It was an guesstimate. I guessed that the hub was twice the mass of a propeller blade. There are 5 blades, so 5 blades plus the guess of the hub being equivalent to 2 blades is 7. However, this is only a guesstimate and could well be very inaccurate. The point of the video was to illustrate how large the centrifugal force can be.
Sir, what about the centripetal force? I thought that we can only use the centripetal force when we draw FBD and express external force? can you help me please?
awesome vid! why would you say spins maneuvers in a turboprop are prohibited below certain altitude where the air is denser and the idle power managed by the computer is less Np than at higher altitudes??? I think it is related to this theory of centripetal force and denser air (aka more push on the blades?) basically what happens if you put the prop at a reduced rpm and in a spin maneuver?
I’d say that spins are prohibited below certain altitudes because in a spin an aircraft can loose altitude very fast. After 3 full rotations the aircraft could lose 3000ft. This doesn’t give pilots much time to recover if they start at a low altitude. My personal recollection in an SF260 SIAI Marchetti during a test flight was that the pilot initiated spin recovery after the third full rotation and when we pulled out of the spin we had lost 3000ft. This was over 25 years ago so don’t hold me those numbers.
@@RoddyMcNamee Thank you Roddy for the input. yes definitely altitude to recover is a factor but in some Hetzel blade props and engines like in the PT6 in prohibited due to forces on the prop I think it has to be with the more dense air, centripetal force ..? what do you think (from the load and force perspective)
