AD 72-02-01

final rule

Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes

AD Number
72-02-01
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.
Technical illustration of an aircraft propeller assembly
Problem area Propeller

Applicability

TypeManufacturerModelDetails
aircraft Cessna Aircraft Company 411 Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
aircraft Cessna Aircraft Company 411A Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
aircraft Cessna Aircraft Company 421 Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
aircraft Cessna Aircraft Company 421A Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
aircraft Cessna Aircraft Company 421B Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes

Unsafe Condition

Propeller separation in flight as a result of rough engine operation.

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

Required Actions

Check torque on propeller attachment nuts using specified torque values and adapters. Perform detailed inspection if nuts are loose. Modify engine tachometer with yellow arcs, install operational placards, replace Airplane Flight Manual pages with specified revisions, and obtain approval for equivalent methods if needed.

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

Compliance Time

within the next 50 hours' time in service after the effective date of this AD

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

Affected Aircraft

Cessna Models 411, 411A, 421, 421A, and 421B (up to and including Serial Number 421B0147)

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

Federal Register Abstract

Propeller Attachment Nuts

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_72-02-01.html
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Details
AD Number:
72-02-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
Subject:
Propeller Attachment Nuts
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/18/1972
Make:
Cessna Aircraft Company
Model:
411 | 411A | 421 | 421A | 421B
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: 72-02-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1379

AD NUMBER:   72-02-01

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective January 18, 1972.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
72-02-01 CESSNA: Amendment 39-1379. Applies to Models 411, 411A, 421, 421A and 421B (up to and including Serial Number 421B0147) airplanes.

Compliance: Required within the next 50 hours' time in service after the effective date of this AD, unless already accomplished:

To prevent possible propeller separation in flight as a result of rough engine operation, accomplish the following:

A) Check the torque on the propeller attachment nuts by applying 80 to 85 ft. lbs. torque. Nuts which do not move when the proper torque is applied should not be further tightened. If any nuts are found loose (70 Ft. lbs. torque or less), complete the detailed inspection required by Cessna Service Letter ME71-16 Supplement No. 2, dated January 7, 1972. (See Note)

NOTE: A special adapter, Cessna P/N 5090006-5 for Hartzell propellers or P/N 5090006-9 for McCauley propellers, or equivalent, is required to accomplish the above torque check.

B) Modify the engine tachometer by incorporating a yellow arc restricting continuous engine operation for Models 411 and 411A airplanes between 2100 and 2350 rpm, and for Models 421, 421A and 421B airplanes between 1950 and 2225 rpm.

C) Install appropriate operational placard on the engine tachometer with the following wording: "AVOID CONTINUOUS OPERATION IN YELLOW ARC"

D) Replace existing Airplane Flight Manual pages with the following FAA/DOA approved revised Airplane Flight Manual pages, or later FAA/DOA approved revision, as appropriate:

1. Model 411 - Revision No. 12 dated December 7, 1971.

2. Model 411A - Revision No. 4 dated December 7, 1971.

3. Model 421 - Revision No. 8 dated December 8, 1971.

4. Model 421A - Revision No. 4 dated December 8, 1971.

5. Model 421B (Serial Numbers 421B001 through 421B0147) - Revision No. 4 dated December 1, 1971.

E) Equivalent methods of compliance with this AD must be approved by Chief, Engineering and Manufacturing Branch, FAA, Central Region.

Cessna Service Letter ME71-16 Supplement No. 2 dated January 7, 1972, pertains to this subject.

NOTE: This does not preclude continued recheck of propeller attach bolt as required by FAR 91 and specified for each 100 hours' time in service per Cessna Service Instructions.

This amendment becomes effective January 18, 1972.


FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_72-02-01.html
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Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
72-02-01
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes
Subject:
Propeller Attachment Nuts
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
01/18/1972
Make:
Cessna Aircraft Company
Model:
411 | 411A | 421 | 421A | 421B
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: 72-02-01
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-1379

AD NUMBER:   72-02-01

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 411, 411A, 421, 421A and 421B Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective January 18, 1972.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
72-02-01 CESSNA: Amendment 39-1379. Applies to Models 411, 411A, 421, 421A and 421B (up to and including Serial Number 421B0147) airplanes.

Compliance: Required within the next 50 hours' time in service after the effective date of this AD, unless already accomplished:

To prevent possible propeller separation in flight as a result of rough engine operation, accomplish the following:

A) Check the torque on the propeller attachment nuts by applying 80 to 85 ft. lbs. torque. Nuts which do not move when the proper torque is applied should not be further tightened. If any nuts are found loose (70 Ft. lbs. torque or less), complete the detailed inspection required by Cessna Service Letter ME71-16 Supplement No. 2, dated January 7, 1972. (See Note)

NOTE: A special adapter, Cessna P/N 5090006-5 for Hartzell propellers or P/N 5090006-9 for McCauley propellers, or equivalent, is required to accomplish the above torque check.

B) Modify the engine tachometer by incorporating a yellow arc restricting continuous engine operation for Models 411 and 411A airplanes between 2100 and 2350 rpm, and for Models 421, 421A and 421B airplanes between 1950 and 2225 rpm.

C) Install appropriate operational placard on the engine tachometer with the following wording: "AVOID CONTINUOUS OPERATION IN YELLOW ARC"

D) Replace existing Airplane Flight Manual pages with the following FAA/DOA approved revised Airplane Flight Manual pages, or later FAA/DOA approved revision, as appropriate:

1. Model 411 - Revision No. 12 dated December 7, 1971.

2. Model 411A - Revision No. 4 dated December 7, 1971.

3. Model 421 - Revision No. 8 dated December 8, 1971.

4. Model 421A - Revision No. 4 dated December 8, 1971.

5. Model 421B (Serial Numbers 421B001 through 421B0147) - Revision No. 4 dated December 1, 1971.

E) Equivalent methods of compliance with this AD must be approved by Chief, Engineering and Manufacturing Branch, FAA, Central Region.

Cessna Service Letter ME71-16 Supplement No. 2 dated January 7, 1972, pertains to this subject.

NOTE: This does not preclude continued recheck of propeller attach bolt as required by FAR 91 and specified for each 100 hours' time in service per Cessna Service Instructions.

This amendment becomes effective January 18, 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.