# AD 92-16-18: Passenger Seat Reinforcement - Type: Airworthiness directive - Status: Current - Products: Cessna 401, 402, 402A, 402B, 402C, 404, 421, 421A, 421B, 421C, 441 and F406 - Effective: September 10, 1992 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-8328 - Docket: 91-CE-77-AD - Registered aircraft: 1,166 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/41F0CFC13CAFEC3786256A4E00716839.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/92-16-18 ## The airworthiness directive 92-16-18 CESSNA: Amendment 39-8328. Docket No. 91-CE-77-AD. Supersedes AD 78-06-03, Amendment 39-3162; and AD 88-19-02, Amendment 39-6004. Applicability: Models 401, 402, 402A, 402B, 402C, 404, F406, 421, 421A, 421B, 421C, and 441 airplanes (all serial numbers), certificated in any category, that: 1. Have Enviroform type commuter-style passenger seats installed at either manufacture or by field modification; and 2. Have not installed a structural reinforcement in accordance with the instructions in either Cessna Service Kit SK421-135A, revised August 5, 1988; or Cessna Service Kit SK421-78A, dated October 11, 1977, whichever is applicable. NOTE 1: Enviroform seats are molded fiberglass/Kevlar seats instead of the usual padded passenger seats. The seat cushion is held in place with velcro strips and may be removed to check for the installation of the reinforcement kit. The attach bolts and doubler for the reinforcement kit are prominently visible with the cushion removed. NOTE 2: None of the Model 401 airplanes were equipped with Enviroform type commuter-style passenger seats at manufacture, but could have had them installed at some point in service. Compliance: Upon the installation of any Enviroform commuter seat or within the next 100 hours time-in-service after the effective date of this AD, whichever occurs later, unless already accomplished. NOTE 3: The requirements of this AD may have already been accomplished in accordance with AD 78-06-03, Amendment 39-3162, or AD 88-19-02, Amendment 39-6004, which are both superseded by this AD. To prevent passenger injury caused by commuter seat failure, accomplish the following: (a) Remove, modify, and reinstall the Enviroform type commuter-style passenger seat in accordance with the applicable service information as specified in either paragraph (a)(1) or (a)(2) below: (1) In accordance with section A. of the MODIFICATION INSTRUCTIONS section of Cessna Service Kit SK421-135A, revised August 5, 1988, for the following model and serial number airplanes: Models Serial Numbers 402B and 402C 402B1047 through 402C1020 404 404-001 through 404-0859 421C 421C0055 through 421C1807 F406 F406-0001 through F406-0021 441 441-0001 through 441-0362 (2) In accordance with the MODIFICATION INSTRUCTIONS section of Cessna Service Kit SK421-78A, dated October 11, 1977, for the following model and serial number airplanes: Models Serial Numbers 401 and 402 401/402-0001 through 401/402-0322 402A 402A0001 through 402A0132 402B 402B0001 through 402B1046 421 421-001 through 421-0200 421A 421A0001 through 421A0158 421B 421B0001 through 421B0943 421C 421C0001 through 421C0054 (b) For Models 404, F406, and 441 airplanes, accomplish the seat tracking modification in accordance with section B. of the MODIFICATION INSTRUCTIONS section of Cessna Service Kit SK421-135A, revised August 5, 1988. (c) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished. (d) An alternative method of compliance or adjustment of the compliance time that provides an equivalent level of safety may be approved by the Manager, Wichita Aircraft Certification Office, 1801 Airport Road, Room 100, Mid-Continent Airport, Wichita, Kansas 67209. The request shall be forwarded through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Wichita Aircraft Certification Office. NOTE 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Wichita Aircraft Certification Office. (e) The modification required by this AD shall be done in accordance with Cessna Service Kit SK421-135A, revised August 5, 1988; or Cessna Service Kit SK421-78A, dated October 11, 1977. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR Part 51. Copies may be obtained from the Cessna Aircraft Company, P.O. Box 7704, Wichita, Kansas 67277. Copies may be inspected at the FAA, Central Region, Office of the Assistant Chief Counsel, Room 1558, 601 E. 12th Street, Kansas City, Missouri, or at the Office of the Federal Register, 800 North Capitol Street, NW, suite 700, Washington, DC. (f) This amendment (39-8328) supersedes AD 78-06-03, Amendment 39-3162, and AD 88-19-02, Amendment 39-6004. (g) This amendment becomes effective on September 10, 1992. ## Affected data sheets (4) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A7CE](https://openairdocs.org/tcds/A7CE): Textron Aviation Inc.; names 9 of 16 models: 421C, 402C, 402B, 402, 421B, 421A, 421, 402A… - [TCDS A25CE](https://openairdocs.org/tcds/A25CE): Textron Aviation Inc.; names 1 of 2 models: 404 - [TCDS A28CE](https://openairdocs.org/tcds/A28CE): Textron Aviation Inc.; names 1 of 1 models: 441 - [TCDS A54EU](https://openairdocs.org/tcds/A54EU): ASI Aviation; names 1 of 1 models: F406 ## Registered aircraft it may apply to (OpenAirDocs) Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment. - Aircraft: 1,166 (1,166 by airframe model, 0 by engine model) - Makers: Cessna 1,162, Reims 2, Reims Aviation S A 2 Models with the most aircraft: - [Cessna 421C](https://openairdocs.org/model/cessna-421c): 496 aircraft (airframe model) - [Cessna 421B](https://openairdocs.org/model/cessna-421b): 225 aircraft (airframe model) - [Cessna 441](https://openairdocs.org/model/cessna-441): 172 aircraft (airframe model) - [Cessna 402C](https://openairdocs.org/model/cessna-402c): 115 aircraft (airframe model) - [Cessna 402B](https://openairdocs.org/model/cessna-402b): 49 aircraft (airframe model) - [Cessna 421](https://openairdocs.org/model/cessna-421): 28 aircraft (airframe model) - [Cessna 404](https://openairdocs.org/model/cessna-404): 26 aircraft (airframe model) - [Cessna 401](https://openairdocs.org/model/cessna-401): 21 aircraft (airframe model) - [Cessna 421A](https://openairdocs.org/model/cessna-421a): 20 aircraft (airframe model) - [Cessna 402](https://openairdocs.org/model/cessna-402): 7 aircraft (airframe model) - [Cessna 402A](https://openairdocs.org/model/cessna-402a): 3 aircraft (airframe model) - [Reims Aviation S A F406](https://openairdocs.org/model/reims-aviation-s-a-f406): 2 aircraft (airframe model) - [Reims F406](https://openairdocs.org/model/reims-f406): 2 aircraft (airframe model) All 13 models: https://openairdocs.org/ad/92-16-18/models.md Every aircraft: https://openairdocs.org/ad/92-16-18/aircraft.md Its text cites no advisory circulars or STCs. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.