# AD 76-04-01: Main Gear Extension - Type: Airworthiness directive - Status: Current - Products: Cessna 210, 210A, 210B, 210C and 210D - Effective: January 27, 1977 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-2810 - Registered aircraft: 554 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/D313A249139D7B1A86256E0D00503C84.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/76-04-01 ## The airworthiness directive 76-04-01 CESSNA: Amendment 39-2517 as amended by Amendment 39-2556, 39-2686 and 39-2767 is further amended by Amendment 39-2810. Applies to Models 210 through 210D (Serial Numbers 57001 thru 57575 and 21057576 thru 21058510) airplanes on which are installed Electrol manufactured main gear rotary actuator assemblies, Cessna P/Ns 1280102-1 and -2 (Electrol P/Ns EA 1471-1 and -2) or Cessna P/Ns 1280501-1 and -2 (Electrol P/Ns EA 1614-1 and -2). This AD does not apply to those airplanes on which Cessna P/Ns 1280511-3/4 and 1298100-1/2 actuator assemblies are installed. Compliance: Required as indicated, unless already accomplished in accordance with this AD, previous maintenance or AD 71-24-07. To decrease the possibility of main gear extension failure, accomplish the following: On or before April 1, 1977, or within 100 hours' time in service after February 26, 1976, whichever occurs later, install Cessna Kits 1209005-1 R/L in accordance with Cessna Service Letter SE75-21 dated October 3, 1975, or later approved revisions, or an equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, Central Region. NOTE 1) The landing gear actuator assemblies having Cessna P/Ns and manufactured by Electrol can be identified by using an inspection mirror through the inspection plate located forward of the strut doors to read the actuator nameplate. NOTE 2) A significant savings of manhours will result if compliance with this AD and the modifications and/or inspections required by AD 76-14-07 (Amendment 39-2670 - landing gear saddle fittings) are accomplished at the same time. NOTE 3) It is imperative that Cessna P/N 1209005-1 R/L Kits be ordered from the manufacturer immediately to assure that a sufficient supply of kits will be available to allow modification of all affected aircraft on or before April 1, 1977. Amendment 39-2517 superseded AD 71-24-07, Amendment 39-1345. Amendment 39-2517 became effective February 26, 1976. Amendment 39-2556 became effective March 26, 1976. Amendment 39-2686 became effective August 12, 1976, and replaces Amendments 39-2517 and 39-2556. Amendment 39-2767 became effective November 2, 1976, and supplements Amendment 39-2686. Amendment 39-2686 in turn replaced Amendments 39-2517 and 39-2556. This amendment, 39-2810, becomes effective January 27, 1977, and supplements Amendments 39-2686 and 39-2767. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 3A21](https://openairdocs.org/tcds/3A21): Textron Aviation Inc.; names 5 of 28 models: 210D, 210, 210B, 210A, 210C ## 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: 554 (554 by airframe model, 0 by engine model) - Makers: Cessna 554 Models with the most aircraft: - [Cessna 210](https://openairdocs.org/model/cessna-210): 188 aircraft (airframe model) - [Cessna 210D](https://openairdocs.org/model/cessna-210d): 123 aircraft (airframe model) - [Cessna 210B](https://openairdocs.org/model/cessna-210b): 101 aircraft (airframe model) - [Cessna 210A](https://openairdocs.org/model/cessna-210a): 85 aircraft (airframe model) - [Cessna 210C](https://openairdocs.org/model/cessna-210c): 57 aircraft (airframe model) All 5 models: https://openairdocs.org/ad/76-04-01/models.md Every aircraft: https://openairdocs.org/ad/76-04-01/aircraft.md Its text cites no advisory circulars or STCs. ## NTSB investigations that cite this AD (2) From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. - [NTSB WPR23LA213](https://openairdocs.org/ntsb/WPR23LA213), May 30, 2023: Cessna 210 (N9574X), Tacoma, WA, substantial damage. Probable cause: A fatigue failure of the left main landing gear hydraulic actuator, which resulted in a loss of hydraulic fluid that prevented the pilot from lowering the landing gear to the fully extended position… - [NTSB ANC18LA019](https://openairdocs.org/ntsb/ANC18LA019), Jan 14, 2018: Cessna 210 (N3607Y), Juneau, AK, substantial damage. Probable cause: A loss of hydraulic fluid due to a fatigue failure of the right main landing gear hydraulic actuator, which resulted in the pilot's inability to fully extend the landing gear and a main landing gear… --- 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.