In helicopter applications, the two-piece gear is typically joined by welding, bolts, or splines. In the case of the U.S. Army CH-47D Chinook helicopter, a decision was made to eliminate these joints through the use of integral design. Integral shaft
spiral bevel gears must be designed such that the shaft does not interfere with gear tooth cutting and grinding. This paper discusses techniques to iterate in the design stage before
manufacturing begins.