Is AD 2012-18-15 a recurring Airworthiness Directive?

No — AD 2012-18-15 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2012-18-15 apply to?

AD 2012-18-15 applies to Bombardier — models DHC-8-400, DHC-8-401, DHC-8-402, DHC-8. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2012-18-15

one-time

Official AD 2012-18-15 · FR doc 2012-22335 · 2012-09-17 · airframe

Airworthiness Directives; Bombardier Inc. Airplanes

What this AD requires

We are adopting a new airworthiness directive (AD) for certain Bombardier Inc. Model DHC-8-400 series airplanes. This AD was prompted by reports that the automatic de-icing mode became unavailable due to a failure of the timer and monitor unit (TMU). This AD requires replacing the TMU. We are issuing this AD to prevent loss of the automatic de- icing mode and consequent increased workload for the flightcrew, which, depending on additional failures, could lead to loss of control of the airplane.

Which aircraft AD 2012-18-15 applies to

MakesBombardier

ModelsDHC-8-400, DHC-8-401, DHC-8-402, DHC-8

Serial-conditional — narrows to serials 4001–?.

Part-conditional — 4100S018-06.

Applies to serial number 4001 and subsequent, equipped with Aerazur timer and monitor unit (TMU) part number 4100S018-06.

Whether AD 2012-18-15 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 2012-18-15 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.