AD 79-20-11

final rule

BOEING Model 747 Series Airplanes

AD Number
79-20-11
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of an aircraft fuel pump, filter, valve, and lines
Problem area Fuel system

Applicability

TypeManufacturerModelDetails
aircraft The Boeing Company 747-100 Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-100B Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-100B SUD Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-200B Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-200C Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-200F Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-300 Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-400 Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-400D Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747-400F Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747SP Series BOEING Model 747 Series Airplanes
aircraft The Boeing Company 747SR Series BOEING Model 747 Series Airplanes

Unsafe Condition

Failure of the lightning protection design of the fuel system could result in fuel tank ignition sources due to lightning strikes.

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

Required Actions

Accomplish modifications to the outboard wing fuel system components, install wiring shrouds and a relay circuit for the fuel quantity system, and replace nonmetallic fuel tank and dry bay access doors as per specified service bulletins or equivalent FAA-approved methods.

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

Compliance Time

Within 5000 hours time in service or fifteen calendar months from the effective date, whichever occurs first

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

Affected Aircraft

Boeing Model 747 series airplanes certificated in all categories, including 747-100, 747-100B, 747-100B SUD, 747-200B, 747-200C, and other 747-200 series models.

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

Federal Register Abstract

Lightening Protection Of Fuel System

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_79-20-11.html
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AD Number:
79-20-11
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
BOEING Model 747 Series Airplanes
Subject:
Lightening Protection Of Fuel System
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
10/15/1979
Make:
The Boeing Company
Model:
747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...Show more
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: 79-20-11
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-3583

AD NUMBER:   79-20-11

SUBJECT HEADING:   BOEING Model 747 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective October 15, 1979.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
79-20-11 BOEING: Amendment 39-3583. Applies to Boeing Model 747 series airplanes certificated in all categories. Compliance required as indicated. To improve the lightning protection design of the fuel system, accomplish the following: Within 5000 hours time in service or fifteen calendar months from the effective date, whichever occurs first, modify the fuel systems as follows, unless already accomplished or an equivalent modification was incorporated during production:

A. Rework the outboard wing fuel system components in accordance with Boeing Service Bulletin 747-28-2068, Revision 3, dated September 28, 1979, or later FAA-approved revisions.
B. Install wiring shrouds and a relay circuit for the fuel quantity system in accordance with Boeing Service Bulletin 747-28-2069 dated June 1, 1979, Revision 1 dated October 5, 1979, or later FAA-approved revisions.
C. Replace the nonmetallic fuel tank and dry bay access doors in accordance with Boeing Service Bulletin 747-57-2035 dated December 18, 1970, and 747-28-2084 Revision 1, dated June 8, 1979, or later FAA-approved revisions.
Equivalent modifications may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108.
The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1).
All persons affected by this directive who have not already received these documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplane Company, Post Office Box 3707, Seattle, Washington 91824. These documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108.

This amendment becomes effective October 15, 1979.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_79-20-11.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
79-20-11
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
BOEING Model 747 Series Airplanes
Subject:
Lightening Protection Of Fuel System
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
10/15/1979
Make:
The Boeing Company
Model:
747-100 Series | 747-100B Series | 747-100B SUD Series | 747-200B Series | 747-200C Series | 747-200...Show more
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: 79-20-11
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-3583

AD NUMBER:   79-20-11

SUBJECT HEADING:   BOEING Model 747 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective October 15, 1979.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
79-20-11 BOEING: Amendment 39-3583. Applies to Boeing Model 747 series airplanes certificated in all categories. Compliance required as indicated. To improve the lightning protection design of the fuel system, accomplish the following: Within 5000 hours time in service or fifteen calendar months from the effective date, whichever occurs first, modify the fuel systems as follows, unless already accomplished or an equivalent modification was incorporated during production:

A. Rework the outboard wing fuel system components in accordance with Boeing Service Bulletin 747-28-2068, Revision 3, dated September 28, 1979, or later FAA-approved revisions.
B. Install wiring shrouds and a relay circuit for the fuel quantity system in accordance with Boeing Service Bulletin 747-28-2069 dated June 1, 1979, Revision 1 dated October 5, 1979, or later FAA-approved revisions.
C. Replace the nonmetallic fuel tank and dry bay access doors in accordance with Boeing Service Bulletin 747-57-2035 dated December 18, 1970, and 747-28-2084 Revision 1, dated June 8, 1979, or later FAA-approved revisions.
Equivalent modifications may be used when approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108.
The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1).
All persons affected by this directive who have not already received these documents from the manufacturer, may obtain copies upon request to Boeing Commercial Airplane Company, Post Office Box 3707, Seattle, Washington 91824. These documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108.

This amendment becomes effective October 15, 1979.

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.