AD 77-09-02

final rule

Airworthiness Directives; CESSNA Models 421B and 421C Airplanes

AD Number
77-09-02
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Unknown
FR Citation
This information is not available.

Applicability

TypeManufacturerModelDetails
aircraft Cessna Aircraft Company 421B Airworthiness Directives; CESSNA Models 421B and 421C Airplanes
aircraft Cessna Aircraft Company 421C Airworthiness Directives; CESSNA Models 421B and 421C Airplanes

Unsafe Condition

Separation of the pilot's or co-pilot's windshields from the aircraft

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

Required Actions

Inspect and repair the pilot's and co-pilot's windshield installations per Cessna Service Letter ME77-5 and attachments, using specially trained personnel; or restrict operation to unpressurized cabin by securing the pressurization switch and installing a placard. Equivalent methods require FAA approval.

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

Compliance Time

Within 50 hours' time in service after the effective date for aircraft with 50+ hours' time in service or upon accumulation of 100 hours' time in service for those with 49 or fewer hours' time in service

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

Affected Aircraft

Cessna Models 421B (Serial Numbers 421B0301 thru 421B0970 except 421B0463, 421B0663, 421B0962) and 421C (Serial Numbers 421C0001 thru 421C0272 except 421C0224, 421C0232, 421C0246, 421C0260, 421C0261, 421C0264 thru 421C0271)

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

Federal Register Abstract

Windshield Inspection and Repair

Applicability Source Text

Show captured applicability text from the source AD
AD Final Rules - DRS_77-09-02.html
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AD Number:
77-09-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 421B and 421C Airplanes
Subject:
Windshield Inspection and Repair
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/09/1977
Make:
Cessna Aircraft Company
Model:
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Superseded AD: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Superseded By: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: 77-09-02
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-2883

AD NUMBER:   77-09-02

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 421B and 421C Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective May 9, 1977.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
77-09-02 CESSNA: Amendment 39-2883. Applies to Models 421B (Serial Numbers 421B0301 thru 421B0970 except 421B0463, 421B0663 and 421B0962) and 421C (Serial Numbers 421C0001 thru 421C0272 except 421C0224, 421C0232, 421C0246, 421C0260, 421C0261 and 421C0264 thru 421C0271) airplanes.

Compliance: Required as indicated, unless already accomplished.

To prevent separation of the pilot's or co-pilot's windshields from the aircraft, within 50 hours' time in service after the effective date of this AD for those aircraft having 50 hours' or more time in service or upon accumulation of 100 hours' time in service for those aircraft having 49 hours' or less time in service, accomplish either Paragraph A or B below:

A. Windshield Inspection and Repair:

(1) Visually inspect the pilot's and co-pilot's windshield installation and if necessary, repair in accordance with Cessna Service Letter ME77-5, dated March 14, 1977, or later approved revisions and Windshield Inspection and/or Modification Attachment thereto dated March 11, 1977, or later approved revisions.

(2) Paragraph A(1) must be accomplished only by maintenance personnel that have been specially trained by Cessna Aircraft Company or its designated representative for this purpose.

NOTE: Owners/operators should contact their local Cessna dealer to schedule their airplane into the nearest Cessna dealership having the specially trained personnel required to accomplish Paragraph A(1).

B. Unpressurized Aircraft Operation:

(1) Move the cabin pressurization switch to the "unpressurized" position and place adhesive tape over the switch to prevent its movement to the "pressurized" position.

(2) Fabricate a placard having white 3/16 inch or larger letters on a red background reading: "DO NOT PRESSURIZE CABIN".

(3) Install the placard fabricated in Paragraph B(2) just above or adjacent to the cabin pressurization switch and operate the aircraft in accordance with this limitation until Paragraph A is accomplished.

C. Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective May 9, 1977.

FOOTER:

Document Text

Show stored source text (verify against official source)
AD Final Rules - DRS_77-09-02.html
Copy URL
Print/Save as PDF
Document Versions
 Feedback
Details
AD Number:
77-09-02
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; CESSNA Models 421B and 421C Airplanes
Subject:
Windshield Inspection and Repair
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
05/09/1977
Make:
Cessna Aircraft Company
Model:
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: 77-09-02
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-2883

AD NUMBER:   77-09-02

SUBJECT HEADING:   Airworthiness Directives; CESSNA Models 421B and 421C Airplanes

ACTION:  

SUMMARY:  

DATES:   Effective May 9, 1977.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
77-09-02 CESSNA: Amendment 39-2883. Applies to Models 421B (Serial Numbers 421B0301 thru 421B0970 except 421B0463, 421B0663 and 421B0962) and 421C (Serial Numbers 421C0001 thru 421C0272 except 421C0224, 421C0232, 421C0246, 421C0260, 421C0261 and 421C0264 thru 421C0271) airplanes.

Compliance: Required as indicated, unless already accomplished.

To prevent separation of the pilot's or co-pilot's windshields from the aircraft, within 50 hours' time in service after the effective date of this AD for those aircraft having 50 hours' or more time in service or upon accumulation of 100 hours' time in service for those aircraft having 49 hours' or less time in service, accomplish either Paragraph A or B below:

A. Windshield Inspection and Repair:

(1) Visually inspect the pilot's and co-pilot's windshield installation and if necessary, repair in accordance with Cessna Service Letter ME77-5, dated March 14, 1977, or later approved revisions and Windshield Inspection and/or Modification Attachment thereto dated March 11, 1977, or later approved revisions.

(2) Paragraph A(1) must be accomplished only by maintenance personnel that have been specially trained by Cessna Aircraft Company or its designated representative for this purpose.

NOTE: Owners/operators should contact their local Cessna dealer to schedule their airplane into the nearest Cessna dealership having the specially trained personnel required to accomplish Paragraph A(1).

B. Unpressurized Aircraft Operation:

(1) Move the cabin pressurization switch to the "unpressurized" position and place adhesive tape over the switch to prevent its movement to the "pressurized" position.

(2) Fabricate a placard having white 3/16 inch or larger letters on a red background reading: "DO NOT PRESSURIZE CABIN".

(3) Install the placard fabricated in Paragraph B(2) just above or adjacent to the cabin pressurization switch and operate the aircraft in accordance with this limitation until Paragraph A is accomplished.

C. Any equivalent method of compliance with this AD must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region.

This amendment becomes effective May 9, 1977.

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.