AD 72-11-05

final rule

Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes

AD Number
72-11-05
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Cessna Aircraft Company 411 Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
aircraft Cessna Aircraft Company 411A Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
aircraft Cessna Aircraft Company 421 Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
aircraft Cessna Aircraft Company 421A Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
aircraft Cessna Aircraft Company 421B Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
aircraft Cessna Aircraft Company 421C Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes

Unsafe Condition

Auxiliary fuel cell leakage could result in possible fire and explosion hazards from fuel vapor ignition.

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

Required Actions

Visually inspect the lower wing surfaces near auxiliary fuel cells for stains/leakage. Replace leaking cells with improved cells per Cessna Service Letter ME72-8. For Model 411 (411-0001-0200), daily inspections until January 1, 1973, then mandatory replacement. For Model 411 (411-0201-0300) and Model 421 (421-0001-421B0048), inspections every 100 flight hours until improved cells are installed.

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

Compliance Time

Within 10 hours' time in service after the effective date of this AD, and thereafter as specified (daily or every 100 flight hours).

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

Affected Aircraft

Cessna Model 411 (Serial Numbers 411-0001 thru 411-0300) and Model 421 (Serial Numbers 421-0001 thru 421B0048) airplanes.

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

Federal Register Abstract

Auxiliary Fuel Cell Leaks

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_72-11-05.html
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AD Number:
72-11-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
Subject:
Auxiliary Fuel Cell Leaks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
06/02/1972
Make:
Cessna Aircraft Company
Model:
411 | 411A | 421 | 421A | 421B | 421C
Product Type:
Aircraft
Product Subtype:
Small 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: 72-11-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1454

AD NUMBER:   72-11-05

SUBJECT HEADING:   Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective June 2, 1972.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
72-11-05 CESSNA: Amdt. 39-1454. Applies to Models 411 and 421 series airplanes.

Compliance: Required as indicated, unless already accomplished.

In order to detect auxiliary fuel cell leakage that could result in possible fire and explosion hazards from fuel vapor ignition, accomplish the following:

A) On Model 411 (Serial Numbers 411-0001 thru 411-0200) airplanes:

1) Within 10 hours' time in service after the effective date of this AD, and thereafter prior to the first flight of each day, visually inspect the lower surface of the wings in the area of the auxiliary fuel cells for fuel stains and leakage. If auxiliary fuel cell leakage is observed, prior to further flight, replace the auxiliary fuel cells with improved auxiliary fuel cells in accordance with Cessna Service Letter ME72-8, dated April 21, 1972, or any equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

2) The repetitive inspections required prior to the first flight of each day may be performed by the pilot, including pilots of aircraft engaged in air taxi operations. A chronological listing of compliance with this AD must be made in the airplane's permanent maintenance log in accordance with FAR 91.173.

3) On or before January 1, 1973, replace all auxiliary fuel cells with the improved auxiliary fuel cells specified in Cessna Service Letter ME72-8, dated April 21, 1972.

4) The repetitive inspections required in Paragraph A(1) may be discontinued when the improved auxiliary fuel cells are installed.

B) On Model 411 (Serial Numbers 411-0201 thru 411-0300) airplanes and on Model 421 (Serial Numbers 421-0001 thru 421B0048) airplanes, within 10 hours' time in service after the effective date of this AD and thereafter at intervals not to exceed 100 hours' time in service from the date of the last inspection, visually inspect the lower surface of the wings in the area of the auxiliary fuel cells for stains or leakage. If auxiliary fuel cell leakage is observed, prior to further flight, replace the auxiliary fuel cells with improved auxiliary fuel cells in accordance with Cessna Service Letter ME72-8, dated April 21, 1972, or any equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. The repetitive inspections required in this paragraph may be discontinued when the improved auxiliary fuel cells are installed.

This amendment becomes effective June 2, 1972.


FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_72-11-05.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
72-11-05
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes
Subject:
Auxiliary Fuel Cell Leaks
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
06/02/1972
Make:
Cessna Aircraft Company
Model:
411 | 411A | 421 | 421A | 421B | 421C
Product Type:
Aircraft
Product Subtype:
Small 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: 72-11-05
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1454

AD NUMBER:   72-11-05

SUBJECT HEADING:   Airworthiness Directives; CESSNA Model 411 and 421 Series Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective June 2, 1972.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
72-11-05 CESSNA: Amdt. 39-1454. Applies to Models 411 and 421 series airplanes.

Compliance: Required as indicated, unless already accomplished.

In order to detect auxiliary fuel cell leakage that could result in possible fire and explosion hazards from fuel vapor ignition, accomplish the following:

A) On Model 411 (Serial Numbers 411-0001 thru 411-0200) airplanes:

1) Within 10 hours' time in service after the effective date of this AD, and thereafter prior to the first flight of each day, visually inspect the lower surface of the wings in the area of the auxiliary fuel cells for fuel stains and leakage. If auxiliary fuel cell leakage is observed, prior to further flight, replace the auxiliary fuel cells with improved auxiliary fuel cells in accordance with Cessna Service Letter ME72-8, dated April 21, 1972, or any equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

2) The repetitive inspections required prior to the first flight of each day may be performed by the pilot, including pilots of aircraft engaged in air taxi operations. A chronological listing of compliance with this AD must be made in the airplane's permanent maintenance log in accordance with FAR 91.173.

3) On or before January 1, 1973, replace all auxiliary fuel cells with the improved auxiliary fuel cells specified in Cessna Service Letter ME72-8, dated April 21, 1972.

4) The repetitive inspections required in Paragraph A(1) may be discontinued when the improved auxiliary fuel cells are installed.

B) On Model 411 (Serial Numbers 411-0201 thru 411-0300) airplanes and on Model 421 (Serial Numbers 421-0001 thru 421B0048) airplanes, within 10 hours' time in service after the effective date of this AD and thereafter at intervals not to exceed 100 hours' time in service from the date of the last inspection, visually inspect the lower surface of the wings in the area of the auxiliary fuel cells for stains or leakage. If auxiliary fuel cell leakage is observed, prior to further flight, replace the auxiliary fuel cells with improved auxiliary fuel cells in accordance with Cessna Service Letter ME72-8, dated April 21, 1972, or any equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. The repetitive inspections required in this paragraph may be discontinued when the improved auxiliary fuel cells are installed.

This amendment becomes effective June 2, 1972.


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.