Kieth, It would help very much if you read the posts and understand what is being said. As you say
you have demonstrated in your most recent post is the need to be very careful in composing posts to pprune threads
CARVE111 in his opening post asked (bolding mine)
From an engineering point of view," what are the advantages of a free power turbine over a fixed turbine engine when fitted to a helicopter"
Strike 1
I cannot think of a single free power trubine (sic) turboprop engine which has a freewheel unit or clutch
You are quite right, but when did the conversation turn to turbo prop. CARVE111 is talking helicopters (see above).
Strike 2
If you re-read all of the posts in this thread I think that you will also find that most contributors do not use your definition of clutch
If the contributors do not agree with the definition of a clutch as defined in my previous post they either need to get an education or explain in engineering turns what their definition is. I repeat the definition so that there is no misunderstanding. “Any of various devices for engaging and disengaging two working parts of a shaft or of a shaft and a driving mechanism.”
My reference to piston engine supercharge drive clutches was in response to wobble2plank’s post and his idea that a clutch was progressive in nature. In the supercharger drive applications mentioned there is no control over the engagement and so dramatic was the response in the P-51 that it was known to unnerved inexperienced pilots.
Most bicycle rear wheels contain a freewheel unit, but most people would never call it a clutch.
Most people don't because they don't probably bother to understand the underlying principles of operation, but I can assure you they do indeed contain a clutch (talking coaster hubs here. Made in Birmingham by Perry).
From
http://en.wikipedia.org/wiki/Bicycle_brake_systems When such a hub is pedalled forwards, the sprocket drives a screw which forces a
clutch to move along the axle, driving the hub shell or gear assembly. When pedalling is reversed, the screw drives the
clutch in the opposite direction, forcing it either between two brake pads and pressing them against the shell, or into a split collar and expanding it against the shell.
Kieth – For the entertainment we are providing might I suggest we split the royalties 50/50. Will negotiate you a larger share should you desire.
PS Never did get a reply to my personal email
