AD 77-09-02

Airworthiness directive · Windshield Inspection and Repair · Cessna 421B and 421C

Effective
May 9, 1977
Models
421B, 421C
Data sheet
TCDSA7CE
Registered aircraft
721 matched by model
Product
Aircraft · Small airplane
Amendment
39-2883

Unofficial copy of the text in the FAA’s Dynamic Regulatory System. The FAA’s own copy is the authoritative one. DRS record last changed May 30, 2024.

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The airworthiness directive

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.

Affected TCDS · 1

The type certificate data sheets for the models this AD names, matched by model and maker.

Registered aircraft · 721

Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.

By aircraft maker
  • Cessna721 aircraft
By year built
19701993
Registered aircraft by year built: 470 aircraft
19706
19716
197219
197350
197457
197554
197653
197751
197837
197936
198033
198136
198218
19832
19848
19853
19931

251 with no year recorded

By model

Aircraft

See all 721 aircraft