AD 99-23-19

final rule
Data completeness: 70%

Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes

AD Number
99-23-19
Status
final_rule
Effective Date
Product Category
aircraft
Docket
99-NM-15-AD
FR Citation
Federal Register: November 16, 1999

Applicability

TypeManufacturerModelDetails
aircraft Learjet Inc. 31 Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes
aircraft Learjet Inc. 31A Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes
aircraft Learjet Inc. 35 Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes
aircraft Learjet Inc. 35A (C-21A) Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes
aircraft Learjet Inc. 60 Airworthiness Directives; Learjet Model 31, 31A, 35, 35A, and 60 Airplanes

Unsafe Condition

Failure of the spoiler actuator piston rod due to an incomplete heat treatment process, which could result in the spoiler panel floating and inducing an uncommanded roll of the airplane.

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

Required Actions

Perform a visual inspection to determine the serial number of the spoiler actuators using specified service bulletins. Replace the spoiler actuators with new ones before further flight if the serial number is listed in the service bulletins.

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

Compliance Time

Within 150 flight hours after the effective date of this AD

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

Affected Aircraft

Learjet Model 31, 31A, 35, 35A, and 60 airplanes with specific serial numbers as listed in the AD.

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

Source: Official FAA Source ↗

Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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