Is AD 2001-25-51 a recurring Airworthiness Directive?

No — AD 2001-25-51 is a one-time directive. Verify it was complied with in the aircraft's records.

Which aircraft does AD 2001-25-51 apply to?

AD 2001-25-51 applies to Md Helicopters — models 900, 902. Serial/part conditions may narrow it to specific aircraft.

Airworthiness Directive 2001-25-51

one-time

Official AD 2001-25-51 · FR doc 02-1054 · 2002-01-17 · airframe

Airworthiness Directives; MD Helicopters, Inc. Model MD900 Helicopters

What this AD requires

This document publishes in the Federal Register an amendment adopting Airworthiness Directive (AD) 2001-25-51, 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 performing a dual power confirmation test on the Integrated Instrument Display System (IIDS) and inserting a revision to the Rotorcraft Flight Manual (RFM), as applicable. If the IIDS fails the power test, replacing it is required before further flight. Removing the temporary revision when the IIDS is replaced and inserting the applicable revision into the RFM is also required. This AD is prompted by the failure of the IIDS during a helicopter hover operation. The actions specified by this AD are intended to prevent total power failure of the IIDS and the subsequent inability to monitor information and warning indications essential for the operation of the helicopter.

Which aircraft AD 2001-25-51 applies to

MakesMd Helicopters

Models900, 902

Part-conditional — 900A3720002-107, 900A3720002-115, 900A3720002-111, 900A3720002-117, 900A3720002-109, 900A3720002-119, 900A3720002-113, 900A3720002-121.

IIDS dual power confirmation test per MDHI Service Bulletin SB900-081R1; models 900/902 (RFM CSP-900RFM-1, CSP-900ERFM-1, CSP-902RFM-1, CSP-902RFM207E-1); IIDS replaced with new P/N if it fails to continue operating after the power test.

Whether AD 2001-25-51 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 2001-25-51 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.