Wiffle tree
 

What is it?

To: Magnet

The most common application of a wiffeltree is on a wagon that is drawn by two horses.

It is a bar that pivots at the center and is attached to a draw bar which is in turn attached to the wagon. The horses are usually attached to the wiffeltree and actually push against it and cause the wagon to move forward. If one horse walks faster or exerts more force than the other horse the bar will pivot and the forces will balance out. There is a variartion of this and it is called a double tree and is used when four horses are in the hitch. It is also used in some aircraft flight control systems. I know it was used in the S-58 tail roitor servo and, I believe it is used in the CH47 flight control system.

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The Cat

...and on a BAC1-11?

As an apprentice I often heard it mentioned when talking about BAC1-11 stabs/elevators. Never managed to find out what it did though!

From what I can remember, the wiffle tree on the 1-11 was a part of the rudder feel system and was inclined to topple during taxying. A mod was introduced later to inhibit the fail light unless the wiffle tree had toppled for more than five seconds.

Ahhhhhhhh! the ol' one-eleven (descends into a bout of nostalgia, remembering the pink airplanes in the mid seventies)

I can recall a wiffletree in the Cessna nose wheel steering mechanism .... from memory it was a bellcrank type arrangement with a centre pivot point and a 'lug' either side for the steering cables.


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sprocket: .. No standards? Nooo problems!

[This message has been edited by sprocket (edited 28 December 2000).]