Is AD 98-27121 a recurring Airworthiness Directive?

No — AD 98-27121 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 98-27121 apply to?

AD 98-27121 applies to Raytheon — models 1900, 1900C, 1900D. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 98-27121

one-time

AD 98-27121 · 1998-10-15 · airframe

Airworthiness Directives; Raytheon Aircraft Company Models 1900, 1900C, and 1900D Airplanes

What this AD requires

This amendment supersedes Airworthiness Directive (AD) 97-04- 02, which currently requires installing new exterior placards with operating instructions for the airstair door, cargo door, and emergency exits, as applicable, on certain Raytheon Aircraft Company (Raytheon) Models 1900, 1900C, and 1900D airplanes. This AD requires either modifying the existing exterior placards with door operating instructions installed in accordance with AD 97-04-02; or installing new exterior placards with operating instructions for the airstair door, cargo door, and emergency exits, as applicable. This AD results from reports of the placards (required by AD 97-04-02) covering the atmospheric vents for the cabin door differential pressure lock. The actions specified by this AD are intended to continue to assure that clear and complete operating instructions are visible for opening the airstair door, cargo door, or emergency exits, and to prevent improper operation of the cabin door differential pressure lock caused by the placards blocking the atmospheric vents.

Which aircraft AD 98-27121 applies to

MakesRaytheon

Models1900, 1900C, 1900D

certain

Whether AD 98-27121 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 98-27121 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.