Hello My name is Eruna.
I am using the translation system
because I am not good at English at the Japanese.
It thought about a peculiar character to the helicopter as follows.
Though it is uneasy because whether it is translated well is not understood….
http://clamp-cc.sakura.ne.jp/heli-r001.html#heli-r001-e
[Point of content of explanation]
Phenomenon to cause nose raising when helicopter advances.
It is a difference of the action point of the working gravity. the lift and the airframe of the rotor
This phenomenon
It is confirmed with [my RC helicopter] and [CSM3in1]
[Jetcopter 2nd (flight simulator of a real machine)].
[Real Flight]
Addition of photograph and great correction of misprint
P.S.
Excuse me, in Japanese
The expression might serve as a reference.
It is helicopter engineering. (Japanese)
http://kenm.k-server.org/hm.html