Disclaimer: Any advice or information presented here is the opinion of the Author. It is not FAA approved or acceptable data, nor is it an authorization to perform maintenance or determine airworthiness.
Over the 7 years I have been working on Robbies, I’ve been asked this question quite a lot. Honestly, I’d bet that I’ve been asked about the 12 year life limit on M/R and T/R blades 100+ times. I have wrangled with owners about what can and cannot be done and what is and is not legal. I’ve been pigeonholed into having owners try to get me to sign off annuals “just so they could get a few more hours” out of a set of blades. So let’s break it down.
I’m just as cheap as anyone. I don’t want to replace something that doesn’t need to be replaced, nor do I want to fix things that aren’t broken. If I had to toot my own horn as an A&P, I’d say that I work on the owners behalf as much as possible. I don’t try to bill loads of shop hours or sell them parts they don’t need, often to the detriment of my own pocketbook. I have had owners actually get mad at ME for telling them that yes, indeed the life limited components section of the maintenance manual is legally binding. “I didn’t hold a gun to your head and make you buy a helicopter” was my response to the last angry owner that yelled at me over this.
- The life limited components pages of the maintenance manual are FAA approved and therefore must be complied with to stay legal.
- FAR 43 performance requirements for 100 hour and Annual inspections state that for rotorcraft, a manufacturers checklist must be used for portions of the inspection. Read FAR 43.15.
- The Robinson checklist also mentions life limits and overhaul requirements as well as all sorts of other items.
- An A&P or A&P IA must use a checklist when performing a 100 hour or Annual inspection. It can be of their own making, but not for a rotorcraft as per 43.15.
Based on the above facts, it can pretty easily be surmised that there are 2 methods which cannot really be gotten around on the blade life limit. You are required by the life limited components section, as well as by the required use of the manufacturers checklist at inspection time.
So, when does this 12 years start? That’s a good one right there as there are several different opinions out there floating around on this question. For the most part, the various opinions I have read recently are not true. Per the Robinson R22 maintenance manual section 3.002 blades installed at Robinson have an initial in-service date based on the date the Airworthiness certificate is issued. Calendar time for blades purchased as spares begins as of the date on the Authorized Release Certificate or 8130-3 tag. It would be wise for owners / pilots / technicians to get familiar with this idea before determining airworthiness. The R44 information is located in section 3.002 of the R44 maintenance manual and the R66 information is located in section 5-11 of the R66 maintenance manual.
Potential buyers beware, if the blades have been changed or supposedly have life remaining on them, you will need to make sure that the seller has the 8130’s available so that you can determine that they have life remaining. If you are unable to determine this, the blades are considered unairworthy. If you’re planning on pushing this limit or somehow coercing your local IA into continuing to perform annual inspections on the aircraft after these calendar limits have been exceeded I feel it would be good to let you know that yes, the IA in this case would be signing off an unairworthy aircraft, but also that the owner and the pilot would be violating FAR 91.7 Civil Aircraft Airworthiness in the event that they fly the aircraft. Sure, the blades will probably be fine, but if you’re planning on flying past life limits, why even bother with inspections at all?
I know this is a touchy topic with Robbie owners. Let’s not have any comments about how they could improve their blades etc…. Of course Robinson could build a different blade, but based on the relatively low cost of a Robinson and the relatively low cost of a set of blades, it would seem to me that opening yourself up to a potential lawsuit or certificate action by the FAA is just not worth the cost. Finally, of course the real cost here is flying parts within their limits so that we don’t hurt anyone.
Keep the whirly bits up – Johnny