Orval Fairbairn wrote in message .. .
This past Monday, a couple of my friends took off in a Bonanza with a
3-blade McCauley prop installed. At about 1000 feet, on power
reduction, one of the blades came unhooked from its pitch change
mechanism and went into "free pitch" mode.

There is a composite material link between the pitch change mechanism
and the blade acutator pin, which is on the circumference of the blade
shank. It's about 2" long.

This is a reason that McCauley specifically warns against pulling the
airplane with the prop while on the ground. If you pull on the back
edge of the blade, you can put enough torque on it to threaten the links.

Ond does wonder how they were cared for because this is a very rare
failure.

It would be like a terrible mistrack on a helicopter rotor.

Bill Hale BPPP Instructor