The following is condensed from an article published in the Autumn edition of the GASCO Flight Safety Magazine.

Acknowledgements and thanks: GASCO/Gerry Humphreys

Loss of control is increasingly evident in fatal accidents in both GA and commercial operations, and the key to avoiding it is Angle of Attack Awareness.

For those wanting to learn to fly in as short a time as possible simulators are used to teach standard and emergency procedures, and to minimise costs. However, they do not recreate the effect of “G”, without which the trainee is missing out on experiencing instruction in an important skills area. Thus many trainees rarely get to fly a turn above 45angle of bank, or a pitch of 200.

AoA is important in determining whether a wing flies or not, so understanding it is vital if we are to understand what is happening when we pilot an aircraft. LIFT and DRAG are directly related to SPEED and AoA, but whereas we seem to concentrate on speed, AoA is the more fundamental concept to be grasped; because STALL is related to AoA alone. A good Instructor will thus introduce the concept of AoA at an early stage of training.

Primary Elevator effect:         
Stick back, AoA of wing increases, lift increases, aircraft climbs

Secondary Elevator effect:    
Stick back, AoA of wing increases, drag increases, speed decreases

Speed .v. AoA relationship:
High speed, Low AoA; Low speed, High AoA

Primary Aileron effect:
Change in the LOCAL AoA, which alters Lift and Drag in their own Area. Wing rises, 
Lift & Drag increase; Wing falls, Lift & Drag decrease

Secondary Aileron effect:
Yaw in the opposite direction to the input roll. In an established bank, an aircraft will first
slip then yaw in the same direction as the input roll, but at this stage the ailerons are actually
NEUTRAL. Any subsequent slip & yaw will be an effect of Angle of Bank & Stability, 
not aileron control input

Keep the ball in the middle:
If not, the ailerons will be deflected, with one wing at a higher AoA than the other.
Approaching a critical overall AoA, the down-deflected aileron will stall first

Spin training:
Of limited value in the real world, as most fatal spins occur too close to the ground to enable
recovery. Better to train prevention by means of realistic stall training incorporating AoA

Feeling the Force:
Much steep-turn training is done at 450 AoB, but training at 600 AoB as well is beneficial 
in two ways:
-     It demonstrates that the increased lift needed demands an increased AoA
      Stick back further = more lift = more drag  = more power required
-    The pilot can experience what 2G feels like, and if on pulling the stick back you feel 2G,
      you have enough lift to fly. You will not stall unless speed reduces, so given sufficient
      terrain clearance and the application of correct technique, recovery is achievable. If you
      don’t feel the force you need more speed or a lower AoA for the lift equation to work

Tony BirthComment