5 blades v 7 v 9

[Stuart Sutcliffe]

Originally Posted by Sleepybhudda

https://www.youtube.com/watch?v=0bP2MH3LqvI

Best documentary to easy explain props.

That video certainly brings back a memory from doing a QFI course at CFS, RAF Scampton in the early 1990s! As you say, it is a good summation of props. There is a piece about prop solidity starting around 14:08 into the presentation.