Almost lost prop

[Ron Lee]

What is "a little time"?

An hour? Overnight?

I usually give mine several hours or overnight. No basis other than gut feeling.

[Mel]

Originally Posted by Ron Lee

What is "a little time"?
An hour? Overnight?
I usually give mine several hours or overnight. No basis other than gut feeling.

My preference is to give them several hours at the very least. Overnight is good.

[Ron Lee]

I am not sure that I have seen guidance on humidity retorque as a function of exposure.

If going from a dry climate to a wet climate, where swelling may occur, after how many days in the humid climate should you retorque the prop.

I did it after about four days. No sound justification. Just preferred to be overcautious.

[WillyEyeBall]

After two months of down time for repairs, the first test flight with a new prop was a non event, but the grin factor almost overstressed the facial muscles. Boy, do I love these airplanes. As noted with other comments and incidents, the time between having any idea that something could be wrong and things going bad with a loose prop are pretty quick. We (my A&P mechanics, engine overhauler, prop manufacturers) are not certain a single cause can be determined, but the possibility of one or more of the bolts bottoming out, the 8 inch bolts through the spacer, and the 22 ft-pounds maximum torque recommended by the prop manufacturer were considered factors and possibilities. For the engine, the crank had to be replaced along with everything attached to the hub (starter ring, 2 ? inch extension, prop, crush plate, and spinner). After considering my type of flying and prop types, I decided to stick with wood, but go with an all maple one that has a proven record on aerobatic aircraft and the bolts are torqued to 35 ft-lbs for the prop. I have an extension that was recommended by the prop manufacturer that bolts to the hub, and the prop bolts to the extension. I?ve received conflicting opinions from highly experienced engineers and builders on whether the 8 inch bolts through the extension/spacer were a factor or not, but if the prop had been bolted to the extension, most likely the damage would have been limited to the extension and prop, and not the engine crank and hub. The sun is up, so I?m off to the airport to get my facial muscle exercise.