# AD 75-09-05: Pitot System - Type: Airworthiness directive - Status: Current - Products: Cessna 337, 337A, 337B, 337C, 337D, 337E, 337F, 337G and 337H with STC SA1627WE - Effective: April 22, 1975 - Superseded by: Nothing supersedes this AD - Product type: Aircraft, Small airplane - Amendment: 39-2177 - Registered aircraft: 371 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/8BDF6D87946A732386256A340065063C.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/75-09-05 ## The airworthiness directive 75-09-05 CESSNA: Amendment 39-2177. Applies to the following Model 337 series aircraft modified in accordance with Robertson Aircraft Corporation STC SA1627WE, certificated in all categories. 337-0058, 337-0063, 337-0124, 337-0205, 337-0220, 337-0291, 337-0305, 337-0327, 337-0332, 337-0443, 337-0502, 337-0540, 337-0549, 337-0566, 337-0577, 337-0685, 337-0695, 337-0726, 337-0728, 337-0732, 337-0741, 337-0817, 337-0822, 337-0836, 337-0880, 337-0882, 337-0896, 337-0916, 337-0925, 337-0929, 337-0938, 337-0942, 337-0946, 337-0947, 337-0959, 337-0963, 337-0970, 337-0977, 337-0992, 337-0996, 337-1019, 337-1036, 337-1044, 337-1052, 337-1062, 337-1072, 337-1073, 337-1079, 337-1082, 337-1091, 337-1108, 337-1118, 337-1124, 337-1139, 337-1154, 337-1159, 337-1162, 337-1175, 337-1177, 337-1180, 337-1192, 337-1210, 337-1232, 337-1258, 337-1262, 337-1274, 337-1276, 337-1303, 337-1307 Compliance required as indicated unless already accomplished. To prevent the possibility of unreliable airspeed indications due to ice formation in the pitot system, accomplish the following: Unless already accomplished, within the next 100 hours of operation after the effective date of this AD, rework the extended pitot tube by installation of Robertson Kit No. 14-118-100 in accordance with Robertson modification instructions No. 14-118-10 dated January 23, 1975, or later FAA approved revisions, or in a manner approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region. The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Robertson Aircraft Corporation, 839 West Perimeter Road, Renton, Washington 98055. The documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington. This amendment becomes effective April 22, 1975. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS A6CE](https://openairdocs.org/tcds/A6CE): Textron Aviation Inc.; names 9 of 19 models: 337, 337D, 337G, 337H, 337F, 337C, 337A, 337E… ## 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: 371 (371 by airframe model, 0 by engine model) - Makers: Cessna 370, Cessna Conroy 1 Models with the most aircraft: - [Cessna 337G](https://openairdocs.org/model/cessna-337g): 96 aircraft (airframe model) - [Cessna 337A](https://openairdocs.org/model/cessna-337a): 55 aircraft (airframe model) - [Cessna 337](https://openairdocs.org/model/cessna-337): 50 aircraft (airframe model) - [Cessna 337D](https://openairdocs.org/model/cessna-337d): 42 aircraft (airframe model) - [Cessna 337B](https://openairdocs.org/model/cessna-337b): 40 aircraft (airframe model) - [Cessna 337C](https://openairdocs.org/model/cessna-337c): 33 aircraft (airframe model) - [Cessna 337F](https://openairdocs.org/model/cessna-337f): 24 aircraft (airframe model) - [Cessna 337E](https://openairdocs.org/model/cessna-337e): 21 aircraft (airframe model) - [Cessna 337H](https://openairdocs.org/model/cessna-337h): 9 aircraft (airframe model) - [Cessna Conroy 337A](https://openairdocs.org/model/cessna-conroy-337a): 1 aircraft (airframe model) All 10 models: https://openairdocs.org/ad/75-09-05/models.md Every aircraft: https://openairdocs.org/ad/75-09-05/aircraft.md ## Related documents - [STC SA1627WE](https://openairdocs.org/stc/SA1627WE): Installation of drooped ailerons in flaps down mode, recontoured wing leading edge, stall fences, aileron centering springs, conical cambered wing tips and flap actuated elevator trim spring.. Sierra Industries Ltd., Named in the applicability --- 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.