Is AD 98-20840 a recurring Airworthiness Directive?

Yes — AD 98-20840 requires a repetitive inspection. Next-due depends on the aircraft's time in service.

Which aircraft does AD 98-20840 apply to?

AD 98-20840 applies to British Aerospace — models 2, 3. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 98-20840

recurring

AD 98-20840 · 1998-08-07 · airframe

Airworthiness Directives; British Aerospace Model B.121 Series 1, 2, and 3 Airplanes

What this AD requires

This amendment adopts a new airworthiness directive (AD) that applies to certain British Aerospace Model B.121 Series 1, 2, and 3 airplanes. This AD requires installing an inspection opening in the area of the main spar web, repetitively inspecting the area at the main spar web for cracks, and repairing or replacing any cracked part. This AD also requires installing nuts of improved design at the wing to fuselage main-spar attachment fittings. This AD is the result of mandatory continuing airworthiness information (MCAI) issued by the airworthiness authority for the United Kingdom. The actions specified by this AD are intended to prevent structural failure of the main spar web area caused by fatigue cracking or separation of the wing caused by loose nuts at the wing to fuselage main-spar attachment fittings, which could result in loss of control of 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 98-20840 applies to

MakesBritish Aerospace

Models2, 3

certain

Whether AD 98-20840 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 98-20840 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.