AD 2001-25-02

final rule
Data completeness: 60%

Airworthiness Directives; Enstrom Helicopter Corporation Model TH-28 and 480 Helicopters

AD Number
2001-25-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 2001-SW-27-AD
FR Citation
66 FR 63915

Applicability

TypeManufacturerModelDetails
aircraft Enstrom Helicopter Corporation Model TH-28 and 480 Airworthiness Directives; Enstrom Helicopter Corporation Model TH-28 and 480 Helicopters

Unsafe Condition

Failure of a hub plate, loss of control of the main rotor, 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

Create a component history card or equivalent record for upper and lower hub plates (P/N 28-14280-1 and 28-14281-1). Determine and record total hours time-in-service (TIS). Replace hub plates with P/N 28-14280-3/28-14281-3 or P/N 28-14280-5/28-14281-5 depending on main rotor damper part numbers. Revise maintenance manual to establish 5000-hour TIS life limit.

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

Compliance Time

Within 30 days after the effective date (January 15, 2002).

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

Affected Aircraft

Enstrom Helicopter Corporation Model TH-28 and 480 helicopters with upper hub plate P/N 28-14280-1 and lower hub plate P/N 28-14281-1 installed.

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

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