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Adverse yaw
Chao
Topic Author
Chao created the topic: Adverse yaw
Hi Bob/Rich,
Just enquire about a question of yaw.
As you can see in the pic, it is talking about roll and yaw. But recently I have read some else about adverse yaw. For example, if the airplane is rolling clockwise (from the pilot point of view), the airplane yaws to the left But in the your book, it said that the airplane yaws to right. Could you explain that for me, please?
There are two separate things happening here. I suggest you grab a model aircraft as you read this.
1. An aircraft that has banked to the right of its own accord, due to the pilot's inattention or because the pilot has lost visual reference in cloud, will begin to side slip to the right because the lift can no longer support the weight. The relative airflow coming from the right hits the fin and rudder and other keel surfaces and produces a yaw to the right. In this case, the pilot never did use the ailerons and if left unchecked, it will result in a spiral dive.
2. In the second case, the pilot applies aileron to deliberately cause the aircraft to roll to the right. Because the aileron on the left goes down and produces increased lift and drag, the left wing is pulled backwards producing a yaw to the left. This effect is called 'aileron drag' or 'aileron yaw' or sometimes 'adverse yaw'. It has been designed out of most modern aircraft by the use of differential or Frise ailerons and is often hardly noticed. It is the result of uneven drag on the ailerons.