Airworthiness Directive 97-25-10

recurring
Official AD 97-25-10 · FR doc 98-18649 · 1998-07-14 · turbine engine

Airworthiness Directives; Pratt & Whitney JT9D Series Turbofan Engines

What this AD requires

This amendment revises an existing airworthiness directive (AD), applicable to certain Pratt & Whitney (PW) JT9D series turbofan engines, that currently requires initial and repetitive fluorescent penetrant inspections (FPI) for cracks in cooling air holes of first stage high pressure turbine (HPT) disks, and replacement of cracked disks with serviceable parts. In addition, the current AD requires initial and repetitive FPI for cracks in tie bolt holes of certain other affected second stage HPT disks installed in PW JT9D series turbofan engines. This amendment calls out the second stage HPT hub assembly by part number (P/N) in addition to the hub P/N for clarification of affected parts, and references a service bulletin that does not change any of the requirements in the AD, but better explains the inspection procedures that are referenced in the current AD. This amendment also increases the repetitive inspection interval of first stage HPT disks. This amendment is prompted by the need to clarify the inspection procedures and the parts affected by this AD and by a re- evaluation of the risk analysis, based on new data from service, to establish a new repetitive inspection interval for the first stage HPT disk. The actions specified by this AD are intended to prevent turbine disk failure due to cooling air hole or tie bolt hole cracking, which could result in an uncontained engine failure and damage to the aircraft.

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 97-25-10 applies to

MakesPratt & Whitney
ModelsJT9D-59A, JT9D-70A, JT9D-7Q, JT9D-7Q3, JT9D-7R4D, JT9D-7R4D1, JT9D-7R4E, JT9D-7R4E1, JT9D

Also identified as (AI-500) series. Installed on but not limited to Airbus Industrie A300 and A310, Boeing 747 and 767, and McDonnell Douglas DC-10 series aircraft.

Whether AD 97-25-10 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 complianceThe specific action taken (inspected, replaced, modified) and to what revision.
DateWhen the work was done.
Aircraft timeTotal time in service / tach at compliance — how recurring next-due is computed.
Signature & certificateThe A&P/IA who returned it to service, with certificate number.
Is AD 97-25-10 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.