Is AD 51-07-01 a recurring Airworthiness Directive?

No — AD 51-07-01 is a one-time directive. Verify it was complied with in the aircraft's records.

Airworthiness Directive 51-07-01

Q: Which aircraft does AD 51-07-01 apply to?

AD 51-07-01 applies to Sierra Hotel Aero, Inc. — models Navion (Army L-17A), Navion A (Army L-17B and L-17C), Navion B, Navion. Serial/part conditions may narrow it to specific aircraft.

one-time

AD 51-07-01 · 1951-01-01 · airframe

Airworthiness Directives; furnished by the Ryan Co. and must be installed by July 15, 1951. (Ryan Field Service Bulletin No. 9, dated September 1, 1950, cov

Which aircraft AD 51-07-01 applies to

MakesSierra Hotel Aero, Inc.

ModelsNavion (Army L-17A), Navion A (Army L-17B and L-17C), Navion B, Navion

Requires installation by July 15, 1951 of a part furnished by the Ryan Co.; corresponds to Ryan Field Service Bulletin No. 9, dated September 1, 1950.

Whether AD 51-07-01 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 51-07-01 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 →

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.