Ask Paul: What’s the proper procedure to cycle a prop?

Q: I’m curious about the procedure for cycling a constant speed propeller on run up. Three times seems to be a tradition, but I can’t find anything that supports this as a good habit. I’ve read that this was necessary with the big old props swung by a radial engine, but how about our newer, modern engines and props? What’s your recommendation on exercising a constant speed propeller?

JOHN BARRINGER, CFI, Salem, Oregon

A: John when it comes to the proper procedure of cycling the propeller, I’m afraid it’s out of my area. I will offer a suggestion as to where you should be able to get the information you’re looking for though, and I’m sure others may be seeking this information as well. This is one of those subjects that most people take for granted, so here might be a chance for all of us to learn something using my recommendation below.

My best guess would be to research the Pilot Operating Handbook, which is produced by the airframe manufacturer for the specific aircraft you are dealing with. This would be my first guess, but you may also be able to get some information from the specific propeller manufacturer.

I realize that most would think the engine manufacturer would be the proper source since it’s the engine’s oil pressure that causes the prop to function, but the real operation is caused by the propeller governor and what it causes to happen inside the propeller hub.

Paul McBride, an expert on engines, retired after almost 40 years with Lycoming. Send your questions to: [email protected].