AD 91-15-21
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 727-100 Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-100C Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-200 Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727-200F Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727 Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
| aircraft | The Boeing Company | 727C Series | Airworthiness Directives; BOEING Model 727 Series Airplanes |
Unsafe Condition
Fuel leaking from auxiliary fuel tanks installed in the fuselage cargo compartments could lead to fire in the cargo compartment.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Within 1,000 flight cycles, conduct an ultrasonic inspection or leak check of auxiliary fuel tanks. Within 12,000 flight cycles, perform inspections of the tank and support structure, repeated every 12,000 flight cycles. Deactivation or removal is required if leakage is detected. Alternative methods may be approved by the FAA.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within the next 1,000 flight cycles after the effective date of this AD, and within the next 12,000 flight cycles after the effective date of this AD, with subsequent inspections at intervals not to exceed 12,000 flight cycles.
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Affected Aircraft
Boeing Model 727 series airplanes equipped with Boeing manufactured auxiliary fuel tanks in lower cargo compartments.
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Federal Register Abstract
Auxiliary Fuel Tanks
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_91-15-21.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-15-21 Document Type: AD Final Rules Docket Number: 91-NM-08-AD Subject Heading: Airworthiness Directives; BOEING Model 727 Series Airplanes Subject: Auxiliary Fuel Tanks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/09/1991 Make: The Boeing Company Model: 727-100 Series | 727-100C Series | 727-200 Series | 727-200F Series | 727 Series | 727C Series 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: 91-15-21 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-08-AD AMENDMENT: 39-7086 AD NUMBER: 91-15-21 SUBJECT HEADING: Airworthiness Directives; BOEING Model 727 Series Airplanes ACTION: SUMMARY: DATES: Effective September 9, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-15-21 BOEING: Amendment 39-7086. Docket No. 91-NM-08-AD. Applicability: Model 727 series airplanes, equipped with Boeing manufactured auxiliary fuel tanks installed in the lower cargo compartments, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To reduce the potential for fire in the cargo compartment due to fuel leaking from the auxiliary fuel tanks installed in the fuselage cargo compartments, accomplish the following: A. Within the next 1,000 flight cycles after the effective date of this AD, accomplish one of the following: 1. Conduct an ultrasonic inspection for disbonding of the lower sidewall (curved) panels of the auxiliary fuel tanks in accordance with Part I of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 2. Perform a leak check of the auxiliary fuel tanks in accordance with Part III of the Accomplishment Instruction in Boeing Service Bulletin 727-28-0110, dated September 6, 1990. If any fuel leakage is detected, prior to further flight repair, deactivate or remove the auxiliary fuel tanks, in accordance with Part III of the Accomplishment Instructions in the service bulletin. Repeat the leak check prior to each flight: B. Within the next 12,000 flight cycles after the effective date of this AD, accomplish the inspections of the auxiliary fuel tank and support structure in accordance with Part II of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990. Repeat this inspection at intervals not to exceed 12,000 flight cycles. Accomplishment of this inspection constitutes terminating action for the inspection/check requirements of paragraph A. of this AD. C. Deactivation of the auxiliary fuel tank in accordance with Part V of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990, constitutes terminating action for the inspection requirements of this AD. If the auxiliary fuel tanks are reactivated, the inspections required by paragraphs A. and B. of this AD must be accomplished prior to exceeding the flight cycle thresholds required by those paragraphs. NOTE: Fuel tanks deactivated, but installed in an airplane, accumulate the same number of flight cycles as the airplane. D. Auxiliary fuel tanks currently not installed in an airplane must be inspected in accordance with Part II of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990, prior to installation in an airplane. E. If a disbonded or cracked panel is detected during the inspections required by paragraphs A.1., B., C., or D. of this AD, accomplish one of the following prior to further flight. 1. Replace the panel in accordance with Part IV of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 2. Deactivate the auxiliary fuel tank in accordance with Part V of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 3. Remove the auxiliary fuel tank in accordance with the Boeing 727 Maintenance Manual Subject 53-20-31. F. 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO. G. 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 requirements of this AD. H. The inspection, deactivation, and replacement requirements shall be done in accordance with Boeing Service Bulletin 727-28-0110, dated September 6, 1990. 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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-7086, AD 91-15-21) becomes effective on September 9, 1991. FOOTER:
