by Gerado Arellano
(Chihuahua, Mexico)
The aircraft maintenance manual chapter 5 refers to McCauley Service Bulletin SB137AC for recommended overhaul times. The time between overhaul (TBO) of a McCauley model SAF32C93 propeller is 1,500 hours or 60 months.
If I am operating under FAR Part 91, must I follow the instruction of this service bulletin?
ANSWER: Even though most service bulletins are not mandatory, when they relate to recommended overhaul periods you should consider following those recommendations.
It has been determined by the manufacturer that these intervals will maintain continued airworthiness of the propeller.
Another thing to consider is your insurance on the aircraft. If the manufacturer recommends a specified overhaul time and you didn't follow that recommendation, your insurance could become invalid.