AD 93-21-08
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | DC-8-72 | Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes |
| aircraft | The Boeing Company | DC-8-72F | Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes |
| aircraft | The Boeing Company | DC-8-73 | Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes |
| aircraft | The Boeing Company | DC-8-73F | Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes |
Unsafe Condition
Reduced structural integrity of the pylon-to-wing main load path due to potential cracking in the front spar pylon support fittings (part numbers 5753054-501 and -502).
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Perform an eddy current inspection of the front spar pylon support fittings on number 2 and 3 engines per Alert Service Bulletin A57-99. Repeat inspections at intervals not exceeding 720 landings. If cracks are found, repair them prior to further flight per approved method.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Prior to the accumulation of 4,000 landings since installation of the engine, or within 6 months after December 13, 1993, whichever occurs later (unless previously accomplished within the last 720 landings before the effective date).
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
McDonnell Douglas DC-8-72, -72F, -73, and -73F series airplanes listed in Alert Service Bulletin A57-99 dated December 10, 1992.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
Front Spar Pylon Support Fittings
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_93-21-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-21-08 Document Type: AD Final Rules Docket Number: 93-NM-66-AD Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes Subject: Front Spar Pylon Support Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/13/1993 Make: The Boeing Company Model: DC-8-72 | DC-8-72F | DC-8-73 | DC-8-73F 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: 93-21-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-NM-66-AD AMENDMENT: 39-8722 AD NUMBER: 93-21-08 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes ACTION: SUMMARY: DATES: Effective December 13, 1993. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-21-08 MCDONNELL DOUGLAS: Amendment 39-8722. Docket 93-NM-66-AD. Applicability: Model DC-8-72, -72F, -73, and -73F series airplanes, as listed in McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent reduced structural integrity of the pylon-to-wing main load path, accomplish the following: (a) Perform an eddy current inspection of the front spar pylon support fittings (part numbers 5753054-501 and -502) on the number 2 and number 3 engines, in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992, and at the time specified in paragraph (a)(1) or (a)(2) of this AD, as applicable. Thereafter, repeat this inspection at intervals not to exceed 720 landings. (1) For the number 2 engine: Prior to the accumulation of 4,000 landings since installation of that engine, or within 6 months after the effective date of this AD, whichever occurs later, unless accomplished previously within the last 720 landings prior to the effective date of this AD. (2) For the number 3 engine: Prior to the accumulation of 4,000 landings since installation of that engine, or within 6 months after the effective date of this AD, whichever occurs later, unless accomplished previously within the last 720 landings prior to the effective date of this AD. (b) If any crack is found, prior to further flight, repair it in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. After repair, continue to repeat the inspection at intervals not to exceed 720 landings, in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles ACO, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The inspections shall be done in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 90846-1771, Attention: Business Unit Manager, Technical Publications - Technical Administrative Support, C1-L5B. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California 90806-2425; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (f) This amendment becomes effective on December 13, 1993. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_93-21-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 93-21-08 Document Type: AD Final Rules Docket Number: 93-NM-66-AD Subject Heading: Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes Subject: Front Spar Pylon Support Fittings Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 12/13/1993 Make: The Boeing Company Model: DC-8-72 | DC-8-72F | DC-8-73 | DC-8-73F 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: 93-21-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 93-NM-66-AD AMENDMENT: 39-8722 AD NUMBER: 93-21-08 SUBJECT HEADING: Airworthiness Directives; MCDONNELL DOUGLAS DC-8-72, -72F, -73, and -73F Series Airplanes ACTION: SUMMARY: DATES: Effective December 13, 1993. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 93-21-08 MCDONNELL DOUGLAS: Amendment 39-8722. Docket 93-NM-66-AD. Applicability: Model DC-8-72, -72F, -73, and -73F series airplanes, as listed in McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992, certificated in any category. Compliance: Required as indicated, unless accomplished previously. To prevent reduced structural integrity of the pylon-to-wing main load path, accomplish the following: (a) Perform an eddy current inspection of the front spar pylon support fittings (part numbers 5753054-501 and -502) on the number 2 and number 3 engines, in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992, and at the time specified in paragraph (a)(1) or (a)(2) of this AD, as applicable. Thereafter, repeat this inspection at intervals not to exceed 720 landings. (1) For the number 2 engine: Prior to the accumulation of 4,000 landings since installation of that engine, or within 6 months after the effective date of this AD, whichever occurs later, unless accomplished previously within the last 720 landings prior to the effective date of this AD. (2) For the number 3 engine: Prior to the accumulation of 4,000 landings since installation of that engine, or within 6 months after the effective date of this AD, whichever occurs later, unless accomplished previously within the last 720 landings prior to the effective date of this AD. (b) If any crack is found, prior to further flight, repair it in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. After repair, continue to repeat the inspection at intervals not to exceed 720 landings, in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992. (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles ACO, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO. NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO. (d) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (e) The inspections shall be done in accordance with McDonnell Douglas DC-8-70 Alert Service Bulletin A57-99, dated December 10, 1992. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from McDonnell Douglas Corporation, P.O. Box 1771, Long Beach, California 90846-1771, Attention: Business Unit Manager, Technical Publications - Technical Administrative Support, C1-L5B. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Transport Airplane Directorate, Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California 90806-2425; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (f) This amendment becomes effective on December 13, 1993. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
This site is not affiliated with or endorsed by the FAA. Always verify with official sources.
Related Airworthiness Directives
2023-12-15
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: 5G C-Band interference can cause radio altimeters to not perform their intended function, resulting in increased flightcrew workload while on approach with the flight director, autothrottle, or aut...
2023-10-02
final ruleAirworthiness Directives; Transport and Commuter Category Airplanes
Unsafe Condition: Radio altimeter anomalies that are undetected by the automation or pilot, particularly close to the ground (e.g., landing flare), could lead to loss of continued safe flight and landing. Additional...
2016-04-21 Recurring
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: Cracks in the lower skins, stringers, and fastener holes of the splice fittings, which could result in the loss of structural integrity of the airplane.
2014-22-10 Recurring
final ruleAirworthiness Directives; The Boeing Company Airplanes
Unsafe Condition: Cracking of the upper aft skin panel of the fuselage, subject to widespread fatigue damage (WFD), which could result in loss of structural integrity and consequent rapid decompression of the airplane.
