Is AD 2008-22-53 a recurring Airworthiness Directive?

No — AD 2008-22-53 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2008-22-53 apply to?

AD 2008-22-53 applies to Md Helicopters — models MD900. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2008-22-53

one-time

Official AD 2008-22-53 · FR doc E8-28347 · 2008-12-02 · airframe

Airworthiness Directives; MD Helicopters, Inc. Model MD900 Helicopters

What this AD requires

This document supersedes AD 2008-18-52 and publishes in the Federal Register an amendment adopting Emergency Airworthiness Directive (AD) 2008-22-53 which was sent previously to all known U.S. owners and operators of MD Helicopters, Inc. (MDHI) Model MD900 helicopters by individual letters. This AD requires turning ON both Vertical Stabilizer Control System (VSCS) switches and turning OFF the autopilot (AP/SAS) switch; pulling certain AP/SAS circuit breakers; installing a placard near the AP/SAS master switch; installing an airspeed limitation placard on the instrument panel; and making changes to the Rotorcraft Flight Manual (RFM). This AD is prompted by 4 occurrences in which the left VSCS adapter tubes failed on the MD900 helicopters and the vertical stabilizer became uncontrollable, resulting in reduced yaw control of the helicopter. There were no injuries, but in one occurrence, due to the high speed quick yaw, the helicopter lost a window and a door. The actions specified by this AD are intended to prevent loss of yaw control and subsequent loss of control of the helicopter.

Which aircraft AD 2008-22-53 applies to

MakesMd Helicopters

ModelsMD900

Part-conditional — 500N7218-1.

Applies only when a Vertical Stabilizer Control System (VSCS) adapter tube, part number 500N7218-1, is installed.

Whether AD 2008-22-53 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 2008-22-53 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.