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F-22
27th Apr 2002, 17:29
O.K. I'm confused here but what part of the plane preduces yaw I always thought it was the stabilizers. Cause I know what it is from like fighter jet games I've played But this is just what I think so if anyone could help me I'm just a little confused???


Thanx:confused:

PPRuNeUser0171
27th Apr 2002, 17:53
I'm no pilot so I'd welcome any corrections on this answer!!

It's my understanding that the yaw is produced by the rudder on the aircraft.

Yaw is used to help point the nose of the aircraft into the wind in certain crosswind conditions.

--
Gary Williams

Tinstaafl
27th Apr 2002, 19:22
For a start, don't rely on games to teach you aviation!

The basics:

An a/c has 3 axis, each at 90 deg to the other. These are the the 'Longitudinal', the 'Lateral' & the 'Normal'.

Each axis crosses the other two at the a/c's 'Centre of Gravity' (CG). The CG is the point where there is an equal mass in any direction.

Longitudinal Axis: Runs from nose to tail
Lateral Axis: Wingtip to wingtip
Normal: Vertically ie from below your bum to through the top of your head when you're seated in the a/c - presuming you're sitting at the CG of the a/c.


An a/c moves around each of these 3 axis. Think of each axis as an axle around which the airframe rotates.

Each movement around its axis has its own term, and a particular control surface to make the movement:

Pitch: movement around the lateral axis. You would see this as the nose of the a/c moving up & down. The control surface used are the 'Elevators' (there are usually two)

Roll: movement around the longitudinal axis. You would see this as one wing rising while the the other falls. The control surface used are the 'Ailerons' (again, there are two)

Yaw: movement around the normal axis. This is seen as the nose swinging to one side &/or the other. The control surface is the 'Rudder'.

Elevators are controlled by pushing or pulling the control column/joystick away or towards you. Pushing it away will lower pitch the nose down - presuming you're flying upright & not inverted! ;) , pulling it towards you will raise the nose.

Ailerons are controlled by rotating the control column as you would the steering wheel in a car. If the a/c has a joystick then you would move the stick from side to side. Rotate the column to the left/move the joystick to the left and the a/c will roll in that direction. Reverse that input and the a/c will roll in the opposite direction.

The rudder is controlled by the two pedals on the floor. Each pedal is joined to the other other in such a way that pushing one pedal forward forces the other pedal aft.

Push the left pedal forward & the a/c will yaw left. Push the right pedal & the a/c yaws right.

Moneyshot
29th Apr 2002, 13:59
Very good explanation. I agree that you should not learn aviation by playing games. The two are very different and whilst some might say that I myself am a fair to average aviator, I am absolutely appalling at some of the computer games around.
Also don't forget that yaw can be caused by the assymetry generated by the failure of a wing mounted engine. Also by a crosswind on the take-off or landing roll which will tend to weather-cock the aircraft into wind when it strikes the fin (vertical stabiliser).

Don D Cake
29th Apr 2002, 15:39
Pehaps I'm being a bit pedantic here but the rudder is used to control yaw not produce it. For instance you should use rudder in a turn to keep the aircraft balanced. You also use the rudder to control yaw during take off. There are occasions when you use the rudder to apply yaw in a controlled manner such as when sideslipping to reduce height or aligning the aircraft with the runway during a crosswind landing.