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Hartzell Propeller AD94-17-13

September 2010

Hartzell Propeller Airworthy Directive (AD) 94-17-13, amendment number 39-9008 was issued on 9-15-94. The recurring portion of this AD can be very confusing. It is recommended that you read it in its entirety in order to understand its full meaning. It basically deals with two different categories of aircraft: agricultural and certain Piper, Cessna and Gulfstream with (L)TIO-540 series engines installed.

The AD covers the following basic propeller model numbers within serial number range:

  • PHC-C3YF-1R( ) EE1 - EE1461
  • PHC-J3YF-1R( ) FP1 - FP37
  • PHC-L3YF-1R( ) FD1 - FD7
  • HC-C3YF-1R( ) EC1 - EC1020
  • HC-C3YK-1( ) CT1 - CT101
  • HC-C3YK-1R( ) or HC-C3YR-1R( ) DY1 - DY1897
  • HC-C3YK-2( ) or HC-C3YR-2( ) CK1 - CK3510
  • HC-C3YK-4( ) or HC-C3YR-4( ) EL1 - EL67
  • HC-E3YK-1( ) or HC-E3YR-1( ) FM1 - FM487
  • HC-E3YK-2( ) or HC-E3YR-2( ) DF1 - DF79
  • HC-E3YK-2A( ) or HC-E3YR-2A( ) DJ - DJ7787
  • HC-F3YK-2( ) or HC-F3YR-2( ) DA1 - DA1586
  • HC-F3YK-1( ) or HC-F3YR-1( ) DB1 - DB137
  • HC-I3YK-2( ) or HC-I3YR-2( ) FS1 - FS50

Per paragraph C of the AD, if the zerk holes are chamfered during overhaul, the inspection intervals are extended to 400 hours from the original 50-hour requirement. At 400 hours, per Hartzell Service Bulletin (SB) 165E, issued 1-21-1994, internal inspections are required.

During the prop disassembly, there is an opportunity to perform a hub change that eliminates the recurring inspection, per paragraph D of the AD. The hub change also eliminates the AD per hub serial number.

To confuse things further, the recurring inspection intervals for Hartzell SB 165E do not line up with AD 94-17-13. SB 165E inspection intervals are 50 hours if the grease zerk holes are not chamfered and 100 hours internal inspection if they are. However, the AD trumps the SB.

If you need further detail or have any other propeller questions, please contact: