Is AD 99-25-05 a recurring Airworthiness Directive?

Yes — AD 99-25-05 requires a repetitive inspection. Next-due depends on the aircraft's time in service.

Which aircraft does AD 99-25-05 apply to?

AD 99-25-05 applies to Hartzell — models HD-E6C-3(), HD-E6C. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 99-25-05

recurring

Official AD 99-25-05 · FR doc 99-31172 · 1999-12-03 · propeller

Airworthiness Directives; Hartzell Propeller, Inc. Model HD-E6C- 3( ) Propellers

What this AD requires

This amendment adopts a new airworthiness directive (AD) that is applicable to Hartzell Propeller, Inc., Model HD-E6C-3( ) series propellers, installed on Fairchild Dornier 328-110 series and 328-120 series airplanes. This action supersedes telegraphic AD T99-06-51 that currently requires initial and repetitive inspections of the propeller hub for cracks or grease leaks, and replacement of the hub if any cracks are found. This amendment requires an initial and repetitive inspections of Hartzell propeller hub, part number (P/N) D-5108-1, for cracks or grease leaks, replacement of the hub if any cracks are found, and allows the installation of propeller hub, P/N D-5108-5, as a terminating action for the inspection requirements. This amendment is prompted by the addition of propeller hub P/N D-5108-5 as a terminating action for the inspection requirements and by the removal of the inspection requirements for Hartzell propeller hub, P/N D-5108-5. The actions specified by this AD are intended to prevent severe vibration due to cracks in the propeller hub that could result in propeller blade loss, loss of control, and possible damage to the airplane.

Repetitive inspection. Re-inspect. The next-due date/hours depend on this aircraft’s time in service — a records report computes it from the logbooks.

Which aircraft AD 99-25-05 applies to

MakesHartzell

ModelsHD-E6C-3(), HD-E6C

Part-conditional — D-5108-1.

Applies to Hartzell Model HD-E6C-3( ) series propellers with propeller hub part number D-5108-1. Applies to each propeller identified regardless of prior modification/alteration/repair in the affected area. Installed on but not limited to Fairchild Dornier 328-110 and 328-120 series airplanes.

Whether AD 99-25-05 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.

How AD compliance is recorded

A valid compliance record (14 CFR 43.9) states:

Method of compliance — The specific action taken (inspected, replaced, modified) and to what revision.

Date — When the work was done.

Aircraft time — Total time in service / tach at compliance — how recurring next-due is computed.

Signature & certificate — The A&P/IA who returned it to service, with certificate number.

Is AD 99-25-05 complied with on your aircraft?

Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.

Look up a tail number →Read the full directive (Federal Register)

Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.