AD 49-38-02
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | C54-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | C54A-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | C54B-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | C54D-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | C54E-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | C54G-DC | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
| aircraft | The Boeing Company | DC-4 | Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft |
Unsafe Condition
Fatigue failure of critical structural bolts in fuselage, wing, stabilizer, engine mount, and tail attachments due to insufficient fatigue life or improper material/heat treatment.
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Required Actions
Replace specified bolts in fuselage to center wing, outer wing to center wing, vertical stabilizer to fuselage tail, engine mount to firewall, and horizontal stabilizer to fuselage tail attachments with NAS bolts (rolled threads after heat treatment) or special studs as specified. Scrappage of removed bolts is required.
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Compliance Time
At every 9,000 hours total airplane flight time, with possible extension up to 18,000 hours if specific stud replacements are made. Extensions beyond 9,000 hours require CAA Inspector approval, not exceeding 1,500 hours after January 26, 1948, and must align with regular overhaul periods.
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Affected Aircraft
Douglas C-54 and DC-4 aircraft models including C54-DC, C54A-DC, C54B-DC, C54D-DC, C54E-DC, C54G-DC, and DC-4, all serial numbers.
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Federal Register Abstract
Bolt Replacement
Applicability Source Text
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AD Final Rules - DRS_49-38-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-38-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft Subject: Bolt Replacement Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: The Boeing Company Model: C54-DC | C54A-DC | C54B-DC | C54D-DC | C54E-DC | C54G-DC | DC-4 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: 49-38-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-38-02 SUBJECT HEADING: Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-38-02 DOUGLAS: Applies to All Models C-54 and DC-4 Aircraft. To be accomplished at every 9,000 hours total airplane flight time. In those cases where the present bolts have or will have accumulated more than 9,000 hours time prior to the next regular overhaul period, the first replacement time may be extended, at the discretion of the CAA Inspector, to coincide with a regular overhaul period but in no case should the adjustment time exceed 1,500 hours accumulated after January 26, 1948. Thereafter the bolt replacement shall be at the 9,000- or 18,000-hour period, whichever is applicable. Replace the following bolts: Fuselage to Center Wing Attachment; Outer Wing to Center Wing Attachment; Vertical Stabilizer Attachment to Fuselage Tail, Station 953; Engine Mount to Fire Wall Attachment; Horizontal Stabilizer to Fuselage Tail Assembly Attachment. The 9,000-hour period may be extended to 18,000 hours when studs 4105725-1 and -2 in outer wing attachment have been replaced with special studs Nos. 4357723-1 and -2 having letter "R" stamped on thread end and bolts in all other attachments listed are replaced with NAS bolts with threads rolled after heat treatment. The bolt part numbers and the number of bolts required are shown on pages 4 and 5 of the Douglas Service Magazine of August 1947. Bolts removed from the airplane are to be scrapped and are not to be used again. (Douglas Service Letter No. 66, Supplement No. 2, dated July 18, 1951, covers this same subject relative to wing alignment at Station 421.) This supersedes AD 48-04-03. FOOTER:
Document Text
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AD Final Rules - DRS_49-38-02.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 49-38-02 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft Subject: Bolt Replacement Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: Make: The Boeing Company Model: C54-DC | C54A-DC | C54B-DC | C54D-DC | C54E-DC | C54G-DC | DC-4 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: 49-38-02 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: AD NUMBER: 49-38-02 SUBJECT HEADING: Airworthiness Directives; DOUGLAS All Models C-54 and DC-4 Aircraft ACTION: SUMMARY: DATES: ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 49-38-02 DOUGLAS: Applies to All Models C-54 and DC-4 Aircraft. To be accomplished at every 9,000 hours total airplane flight time. In those cases where the present bolts have or will have accumulated more than 9,000 hours time prior to the next regular overhaul period, the first replacement time may be extended, at the discretion of the CAA Inspector, to coincide with a regular overhaul period but in no case should the adjustment time exceed 1,500 hours accumulated after January 26, 1948. Thereafter the bolt replacement shall be at the 9,000- or 18,000-hour period, whichever is applicable. Replace the following bolts: Fuselage to Center Wing Attachment; Outer Wing to Center Wing Attachment; Vertical Stabilizer Attachment to Fuselage Tail, Station 953; Engine Mount to Fire Wall Attachment; Horizontal Stabilizer to Fuselage Tail Assembly Attachment. The 9,000-hour period may be extended to 18,000 hours when studs 4105725-1 and -2 in outer wing attachment have been replaced with special studs Nos. 4357723-1 and -2 having letter "R" stamped on thread end and bolts in all other attachments listed are replaced with NAS bolts with threads rolled after heat treatment. The bolt part numbers and the number of bolts required are shown on pages 4 and 5 of the Douglas Service Magazine of August 1947. Bolts removed from the airplane are to be scrapped and are not to be used again. (Douglas Service Letter No. 66, Supplement No. 2, dated July 18, 1951, covers this same subject relative to wing alignment at Station 421.) This supersedes AD 48-04-03. FOOTER:
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