AD-47-21-10
Propeller Guide Pins

Category: navion, propeller, hartzell

Applicability:
Serial numbers NAV-4-2 Through NAV-4-1010 with Hartzell HC-12X20-1 Propellers.

Supersedes: Was mandatory note 9 of AD-782-3

Compliance: Accomplish not later than September 1, 1947

Procedure: The propeller control piston guide pins, Hartzell P/N A-11, require additional safetying in order to prevent loosening and subsequent loss of engine oil. This is accomplished by the installation of a 3/32-inch steel dowel through the guide pin.

NAA Field Service Bulletin No. 30 covers this rework.


AD-47-21-10