AD 91-24-08

final rule

Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes

AD Number
91-24-08
Status
final_rule
Effective Date
Product Category
aircraft
Docket
91-NM-221-AD
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft The Boeing Company MD-11 Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes
aircraft The Boeing Company MD-11F Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes

Unsafe Condition

Fatigue cracking and possible structural failure of the outboard flaps due to cracks in the outboard flap inboard and outboard closure rib spindle support fittings and delamination of the upper skin of the outboard flaps.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Perform a borescope inspection of spindle support fittings within 30 days after the AD's effective date or before 400 landings, whichever is later. Conduct a visual inspection of the upper skin for cracks and delamination within 30 days after the AD's effective date. If no issues found, either repeat inspections at specified intervals or modify the fittings as per the service bulletin. If cracks (less than 1 inch) are found, modify fittings or incorporate a permanent repair. For larger cracks or delamination, perform a permanent repair approved by the FAA.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

within 30 days after the effective date of this AD or prior to the accumulation of 400 landings, whichever occurs later

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

McDonnell Douglas MD-11 series airplanes, certificated in any category (models MD-11 and MD-11F)

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

Outboard Flaps

Applicability Source Text

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AD Number:
91-24-08
Document Type:
AD Final Rules
Docket Number:
91-NM-221-AD
Subject Heading:
Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes
Subject:
Outboard Flaps
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/12/1991
Make:
The Boeing Company
Model:
MD-11 | MD-11F
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Superseded AD: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: 91-24-08
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-NM-221-AD

AMENDMENT:   39-8094

AD NUMBER:   91-24-08

SUBJECT HEADING:   Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective December 12, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-24-08 McDONNELL DOUGLAS: Amendment 39-8094. Docket No. 91-NM-221-AD.

Applicability: Model MD-11 series airplanes, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent fatigue cracking and possible structural failure of the outboard flaps, accomplish the following:

(a) Prior to the accumulation of 400 landings, or within 30 days after the effective date of this AD, whichever occurs later, perform a borescope inspection to detect cracks in the left and right outboard flap inboard and outboard closure rib spindle support fittings, in accordance with Paragraph 2, "Accomplishment Instructions," of McDonnell Douglas Alert Service Bulletin A57-15, Revision 2, dated October 28, 1991 (hereinafter referred to as the Service Bulletin).

(b) Within 30 days after the effective date of this AD, perform a visual inspection for cracks and delamination of the upper skin of the outboard flaps in accordance with the Service Bulletin.

(c) If no cracking or delamination is found as a result of the inspections required by paragraphs (a) and (b) of this AD, accomplish either subparagraph (c)(1) or (c)(2) of this AD:

(1) Repeat the borescope inspections of the spindle support fittings required by paragraph (a) of this AD at intervals not to exceed 400 landings; and repeat the visual inspections of the upper skin required by paragraph (b) of this AD at intervals not to exceed 60 days. In cases where no cracking is found, the accomplishment of the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin constitutes terminating action for the repetitive inspections required by this paragraph. Or

(2) Prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin.

(d) If a crack with a length of less than 1 inch is found in the spindle support fitting as a result of the borescope inspections required by paragraphs (a) or (c)(1) of this AD, accomplish either subparagraph (d)(1) or (d)(2) of this AD:

(1) Prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin. In cases where such cracking is found, this modification is considered to be an interim (temporary) action only. Or

NOTE: The FAA is considering further rulemaking to require the accomplishment of a permanent repair.

(2) Prior to further flight, incorporate a permanent repair in a manner approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. The accomplishment of this permanent repair constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(e) If a crack with a length of greater than 1 inch is found in the spindle support fitting as a result of the borescope inspections required by paragraph (a) or (c)(1) of this AD, prior to further flight, accomplish a permanent repair in a manner approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Accomplishment of this permanent repair constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(f) If cracks or delamination are found in the skin as a result of the inspections required by paragraph (b) of this AD, prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin. Accomplishment of this modification constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(g) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may concur or comment and then send it to the Manager, Los Angeles ACO.

(h) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the inspection requirements of this AD.

