I am now reading another book, I have some questions regarding drag, glide speed, spiral dive and flap.
1. The indicated airspeed for maximum L/D ratio is the speed for minimum drag and is very important because it is also the best glide speed (i.e., the speed for maximum gliding distance)
If best glide speed is the max L/D ratio, is this only happen on gliding but not cruising?
2. How the spiral dive can cause yawing descend?
I just can imagine it's performing rolling... maybe both yawing and rolling because Yawing can cause Rolling, and Rolling can cause Yawing....
3. "If the trust acts below the drag, then the increased thrust force will also tend to pitch the nose up"
I have no idea, hope someone can explain a bit..
4. Why lowering the flaps can result in changing of the aeroplane balance?
if Mean Camber Line is the average camber of the top and and btm surface of the aerofoil, then lowering the flag could increase the upper's surface's camber (arc)?
Is it because of this, the Centre of Lift move beyond the original one?
Hope someone can help! Thanks in advance.