66-03-01 BRISTOL SIDDELEY: Amdt. 39-186 Part 39 Federal Register January 28, 1966. Applies to de Havilland Model Gipsy Queen Series 30 Engines With Crankshafts With Modification 2036 or 2162 Installed.
Compliance required as indicated.
To prevent further failures of the crankshaft front end that could result in loss of the propeller, accomplish the following:
(a) Unless already accomplished within the last 375 hours' time in service, inspect crankshaft for cracks within the next 25 hours' time in service after the effective date of this AD in accordance with Bristol Siddeley Technical News Sheet (TNS) GQ30 No. 70, dated November 16, 1965, or later ARB-approved issue, or an FAA- approved equivalent, and thereafter at intervals not to exceed 400 hours' time in service from the last inspection until modified in accordance with (c).
(b) Replace cracked crankshafts before further flight with an uncracked crankshaft.
(c) Incorporate Modification 2925 (which introduces shot peening underneath the chrome to improve the fatigue strength) on crankshaft within the next 1,600 hours' time in service after the effective date of this AD unless already accomplished.
This directive effective January 28, 1966.