Is AD 2011-21-07 a recurring Airworthiness Directive?

No — AD 2011-21-07 is a one-time directive. Verify it was complied with in the aircraft's records.

Airworthiness Directive 2011-21-07

Q: Which aircraft does AD 2011-21-07 apply to?

AD 2011-21-07 applies to Bombardier, Inc. — models CL-600-2B19, CL-600-2C10, CL-600-2D15, CL-600-2D24, CL-600. Serial/part conditions may narrow it to specific aircraft.

one-time

Official AD 2011-21-07 · FR doc 2012-26890 · 2012-11-13 · airframe

Airworthiness Directives; Bombardier, Inc. Airplanes

What this AD requires

We are revising an existing airworthiness directive (AD) for certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes; all Model CL-600-2C10 (Regional Jet Series 700, 701, & 702) airplanes; all Model CL-600-2D15 (Regional Jet Series 705) airplanes; and all Model CL-600-2D24 (Regional Jet Series 900) airplanes. That AD currently requires replacing certain water accumulator assemblies having a certain part installed on the pitot and static lines of the air data computer (ADC). This new AD corrects an erroneous service document number and removes the other erroneously cited service document from that AD. This new AD was prompted by an error that was discovered in one service document number, and a determination that credit for accomplishing actions in another erroneously cited service document should be removed from that AD. We are issuing this AD to prevent pitot-static tubing from becoming partially or completely blocked by water, which could result in erroneous airspeed and altitude indications and consequent loss of control of the airplane.

Which aircraft AD 2011-21-07 applies to

MakesBombardier, Inc.

ModelsCL-600-2B19, CL-600-2C10, CL-600-2D15, CL-600-2D24, CL-600

Serial-conditional — narrows to serials 7003–7067, 7069–7990, 8000–8107.

Serial-number gating (7003-7067, 7069-7990, and 8000-8107 and subsequent) applies only to Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes; all Model CL-600-2C10 (Series 700/701/702), CL-600-2D15 (Series 705), and CL-600-2D24 (Series 900) airplanes are covered without serial restriction.

Whether AD 2011-21-07 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 2011-21-07 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.