Document Text
Show stored source text (verify against official source)
AD Final Rules - DRS_91-15-21.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 91-15-21 Document Type: AD Final Rules Docket Number: 91-NM-08-AD Subject Heading: Airworthiness Directives; BOEING Model 727 Series Airplanes Subject: Auxiliary Fuel Tanks Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 09/09/1991 Make: The Boeing Company Model: 727-100 Series | 727-100C Series | 727-200 Series | 727-200F Series | 727 Series | 727C Series 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: 91-15-21 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: 91-NM-08-AD AMENDMENT: 39-7086 AD NUMBER: 91-15-21 SUBJECT HEADING: Airworthiness Directives; BOEING Model 727 Series Airplanes ACTION: SUMMARY: DATES: Effective September 9, 1991. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 91-15-21 BOEING: Amendment 39-7086. Docket No. 91-NM-08-AD. Applicability: Model 727 series airplanes, equipped with Boeing manufactured auxiliary fuel tanks installed in the lower cargo compartments, certificated in any category. Compliance: Required as indicated, unless previously accomplished. To reduce the potential for fire in the cargo compartment due to fuel leaking from the auxiliary fuel tanks installed in the fuselage cargo compartments, accomplish the following: A. Within the next 1,000 flight cycles after the effective date of this AD, accomplish one of the following: 1. Conduct an ultrasonic inspection for disbonding of the lower sidewall (curved) panels of the auxiliary fuel tanks in accordance with Part I of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 2. Perform a leak check of the auxiliary fuel tanks in accordance with Part III of the Accomplishment Instruction in Boeing Service Bulletin 727-28-0110, dated September 6, 1990. If any fuel leakage is detected, prior to further flight repair, deactivate or remove the auxiliary fuel tanks, in accordance with Part III of the Accomplishment Instructions in the service bulletin. Repeat the leak check prior to each flight: B. Within the next 12,000 flight cycles after the effective date of this AD, accomplish the inspections of the auxiliary fuel tank and support structure in accordance with Part II of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990. Repeat this inspection at intervals not to exceed 12,000 flight cycles. Accomplishment of this inspection constitutes terminating action for the inspection/check requirements of paragraph A. of this AD. C. Deactivation of the auxiliary fuel tank in accordance with Part V of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990, constitutes terminating action for the inspection requirements of this AD. If the auxiliary fuel tanks are reactivated, the inspections required by paragraphs A. and B. of this AD must be accomplished prior to exceeding the flight cycle thresholds required by those paragraphs. NOTE: Fuel tanks deactivated, but installed in an airplane, accumulate the same number of flight cycles as the airplane. D. Auxiliary fuel tanks currently not installed in an airplane must be inspected in accordance with Part II of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990, prior to installation in an airplane. E. If a disbonded or cracked panel is detected during the inspections required by paragraphs A.1., B., C., or D. of this AD, accomplish one of the following prior to further flight. 1. Replace the panel in accordance with Part IV of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 2. Deactivate the auxiliary fuel tank in accordance with Part V of the Accomplishment Instructions in Boeing Service Bulletin 727-28-0110, dated September 6, 1990; or 3. Remove the auxiliary fuel tank in accordance with the Boeing 727 Maintenance Manual Subject 53-20-31. F. 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, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO. G. 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 requirements of this AD. H. The inspection, deactivation, and replacement requirements shall be done in accordance with Boeing Service Bulletin 727-28-0110, dated September 6, 1990. 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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington; or at the Office of the Federal Register, 1100 L Street N.W., Room 8401, Washington, D.C. This amendment (39-7086, AD 91-15-21) becomes effective on September 9, 1991. FOOTER:
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Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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