Is AD 98-20-18 a recurring Airworthiness Directive?

No — AD 98-20-18 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 98-20-18 apply to?

AD 98-20-18 applies to International Aero Engines — models V2500-A1, V2500. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 98-20-18

one-time

Official AD 98-20-18 · FR doc 98-30331 · 1998-11-13 · turbine engine

Airworthiness Directives; International Aero Engines (IAE) V2500- A1 Series Turbofan Engines

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 98-20-18 that was sent previously to all known U.S. owners and operators of International Aero Engines (IAE) V2500-A1 series turbofan engines by individual letters. This AD requires, prior to further flight, removal from service of affected high pressure turbine (HPT) disks, identified by part number and serial number in the applicability paragraph of this AD, and replacement with a serviceable part. This amendment is prompted by a report of an uncontained HPT disk failure. The actions specified by this AD are intended to prevent an HPT disk fracture, an uncontained engine failure, and damage to the aircraft.

Which aircraft AD 98-20-18 applies to

MakesInternational Aero Engines

ModelsV2500-A1, V2500

Serial-conditional — narrows to serials P100430–P100430, P100421–P100421, P100621–P100621, P100618–P100618, P100346–P100346, P100381–P100381.

Part-conditional — 2A1801, 2A1101, 2A0902.

Applies only to engines with high-pressure turbine (HPT) stage 1 disk P/N 2A1801 (S/Ns P100430, P100421, P100621, P100618), HPT stage 1 disk P/N 2A1101 (S/N P100346), or HPT stage 2 disk P/N 2A0902 (S/N P100381) installed.

Whether AD 98-20-18 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 98-20-18 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.