Is AD 01-1661 a recurring Airworthiness Directive?

No — AD 01-1661 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 01-1661 apply to?

AD 01-1661 applies to Construcciones Aeronauticas, S.A. (Casa) — models CN-235, CN-235-100, CN-235-200. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 01-1661

one-time

AD 01-1661 · 2001-01-24 · airframe

Airworthiness Directives; Construcciones Aeronauticas, S.A. (CASA), Model CN-235, CN-235-100, and CN-235-200 Series Airplanes

What this AD requires

This amendment adopts a new airworthiness directive (AD), applicable to to all CASA Model CN-235, CN-235-100, and CN-235-200 series airplanes, that requires replacing the upper brackets in frames 33, 34, and 35, with improved brackets that are more fatigue resistant, and reinforcing frame 35. The actions specified by this AD are intended to prevent fatigue cracking in the zone of the fittings connecting the fuselage to stiffener rods located in frames 33, 34, and 35, which could result in reduced structural integrity of the airplane. This action is intended to address the identified unsafe condition.

Which aircraft AD 01-1661 applies to

MakesConstrucciones Aeronauticas, S.A. (Casa)

ModelsCN-235, CN-235-100, CN-235-200

applicability derived from the AD summary — confirm the model/serial from the records

Whether AD 01-1661 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 01-1661 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.