When discussing stresses at the blade root, it might be userful to know the forces involved.
I am pretty certain, comparing the acceleration I am able to impose on the aircraft when pulling by the prop with the acceleration on take-off, that the forces involved are one or two magnitudes lower than what the prop has been designed for [assuming I am pulling at the root].
Anyone around here who can caluclate
- the propeller thrust during take off
- the corresponding bending moment at the wing root
and compare this to the 100lbs and 3,000 lb in or so that I might be able to impose on the poor thing on a Sunday morning after a good breakfast?