AD 66-13-04
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
Failure of the pressure control static air system could result in improper cabin pressurization control, leading to loss of cabin pressure.
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Required Actions
Modify the pressure control static air system in accordance with Lear Service Kit SK23/24-230 or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region.
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Compliance Time
before further flight
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Affected Aircraft
Learjet Inc. Models 23 and 24 Airplanes
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Federal Register Abstract
Pressure Control Static Air System
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-13-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-13-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes Subject: Pressure Control Static Air System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/17/1966 Make: Learjet Inc. Model: 23 | 24 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 66-13-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-237 AD NUMBER: 66-13-04 SUBJECT HEADING: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes ACTION: SUMMARY: DATES: Effective May 17, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-13-04 LEARJET: Amdt. 39-237 Part 39 Federal Register May 17, 1966. Applies to Models 23 and 24 Airplanes. Compliance required before further flight, unless already accomplished, except that the airplane may be flown to a base where the repair can be performed, provided the following restrictions are contained on a placard in clear view of the pilot: "(a) No passengers may be carried. "(b) Monitor the cabin pressure indicator for proper pressurization control. If automatic and/or manual control of the cabin pressure is not properly effective: "(1) Turn air bleed off to shutoff bleed air. "(2) Reduce power to reduce bleed air pressure as necessary. "(3) Don oxygen masks. "(4) Expedite descent to a safe altitude." Modify the pressure control static air system in accordance with Lear Service Kit SK23/24-230 or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region. 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 10, 1966. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_66-13-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-13-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes Subject: Pressure Control Static Air System Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 05/17/1966 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: 66-13-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-237 AD NUMBER: 66-13-04 SUBJECT HEADING: Airworthiness Directives; LEARJET Models 23 and 24 Airplanes ACTION: SUMMARY: DATES: Effective May 17, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-13-04 LEARJET: Amdt. 39-237 Part 39 Federal Register May 17, 1966. Applies to Models 23 and 24 Airplanes. Compliance required before further flight, unless already accomplished, except that the airplane may be flown to a base where the repair can be performed, provided the following restrictions are contained on a placard in clear view of the pilot: "(a) No passengers may be carried. "(b) Monitor the cabin pressure indicator for proper pressurization control. If automatic and/or manual control of the cabin pressure is not properly effective: "(1) Turn air bleed off to shutoff bleed air. "(2) Reduce power to reduce bleed air pressure as necessary. "(3) Don oxygen masks. "(4) Expedite descent to a safe altitude." Modify the pressure control static air system in accordance with Lear Service Kit SK23/24-230 or an equivalent approved by the Chief, Engineering and Manufacturing Branch, FAA Central Region. 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 10, 1966. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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