CX524,
Not specifically transmission, or even S76, but might be a usefull filler:
http://www.b-domke.de/AviationImages....html#Sikorsky
Some details, but no pics here:
http://www.sikorsky.com/details/0,96...ETI266,00.html
Type "transmission" in here to get tantalising taster (which doesn't work):
http://www.sikorsky.com/SearchIt/advquery.asp
Small photo here from general google search:
http://www.acrohelipro.com/pdfs/services/s76.pdf
Some details of active mount system (not sure if it is in service):
http://www.cds.caltech.edu/~macmardg/pubs/ahs_98.pdf
Recent patent to improve hobbing process for S76 gears:
http://www.patentstorm.us/patents/69...scription.html
Mart