Where to find information on weight breakdown for helicopters? I would be interested in information on the weight breakdown for the different components of a helicopter. How much of the maximum gross weight is related to the airframe, engine, gearboxes, transmissions, rotor systems, avionics, etc.

Could someone point me to a data source where i can find such information?

I already found a very reliable source on technical specification of helicopters in the Type Certificate Data Sheets published on the EASA website here:
EASA TCDS List
Helicopter Performance, Stability and Control by Ray Prouty has a section on weight estimates on page 663. A few of the equations, rest are in the book:



I'm afraid Mr. Prouty used imperial units.