Toothed Belt PRU

[mohr]

I would like to know what would happen to the propeller if the toothed belt normally used in belt PRU it cut (due overload dynamic load/bad design).
Would the propeller be subject to overspeed?
Any help on this matter will be very welcome.
Cheers

[Frank Giger]

If the question is "what happens if the PSRU belt breaks," you've got it backwards.

The prop would loose all drive to it and windmill.

The engine would jump RPM's like mad, as it would no longer have any resistance from it by the prop.

Think of it as any other belt fed device attached to an engine. If a fan belt breaks on a car, the alternator doesn't speed up, it stops.