AD 2020-19-04

final rule
Data completeness: 80%

Airworthiness Directives; Leonardo S.p.a. Helicopters

AD Number
2020-19-04
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2020-0554
FR Citation
85 FR 55781

Applicability

TypeManufacturerModelDetails
aircraft Leonardo S.p.a. Airworthiness Directives; Leonardo S.p.a. Helicopters

Unsafe Condition

defective duplex bearings on MGB input modules, due to a quality control issue, which could result in damage including corrosion and cracking, which could result in excessive heat of the input module duplex ball bearing inner race and subsequent loss of engine power and loss of helicopter control.

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

Required Actions

remove from service each MGB input module within 300 hours time-in-service (TIS) if the P/N and S/N of both MGB input modules are listed in paragraph (a) of this AD, or within 1,200 hours TIS if the P/N and S/N of only one MGB input module are listed in paragraph (a) of this AD, and do not install an MGB input module with a P/N and S/N listed in paragraph (a) of this AD on any helicopter after the effective date of this AD.

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

Compliance Time

Within 300 hours time-in-service (TIS) or within 1,200 hours TIS, depending on the condition of the MGB input modules.

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

Affected Aircraft

Leonardo S.p.a. Model AB139 and AW139 helicopters, certified in any category, with main gearbox (MGB) input module part number (P/N) 3K6320A00135 with serial number (S/N) KHI-200 or P/N 3K6320A00136 with an S/N listed in Table 1 to this paragraph installed.

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

Source: Official FAA Source ↗

Retrieved: Apr 4, 2026

Rights: U.S. Government Public Domain

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