (pointed somewhere other than where it's going) there is drag and turning force at an angle to the line of the fuselage. This force disturbs the ball from it's rest position in the centre of the tube, indicating to the pilot which direction he's incorrectly adjusted. Stepping on the rudder pedal on the same side as the ball will correct the deviation and recenter the ball.

To explain any clearer I'd need a force vector diagram