Is AD 98-3921 a recurring Airworthiness Directive?

No — AD 98-3921 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 98-3921 apply to?

AD 98-3921 applies to Sabreliner — models 60, 70, 80. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 98-3921

one-time

AD 98-3921 · 1998-02-18 · airframe

Airworthiness Directives; Sabreliner Model 40, 60, 70, and 80 Series Airplanes

What this AD requires

This amendment adopts a new airworthiness directive (AD), applicable to certain Sabreliner Model 40, 60, 70, and 80 series airplanes, that requires revising the Airplane Flight Manual (AFM) to specify procedures that would prohibit flight in severe icing conditions (as determined by certain visual cues), limit or prohibit the use of various flight control devices while in severe icing conditions, and provide the flight crew with recognition cues for, and procedures for exiting from, severe icing conditions. This amendment is prompted by results of a review of the requirements for certification of the airplane in icing conditions, new information on the icing environment, and icing data provided currently to the flight crews. The actions specified by this AD are intended to minimize the potential hazards associated with operating the airplane in severe icing conditions by providing more clearly defined procedures and limitations associated with such conditions.

Which aircraft AD 98-3921 applies to

MakesSabreliner

Models60, 70, 80

certain

Whether AD 98-3921 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 98-3921 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.