63-10-01 FAIRCHILD: Amdt. 563 Part 507 Federal Register May 7, 1963. Applies to all C-82A and C-82A Jet Packet Aircraft equipped with Pratt & Whitney R-2800 Military or Civil C, CA, or CB Series engines and Hamilton Standard 33E60/6491-0 or 33E60/6801-0 Propellers.
Compliance required as indicated.
Premature wear in the bushings in the original rear (heavyweight crankshaft vibration dampers in R-2800 "C" Series engines reduces crankshaft damping characteristics such as to cause propeller blade vibration stresses above the safe limit for continuous service. In addition, flight operation at grass weights in excess of 36,500 pounds with unmodified Hamilton Standard 6491-0 propeller blades installed, imposes blade vibration stresses above the safe limit for continuous service. To prevent propeller blade fatigue failures from these causes, the following modifications and engine operating limitations are required:
(a) On airplanes equipped withany of the engines specified herein, prior to 100 hours' time in service after the effective date of this AD, accomplish the following:
(1) Install the following placard on the instrument panel in full view of the pilot: "Avoid operation between 1,550 and 1,650 r.p.m."
(2) Apply red arc markings on the tachometers over this restricted speed range.
(b) On airplanes equipped with R-2800-C Series engines having the original C series type crankshaft with heavyweight front and rear vibration dampers accomplish one of the following within the next 300 hours' time in service after June 6, 1963, for engines which had 350 or more hours' time in service since new or overhaul on June 6, 1963, or prior to the accumulation of 650 hours' time in service since new or overhaul for engines which had less than 350 hours' time in service since new or overhaul on June 6, 1963:
(1) Replace the crankshaft assembly with crankshaft assembly, P/N 326054, in accordance with Pratt & Whitney Aircraft Service Bulletin No. 1687 dated April 22, 1958. Identify engines so modified by adding suffix letter " D" to the engine model designation on the nameplate.
(2) Replace present engines with engines incorporating the CA or CB type crankshaft. These engines are identified by the suffix letter H or D on the engine model designation on the nameplate.
(c) On 33E60/6491-0 propellers, prior to 300 propeller hours' time in service after the effective date of this AD, accomplish one of the following:
(1) Replace the 6491-0 propeller blades with 6801-0 blades.
(2) Replace present 6491-0 blades with 6491-0 blades which have had the blade shanks cold rolled and the inner portion of the blades shotpeened by Hamilton Standard or by a method approved by the FAA.
Note. - Hamilton Standard has advised that only blades which have had no time in service and which are in good condition otherwise, will be accepted for this rework.
(d) On 33E60/6491-0 or 33E60/6801-0 propellers, prior to 300 propeller hours' time in service after the effective date of this AD, the barrel bolt lugs on the 33E60 hubs shall be reworked and shotpeened and the inside of the barrel arms shotpeened in accordance with Detailed Instruction No. 6 of Hamilton Standard Bulletin No. 628 dated January 30, 1962.
(e) The propeller modifications specified in (c) and (d) are not required provided the operating limitations of this airplane are revised to limit the operating gross weight to 36,500 pounds and to limit the maximum takeoff power to 2,100 hp.
This directive effective June 6, 1963.
Revised January 27, 1965.