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Need tapered prop flange plate


Well-Known Member
May 29, 2010
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I need the front prop plate used on a tapered crankshaft. This is the one that goes on the front of the prop and the bolt heads rest on. Parts book calls for a P/N 3991.


New Member
May 31, 2011
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Classic Aero LLC 480-650-0883 has FAA approved drawings and data to produce those hubs for the tapered cranks.

also has flange plates

They often crack at the key way, and from over-tightening of the center nut, or the bend in propeller contact with the ground or other hard objects.

They did a run of hubs in 1997, and are doing another group of hubs now (June 2011). These are approved and delivered pursuant to FAR 21.303b with release paperwork for your airplane installation.

Check with Doug or Donna, or visit www.luscombe.org where they list them.

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