AD 2005-21-02

final rule
Data completeness: 70%

Airworthiness Directives; MD Helicopters, Inc. Model 369D, 369E, 369F, 369FF, 500N, and 600N Helicopters

AD Number
2005-21-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2004-SW-13-AD
FR Citation
70 FR 60206

Applicability

TypeManufacturerModelDetails
aircraft MD Various Airworthiness Directives; MD Helicopters, Inc. Model 369D, 369E, 369F, 369FF, 500N, and 600N Helicopters

Unsafe Condition

Fatigue cracking of the main rotor blade due to a higher number of torque events (TEs) than originally calculated, which could lead to blade failure and subsequent loss of control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect both surfaces of each main rotor blade using a 10X or higher magnifying glass to detect chord-wise cracks protruding from under the root fitting and doubler on the bottom-side of the blade. Replace any cracked blade with an airworthy blade. Determine and record the number of torque events (TEs) accumulated on each blade.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

MD Helicopters, Inc. Model 369D, 369E, 369F, 369FF, 500N, and 600N helicopters with certain part-numbered main rotor blades and modified with Supplemental Type Certificate (STC) No. SR09172RC, SR09074RC, or SR09184RC.

AI-generated summary from the source AD text. Verify against the official source before acting.

Source: Official FAA Source ↗

Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

This site is not affiliated with or endorsed by the FAA. Always verify with official sources.