Is the "effective wing span" reduced in a turn? The Ace the technical pilot interview book says that in a bank the aircraft's lift is reduced due to an effective reduction in wing span. I know in a bank the vertical component of the lift vector is reduced due to the inclination of another component of lift towards the banked side. So the overall lift required to counter the weight is increased. That's why we need to increase the AOA or speed to maintain a level turn. But I am a bit confused about how the effective wing span is reduced, can anyone explain?
Your understanding is correct.
&quot;reduced effective wing span&quot; is just an analogy to help some people understand the concept of lift in a turn. The Total Lift is not reduced, it is just applied in a different vector in relation to gravity. The vertical lift component (in relation to gravity) is reduced and you can then imagine that the effective wingspan is also reduced by the same amount.
Banked turn (from Wikipedia)