PPRuNe Forums - View Single Post - Helicopter Dynamics: Gyroscopic Precession
Old 17th Mar 2014, 09:04
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AnFI - the classic example of servo transparency is on the Gazelle when experiencing jackstall - guess what? ....the Gazelle has symmetrical aerofoils.

The Lynx has two main aerofoil shapes along the length of the blade - a high camber section inboard and a reflex trailing edge further outboard - these combine to minimise the pitching moments caused by the use of non-symmetrical aerofoils. Guess what?...the Lynx doesn't suffer from servo transparency and is next to impossible to get into RBS.

Awblain - the conservation of AM is observed as changes in the RRPM as the blade flaps and the C of G of each blade moves towards or away from the rotor hub. The blades accelerate and decelerate constantly (hence the need for dragging hinges, which ISTR was the clever bit of Cierva's design).
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