71-21-09 HARTZELL PROPELLERS: Amdt. 39-1313 as amended by Amendment 39- 1466. Applies to Models HC-E2YK-2RB, HC-E2YR-2RB, and HC-E2YL-2( ) Propellers equipped with 8465-7R, 7663-4, or J7663-4 noncounterweighted type blades.
Compliance required as indicated, unless already accomplished.
To prevent overspeeds in flight due to inadvertent loss of the propeller's air charge, accomplish the following:
(a) Propellers with 900 hours or more time in service since new or last overhaul as of the effective date of this AD, must be modified in accordance with paragraph (c) within the next 100 hours' time in service.
(b) Propellers with 900 hours or more time in service since new or last overhaul as of the effective date of this AD must be modified in accordance with paragraph (c) prior to the accumulation of 1,000 hours in service since new, or last overhaul.
(c) Install appropriate Spring Backup Kit and the propeller in accordance with Hartzell Service Letter No. 62dated June 23, 1970, revised August 6, 1970, or subsequent FAA- approved revision. An equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region
Amendment 39-1313 was effective November 14, 1971.
This amendment 39-1466 is effective June 27, 1972.