Is AD 2012-18-17 a recurring Airworthiness Directive?

Yes — AD 2012-18-17 requires a repetitive inspection. Next-due depends on the aircraft's time in service.

Airworthiness Directive 2012-18-17

Q: Which aircraft does AD 2012-18-17 apply to?

AD 2012-18-17 applies to Pratt & Whitney Division — models PW4052, PW4056, PW4060, PW4062, PW4062A, PW4152, PW4156A, PW4158. Serial/part conditions may narrow it to specific aircraft.

recurring

Official AD 2012-18-17 · FR doc 2012-22534 · 2012-09-17 · turbine engine

Airworthiness Directives; Pratt & Whitney Division Turbofan Engines

What this AD requires

We are superseding an existing airworthiness directive (AD) for all Pratt & Whitney Division (Pratt & Whitney) PW4052, PW4056, PW4060, PW4062, PW4062A, PW4074, PW4077, PW4077D, PW4084D, PW4090, PW4090-3, PW4152, PW4156A, PW4158, PW4164, PW4168, PW4168A, PW4460, and PW4462 turbofan engines. That AD currently requires initial and repetitive fluorescent penetrant inspections (FPI) for cracks in the blade loading and locking slots of the high-pressure compressor (HPC) drum rotor disk assembly rear drum. This new AD requires the same actions, requires replacement of the 13th, 14th, and 15th stage HPC seals with redesigned HPC seals as an additional action, and adds an optional terminating action to the repetitive inspection requirements by allowing replacement of the entire HPC drum rotor disk assembly with a redesigned HPC drum rotor disk assembly. This AD was prompted by Pratt & Whitney developing a redesigned HPC drum rotor disk assembly for certain affected engine models. We are issuing this AD to prevent failure of the HPC drum rotor disk assembly, which could lead to an uncontained engine failure, and 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 2012-18-17 applies to

MakesPratt & Whitney Division

ModelsPW4052, PW4056, PW4060, PW4062, PW4062A, PW4152, PW4156A, PW4158, PW4460, PW4462, PW4164, PW4168, PW4168A, PW4074, PW4077, PW4077D, PW4084D, PW4090, PW4090-3, PW4000

Part-conditional — 50H936, 50H936-002, 53H923-01, 53H923-001, 53H973-01, 53H973-001, 54H803-01, 54H803-001.

Applies only when a high-pressure compressor (HPC) drum rotor disk assembly with one of the listed part numbers (Table 1) is installed; affected P/N set varies by engine model group (PW4000-94in, PW4000-100in, PW4000-112in).

Whether AD 2012-18-17 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 2012-18-17 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.