An Analysis of the Gear Meshing Characteristics of the Main Planetary Gear Trains of Helicopters Undergoing Shafting Position Changes

Table 1

Gear parameters of the study planetary gear trains.

Gear	Num. of teeth	Outer module (mm)	Pressure angle (°)	Spiral angle (°)	Face width (mm)
Zs	62	8	20	0	300
Zr	83	8	20	0	320
Zc	228	8	20	0	350