During a turn the nose goes down. Why ?
Hi,
If I start a coordinated turn with my airplane, the nose is automatically going down and I need to pull in the stick to maintain the nose on the horizon, thus level flight.
Why is that ?
This is NOT because of the increase in apparent weight (which is the vector sum of mv²/r + weight) because apparent weight applies at the Center of Gravity so its increased value does not affect the moment around the CG.
My hypothesis is that during the initial part of the turn I bank the aircraft. Then during the first seconds, a non symmetrical relative wind appears on the fin, generating a total reaction on the fin which is directed upwards and in the opposite direction of the turn. That aerodynamic reaction on the fin would create a moment nose down around the CG (and also a moment which will put the nose of the aircraft in the relative wind as a weather vane and re-establish a symmetrical airflow on each side of the longitudinal axis of the aircraft).
What do you think about that ?
Any other idea/opinion is more then welcome.