AD 66-14-02
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Learjet Inc. | 23 | Airworthiness Directives; LEARJET Models 23 and 24 Airplanes |
| aircraft | Learjet Inc. | 24 | Airworthiness Directives; LEARJET Models 23 and 24 Airplanes |
Unsafe Condition
Windshield deicing alcohol cans may fail, and attitude indicators may be inoperative or insufficiently powered, leading to reduced visibility in icing conditions and inadequate flight instrument reliability.
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Required Actions
Remove windshield deicing alcohol cans on Model 23 airplanes. Limit affected Model 23 airplanes (excluding specified serial numbers) to day VFR conditions below 240 flight level until installing a separate-source powered attitude indicator. Modify electrical systems on specified Model 23 and Model 24 serial ranges per Lear Jet Engineering Change Records within 550 hours' time in service after AD effective date.
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Compliance Time
within 550 hours' time in service after the effective date of this AD
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Affected Aircraft
Learjet Inc. Models 23 and 24 airplanes: Model 23 all serial numbers except listed exceptions; Model 24 serial numbers 24-100 through 24-129
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Federal Register Abstract
Windshield Deicing Systems
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-14-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-14-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes Subject: Windshield Deicing Systems Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/01/1966 Make: Learjet Inc. Model: 23 | 24 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 66-14-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-242 AD NUMBER: 66-14-02 SUBJECT HEADING: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes ACTION: SUMMARY: DATES: Effective June 1, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-14-02 LEARJET: Amdt. 39-242 Part 39 Federal Register June 1, 1966. Applies to Models 23 and 24 Airplanes. Compliance required as indicated, unless already accomplished. (a) On Model 23 airplanes, before further flight remove windshield deicing alcohol cans. (b) On Model 23 airplanes, the following applies to all Serial Numbers except 003, 011, 016, 020, 024, 026, 033, 035, 039, 043, 044, 047, 050, 051, 062, 065A, 069, 070, 072, 073, 074, 075, 076, 077, 078, 079, 080, 081, 082, 083, 087, 090, 092, 093: further flight is limited to day VFR meteorological conditions and to flight levels below 240 until installation of an attitude indicator (gyro horizon) usable by the pilot and powered by a source separate from the airplane's primary electrical system. (c) Modify the electrical system on Model 23 airplanes, and on Model 24 airplanes S/N 24-100 through 24-129, in accordance with Lear Jet Engineering Change Record No. 340, 227, 230 or 233 (as applicable) or equivalent data approved by the Chief, Engineering and Manufacturing Branch, Central Region within the next 550 hours' time in service after the effective date of this AD. The affected airplanes and applicable data are as follows: (1) Serial Numbers 23-012 and 23-031, Engineering Change Record No. 340. (2) Serial Numbers 23-003 through 23-011, 23-013 through 23-030, and 23- 032 through 23-099, Engineering Change Record No. 340, 227, 230, 233. (3) Serial Numbers 24-100 through 24-129, Engineering Change Record No. 340. This directive effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated May 21, 1966. Revised August 4, 1966. Revised November 22, 1966. FOOTER:
Document Text
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AD Final Rules - DRS_66-14-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-14-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes Subject: Windshield Deicing Systems Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 06/01/1966 Make: Learjet Inc. Model: 23 | 24 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 66-14-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-242 AD NUMBER: 66-14-02 SUBJECT HEADING: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes ACTION: SUMMARY: DATES: Effective June 1, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-14-02 LEARJET: Amdt. 39-242 Part 39 Federal Register June 1, 1966. Applies to Models 23 and 24 Airplanes. Compliance required as indicated, unless already accomplished. (a) On Model 23 airplanes, before further flight remove windshield deicing alcohol cans. (b) On Model 23 airplanes, the following applies to all Serial Numbers except 003, 011, 016, 020, 024, 026, 033, 035, 039, 043, 044, 047, 050, 051, 062, 065A, 069, 070, 072, 073, 074, 075, 076, 077, 078, 079, 080, 081, 082, 083, 087, 090, 092, 093: further flight is limited to day VFR meteorological conditions and to flight levels below 240 until installation of an attitude indicator (gyro horizon) usable by the pilot and powered by a source separate from the airplane's primary electrical system. (c) Modify the electrical system on Model 23 airplanes, and on Model 24 airplanes S/N 24-100 through 24-129, in accordance with Lear Jet Engineering Change Record No. 340, 227, 230 or 233 (as applicable) or equivalent data approved by the Chief, Engineering and Manufacturing Branch, Central Region within the next 550 hours' time in service after the effective date of this AD. The affected airplanes and applicable data are as follows: (1) Serial Numbers 23-012 and 23-031, Engineering Change Record No. 340. (2) Serial Numbers 23-003 through 23-011, 23-013 through 23-030, and 23- 032 through 23-099, Engineering Change Record No. 340, 227, 230, 233. (3) Serial Numbers 24-100 through 24-129, Engineering Change Record No. 340. This directive effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated May 21, 1966. Revised August 4, 1966. Revised November 22, 1966. FOOTER:
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