Crikey those shots don't show the size of an ATP blade . The whole prop was about 16' in diameter , thus 1 blade should be about 7' long with hub approx 1' .
Don't forget there are 6 blades all plastic in that hub . Seem to remember prop rpm of approx 1050 ....perhaps climb setting ?
Sounded like a machine gun when prop deice used , ice being flung against fuselage . Bit quieter when sacrificial plates added to fuselage sides .
rgds condor.