That argument has frequently been made, and has some merit. There is also the counter-argument of erring on the side of caution. Certainly a worthy area of discussion for a separate thread (perhaps under Ask the Mechanic).Skyranger wrote:It is a very ugly policy that makes no sense to me, and quite a few more skilled than me, to have as a blanket replacement time.
That is certainly my situation, Alex. As a commercial operator, I have to pay strict attention to airframe and engine manufacturer's recommendations as well as legal requirements. For the record, anything issued as a Safety Directive has the force of law (see FAR 91.417(a)(2); latest revision added the words "or safety directive" after "airworthiness directive".) If it's just a Service Bulletin (even if marked "mandatory"), it's really optional. That is the case with the Rotax rubber replacement -- unless the airframe manufacturer issues a Safety Directive requiring compliance with that particular Rotax service bulletin. (Yes, they can do that.)perhaps your situation of running a flight school, or something the aircraft manufacturer throws in the pot, boxes you in firmly on that?
So much for legalities. Now, from a practical standpoint, if Rotax or the airframe manufacturer issues a service bulletin and it's marked "Mandatory," and a customer of mine has an accident in my plane, and sues, you can be sure plaintiff's attorney would be happy to tell the jury about and "Mandatory service bulletin" with which I had not complied. FARs notwithstanding, that would be damning evidence. Many FBOs would choose not to comply; I am more risk-averse. Rubber hoses cost less than compensatory and punitive damages in the event of a lawsuit.