(i) The inspection and modification requirements shall be done in accordance with McDonnell Douglas MD-11 Alert Service Bulletin A57-15, revision 2, dated October 28, 1991. 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, Technical Publications-Technical Administrative Support, C1-L5B, 3855 Lakewood Boulevard, Long Beach, California 90846. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C.

This amendment (39-8094, AD 91-24-08) becomes effective on December 12, 1991.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_91-24-08.html
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 Feedback
Details
AD Number:
91-24-08
Document Type:
AD Final Rules
Docket Number:
91-NM-221-AD
Subject Heading:
Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes
Subject:
Outboard Flaps
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
12/12/1991
Make:
The Boeing Company
Model:
MD-11 | MD-11F
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: 91-24-08
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   91-NM-221-AD

AMENDMENT:   39-8094

AD NUMBER:   91-24-08

SUBJECT HEADING:   Airworthiness Directives: McDONNELL DOUGLAS MD-11 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective December 12, 1991.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:   91-24-08 McDONNELL DOUGLAS: Amendment 39-8094. Docket No. 91-NM-221-AD.

Applicability: Model MD-11 series airplanes, certificated in any category.

Compliance: Required as indicated, unless previously accomplished.

To prevent fatigue cracking and possible structural failure of the outboard flaps, accomplish the following:

(a) Prior to the accumulation of 400 landings, or within 30 days after the effective date of this AD, whichever occurs later, perform a borescope inspection to detect cracks in the left and right outboard flap inboard and outboard closure rib spindle support fittings, in accordance with Paragraph 2, "Accomplishment Instructions," of McDonnell Douglas Alert Service Bulletin A57-15, Revision 2, dated October 28, 1991 (hereinafter referred to as the Service Bulletin).

(b) Within 30 days after the effective date of this AD, perform a visual inspection for cracks and delamination of the upper skin of the outboard flaps in accordance with the Service Bulletin.

(c) If no cracking or delamination is found as a result of the inspections required by paragraphs (a) and (b) of this AD, accomplish either subparagraph (c)(1) or (c)(2) of this AD:

(1) Repeat the borescope inspections of the spindle support fittings required by paragraph (a) of this AD at intervals not to exceed 400 landings; and repeat the visual inspections of the upper skin required by paragraph (b) of this AD at intervals not to exceed 60 days. In cases where no cracking is found, the accomplishment of the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin constitutes terminating action for the repetitive inspections required by this paragraph. Or

(2) Prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin.

(d) If a crack with a length of less than 1 inch is found in the spindle support fitting as a result of the borescope inspections required by paragraphs (a) or (c)(1) of this AD, accomplish either subparagraph (d)(1) or (d)(2) of this AD:

(1) Prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin. In cases where such cracking is found, this modification is considered to be an interim (temporary) action only. Or

NOTE: The FAA is considering further rulemaking to require the accomplishment of a permanent repair.

(2) Prior to further flight, incorporate a permanent repair in a manner approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. The accomplishment of this permanent repair constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(e) If a crack with a length of greater than 1 inch is found in the spindle support fitting as a result of the borescope inspections required by paragraph (a) or (c)(1) of this AD, prior to further flight, accomplish a permanent repair in a manner approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Accomplishment of this permanent repair constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(f) If cracks or delamination are found in the skin as a result of the inspections required by paragraph (b) of this AD, prior to further flight, accomplish the modification shown in Figures 3 and 4 and described in Tables I and II of the Service Bulletin. Accomplishment of this modification constitutes terminating action for the repetitive inspections required by paragraph (c)(1) of this AD.

(g) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.

NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may concur or comment and then send it to the Manager, Los Angeles ACO.

(h) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the inspection requirements of this AD.

(i) The inspection and modification requirements shall be done in accordance with McDonnell Douglas MD-11 Alert Service Bulletin A57-15, revision 2, dated October 28, 1991. 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, Technical Publications-Technical Administrative Support, C1-L5B, 3855 Lakewood Boulevard, Long Beach, California 90846. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Los Angeles Aircraft Certification Office, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C.

This amendment (39-8094, AD 91-24-08) becomes effective on December 12, 1991.

FOOTER:

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Retrieved: Apr 8, 2026

Rights: U.S. Government Public Domain

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