81-13-05 DOWTY ROTOL: Amendment 39-4169. Applies to Dowty Rotol (c)R.289/3-110-F/1 and (c)R.289/3-110-F/11 propellers used on the WSK-Pezetel Model PZL-3S engine installed on but not limited to Gulfstream American (formerly Grumman) Model G-164A, B, C airplanes modified by STC SA2731SW, and Ayres (formerly Rockwell) Model S2R-R3S, and Model S2R airplanes modified by STC SA3897WE.
Compliance is required as indicated unless previously accomplished. To preclude the possibility of blade tip failures, accomplish the following:
Prior to each engine start or prior to accumulating 3 hours of engine/propeller operating time, whichever occurs first, using a 2x to 5x power magnifying glass, or equivalent, visually inspect for cracks, scratches, pitting, nicks, dents or gouges the outer 15 inches of the leading edge on propeller blades, P/N 660705335, in the area extending at least one inch on either side of the leading edge. No cracks or damage are permitted. Any blades with cracks must be replaced with an airworthy blade before further flight. All surface damage in the form of scratches, pitting, nicks, dents or gouges must be removed before further flight in accordance with Dowty Rotol Service Instructions or Section 3 of Advisory Circular 43.13-1A.
In addition, prior to accumulating 15 hours of engine/propeller operating time, using dye penetrant or equivalent, inspect the outer 15 inches of the leading edge of propeller blades, P/N 660705335, in the area extending at least one inch on either side of the leading edge for cracks and reinspect at least once every 15 operating hours thereafter. No cracks are permitted, and any blades with cracks must be replaced with an airworthy blade before further flight.
Upon request of the operator, an equivalent means of compliance with the requirement of this AD may be approved by the Chief, Engineering and Manufacturing Branch, FAA, Great Lakes Region.
This amendment becomes effective July 28, 1981, asto all persons except those to whom it was made immediately effective by the priority mail letter dated June 12, 1981, AD 81-13-05, which contained this amendment.