Is AD 97-21-08 a recurring Airworthiness Directive?

No — AD 97-21-08 is a one-time directive. Verify it was complied with in the aircraft's records.

Airworthiness Directive 97-21-08

Q: Which aircraft does AD 97-21-08 apply to?

AD 97-21-08 applies to General Electric — models CT58-110-1, CT58-110-2, CT58-140-1, CT58-140-2, T58-GE-3, T58-GE-5, T58-GE-8F, T58-GE-10. Serial/part conditions may narrow it to specific aircraft.

one-time

Official AD 97-21-08 · FR doc 97-27351 · 1997-10-20 · turboshaft engine

Airworthiness Directives; General Electric Company CT58 Series Turboshaft Engines

What this AD requires

This amendment adopts a new airworthiness directive (AD), applicable to General Electric Company CT58 series turboshaft engines, that requires removal from service of certain stage 1 and 2 forward cooling plates, and stage 2 aft cooling plates, and replacement with serviceable parts. This amendment is prompted by reports of certain cooling plates forged with contaminated alloy that could reduce the lives of the parts. The actions specified by this AD are intended to prevent cooling plate fracture, which could result in a contained engine failure, and an inflight engine shutdown.

Which aircraft AD 97-21-08 applies to

MakesGeneral Electric

ModelsCT58-110-1, CT58-110-2, CT58-140-1, CT58-140-2, T58-GE-3, T58-GE-5, T58-GE-8F, T58-GE-10, T58-GE-100, CT58, T58

Part-conditional — 37C300055P101, 3000T88P02, 3002T27P01.

Applies only to engines with stage 1 forward cooling plate P/N 37C300055P101, stage 2 forward cooling plate P/N 3000T88P02, and stage 2 aft cooling plate P/N 3002T27P01 installed.

Whether AD 97-21-08 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 97-21-08 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.