PPRuNe Forums - View Single Post - Lift question
Thread: Lift question
View Single Post
Old 3rd April 2002 | 14:40
  #22 (permalink)  
englishal

 
Joined: May 2001
Posts: 4,729
Likes: 0
From: 75N 16E
If you slow down and keep pulling back maintaining altitude, you are increasing the AoA of the wing and hence the lift produced by the wing. Remember that the actual force-of-lift in Kg or N will not be as great becasue the reletive airflow is slower, but still just prior to stall the wing is producing maximum lift that it can (for that airspeed). So it is better to say that at whatever airspeed, the wing creates maximum lift at AoA just prior to stalling (roughly 16°). If the airflow is moving faster, the actual amount of lift in newtons or Kg will be more...but then this will be a pointless question as the 'amount of lift (in Kg)' will increase with airspeed indeffinitely (theoretically)

If you enter the stall by reducing power and attempting to maintain altitude, the lift will be equal to the weight just prior to the stall
This statement is true, but the wing is still producing the maximum possible lift based upon reletive airspeed.

It all boils down to AoA, or reletive airflow over the foil. If the yoke is yanked back at high speed, assuming the wings don't fall off then the AoA of the wing may exceed max, and the wing can stall even though the airspeed is high....This is why there is a manoeuvering speed or max abrupt control speed. Below this speed the wing will stall prior to causing structural damage, above this speed nothing is guaranteed !

Remember the aircraft can stall at any airspeed, and in any attitude.

Cheers
EA
englishal is offline