New Two blade head question

Stephen Toor

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Joined
Feb 10, 2005
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92
Location
Los Angeles CA
Now I searched really good this time before I popped my question out for all to see.

Hughes 500 and aerocopter both use tb or tt straps for flap and feathering, both are more than two blades.

Is there any reason why a one piece strap pack can not be used to replace the teeter head for two blade gyros and helicopters?

You would still have multiple straps stacked into the pack, a fixed hub that the straps would attach thru to the other blade. A pitch housing to feather the blades.

However you would have alot fewer parts, the blades would still flap and feather independent of each other though because the head would not teeter.

Could this work?
 
Stephen,

You need to go and study the functioning of a teetering head, vs an articulated head. You will then see you cannot simply uncouple the combined see-saw action of the 2 blades in a teetering head.

Teetering heads have see-saw, and need no lead-lag. The moment you start independently flapping, you need to introduce lead-lag. With lead-lag comes ground resonance, so now the landing gear design comes to play.

Simple system still stays, simple teetering, allowing you simple rigid skids.

Cheers,

Francois
 
OK, I see what you are getting at.

So on the Kaman heads that use servo flaps for twist the blade to change its pitch, I also see lead/lag hinges and dampners.............Why would they be needed since the head teaters also and the blades are coupled thru the seesaw action?

Unless it is to ease the vibrations due to the coupling caused by the delta angle in the teeter point on the head?


Help? Please? still learning and reading
 
So on the Kaman heads that use servo flaps for twist the blade to change its pitch, I also see lead/lag hinges and dampners.............Why would they be needed since the head teaters also and the blades are coupled thru the seesaw action?

Unless it is to ease the vibrations due to the coupling caused by the delta angle in the teeter point on the head?


Help? Please? still learning and reading


OTHER: Flight Dynamics - General - Lead-Flap Coupling, for Intermeshing Rotors (kpβ) & Pitch-Lag Coupling (δ2) ? (δ4)
 
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