AD Amdt-39-11238

final rule
Data completeness: 70%

Airworthiness Directives; Learjet Model 23, 24, 25, 28, 29, 31, 55, and 60 Series Airplanes

AD Number
Amdt-39-11238
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. 98-NM-372-AD
FR Citation
64 FR 41778

Applicability

TypeManufacturerModelDetails
aircraft Learjet 23 Airworthiness Directives; Learjet Model 23, 24, 25, 28, 29, 31, 55, and 60 Series Airplanes

Unsafe Condition

A malfunction of the horizontal stabilizer anti-ice system could result in undetected accretion of ice on the leading edge of the horizontal stabilizer, leading to loss of pitch control and reduced controllability.

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

Required Actions

Inspect the electrical wire leads of the horizontal stabilizer anti-ice system to verify correct numbering. Install a wire ID strap on the left-and right-hand sides of each terminal block. Install a warning placard.

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

Learjet Model 23, 24, 25, 28, 29, 31, 55, and 60 series airplanes.

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.

View Official Source ↗ Find More ADs for Learjet 23

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final rule

Airworthiness Directives; Learjet Model 23, 24, 24A, 24B, 24B-A, 24C, 24D, 24D-A, 24E, 24F, 24F-A, 25, 25A, 25B, 25C, 25D, 25F, 28, 29, 31, 31A, 35, 35A (C-21A), 36, 36A, 55, 55B, and 55C Airplanes

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Airworthiness Directives; Learjet Model 23, 24, 24A, 24B, 24B-A, 24D, 24D-A, 24E, 24F, 25, 25A, 25B, 25C, 25D, and 25F Airplanes Modified by Supplemental Type Certificate SA1731SW, SA1669SW, or SA1670SW

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Effective: Dec 19, 2005 Category: aircraft

2005-16-09 Recurring

final rule

Airworthiness Directives; Learjet Model 23, 24, 25, 35, and 36 Airplanes

Unsafe Condition: The FAA is superseding an existing airworthiness directive (AD), which applies to certain Learjet Model 23, 24, 25, 35, and 36 airplanes. That AD currently requires repetitive inspections to detect...

Effective: Sep 13, 2005 Category: aircraft

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