Zami,
The answer is in the R66 brochure on the Robbie website.
TIME-BETWEEN-OVERHAUL (TBO)
is 2000 hours or 12 years for the airframe and 2000 hours or 3000 start cycles for the engine, whichever occurs first. All life limited components have approved service lives of at least 2000 hours.
http://www.robinsonheli.com/brochure...e_brochure.pdf
I have a R44 II and am considering upgrading to a R66, because I want to take 4 adults (including me), 2 sets of golf sticks and overnight bags. The numbers work on paper...I have flown the 66 briefly (15 minutes) and it is very nice. My intention is to get my endorsement next week which will give me more flight time to make the decision, however from what I have read here, it all sounds great.
Arrrj 