Hurricane engine torque

[b101uk]

[QUOTE=Viper2000;270501] The reduction gear of the Merlin III is 0.477:1, so the prop rpm is about 1431.QUOTE]

the reduction gear is ~2.0964:1 to give an output of ~1431rpm from an input of 3000rpm.

0.477:1 would give an output ~6289.3rpm from an input of 3000rpm

You seam to have a habit of fudging your figures I.e. showing the correct result but the wrong equation ware RPM’s is concerned.

Also the torque at 3000rpm will be somewhat less than the torque available at peak torque rpm which will be at a lower rpm than rated power, hence why rpm’s fall lower than 3000rpm back towards peek torque rpm when a course pitch is selected.