AD 76-21-01
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Lockheed Martin Corporation | L-1011-385-1 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-1-14 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-1-15 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
| aircraft | Lockheed Martin Corporation | L-1011-385-3 | LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes |
Unsafe Condition
Incorrect installation of latch pins on the latch fittings of the C-1A cargo door surround structure could result in a possible in-flight loss of the C-1A cargo door.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Install latch pin guard assemblies and related components, reidentify the latch fitting assemblies, and check proximity sensors adjustment as necessary on the C-1A cargo door surround structure following Service Bulletin 093-52-083 or equivalent.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
within the next 300 hours' time in service after the effective date of this AD
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Lockheed-California Company Model L-1011-385 series airplanes with C-1A cargo door installed
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Federal Register Abstract
C-1A Cargo Doors
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_76-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes Subject: C-1A Cargo Doors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/20/1976 Make: Lockheed Martin Corporation Model: L-1011-385-1 | L-1011-385-1-14 | L-1011-385-1-15 | L-1011-385-3 Product Type: Aircraft Product Subtype: Large Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 76-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2745 AD NUMBER: 76-21-01 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes ACTION: SUMMARY: DATES: Effective November 20, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-21-01 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-2745. Applies to Lockheed Model L-1011-385 series airplanes certificated in all categories having C-1A cargo door installed. Compliance required within the next 300 hours' time in service after the effective date of this AD, unless already accomplished. To prevent the latch pins on the latch fittings of the C-1A cargo door surround structure from being incorrectly installed during maintenance replacement, which could result in a possible in-flight loss of the C-1A cargo door, accomplish the following: a. Install latch pin guard assemblies and related components, reidentify the latch fitting assemblies and check proximity sensors adjustment as necessary, on the C-1A cargo door surround structure, in accordance with Lockheed-California Company Service Bulletin 093-52-083 dated May 25, 1976, or later FAA-approved revision or equivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region. b. Airplanes may be flown in accordance with FAR 21.197 to a base where the modification can be performed. This amendment becomes effective November 20, 1976. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_76-21-01.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-21-01 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes Subject: C-1A Cargo Doors Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/20/1976 Make: Lockheed Martin Corporation Model: L-1011-385-1 | L-1011-385-1-14 | L-1011-385-1-15 | L-1011-385-3 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: 76-21-01 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2745 AD NUMBER: 76-21-01 SUBJECT HEADING: LOCKHEED-CALIFORNIA COMPANY Model L-1011-385 Series Airplanes ACTION: SUMMARY: DATES: Effective November 20, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-21-01 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-2745. Applies to Lockheed Model L-1011-385 series airplanes certificated in all categories having C-1A cargo door installed. Compliance required within the next 300 hours' time in service after the effective date of this AD, unless already accomplished. To prevent the latch pins on the latch fittings of the C-1A cargo door surround structure from being incorrectly installed during maintenance replacement, which could result in a possible in-flight loss of the C-1A cargo door, accomplish the following: a. Install latch pin guard assemblies and related components, reidentify the latch fitting assemblies and check proximity sensors adjustment as necessary, on the C-1A cargo door surround structure, in accordance with Lockheed-California Company Service Bulletin 093-52-083 dated May 25, 1976, or later FAA-approved revision or equivalent modification approved by the Chief, Aircraft Engineering Division, FAA Western Region. b. Airplanes may be flown in accordance with FAR 21.197 to a base where the modification can be performed. This amendment becomes effective November 20, 1976. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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