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Old 6th October 2006 | 02:39
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outofwhack
 
Joined: Apr 2004
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From: ˙ǝqɐq ǝɯ ʇ,uıɐ ʇɐɥʇ 'sɔıʇɐqoɹǝɐ ɹoɟ uʍop ǝpısdn ǝɯɐu ɹıǝɥʇ ʇnd ǝɯos
Angle of attach for auto

[I meant attack !]

Do any engineering types amongst us know how many degrees of pitch the blades of a helicopter typcially have when the collective is bottomed.

Just a rough answer is fine. I guess its still 2 or 3 degrees positive but would like a little confirmation.

I am returning to flying model helicopters as well as full size and would like to master the art of autorotations with models [to save me a few quid if engine stops].

Many in the model fraternity seem convinced you have to have actual negative pitch but every vector diagram I have studied for fullsize shows some amount of positive pitch in the simplified diagrams [that neglect washout etc].
For interest and from my own observations it appears model helicopters use a range of 5 to 9 degrees for hover and max power.

OOW
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