# AD 80-23-02: Turbine Power Conversions - Type: Airworthiness directive - Status: Current - Products: Allison 250-C20/250-C20B engine (Siam Hiller Holdings STC SH177WE or 2 others) - Effective: November 20, 1980 - Superseded by: Nothing supersedes this AD - Product type: Appliance - Amendment: 39-3971 - Registered aircraft: 540 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/9173F91E238CFD3686256A390068371C.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/80-23-02 ## The airworthiness directive 80-23-02 SOLOY CONVERSIONS, LTD: Amendment 39-3971. Applies to Hiller UH-12D, UH-12E (including 4 place) and Bell 47G series helicopters certificated in all categories which have been converted to turbine power under Soloy Conversions, Ltd. Supplemental Type Certificates SH177WE, SH178WE and SH657NW respectively. Compliance required within 25 hours time-in-service or 30 days, whichever occurs first after the effective date of this AD. To prevent failure of Soloy transmission oil lubrication jets which may result in complete transmission failure and possible loss of the aircraft: 1. Inspect all Soloy transmission oil lubrication jets in accordance with the following Soloy Service Bulletins: a. Soloy/Hiller UH-12D and UH-12E (including 4 place): 14-560 dated October 20, 1980, or later FAA Approved revisions. b. Soloy/Bell 47G series: 14-660 dated October 20, 1980, or later FAA Approved revisions. 2. Replace defective jets before further flight. Equivalent methods of compliance may be used when approved by the Chief, Seattle Aircraft Certification Area Office, 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 Soloy Conversions, Ltd., Post Office Box 60, Chehalis, Washington 98532. These documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington 98108. This amendment becomes effective November 20, 1980. ## Affected data sheets (4) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS 2H3](https://openairdocs.org/tcds/2H3): Scott's-Bell 47 Inc; names 11 of 11 models: 47G-2A, 47G-3B, 47G-3, 47G-4A, 47G-5A, 47G-5, 47G-3B-2A, 47G-3B-2… - [TCDS H-1](https://openairdocs.org/tcds/H-1): Scott's-Bell 47 Inc; names 2 of 9 models: 47G-2, 47G - [TCDS 4H10](https://openairdocs.org/tcds/4H10): Siam Hiller Holdings Inc.; names 1 of 1 models: UH-12D - [TCDS 4H11](https://openairdocs.org/tcds/4H11): Siam Hiller Holdings Inc.; names 1 of 2 models: UH-12E ## 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: 540 (540 by airframe model, 0 by engine model) - Makers: Bell 400, Hiller 125, Bell-K-Copter 3, Hiller-Osborn 2, Bell-Carson 1, Bell-Huddleston And Wilson 1, Bell-Intermountain 1, Bell-Olympic Helicopters 1, Bell-Shippey 1, Bell-Tellijohn 1 Models with the most aircraft: - [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e): 103 aircraft (airframe model) - [Bell 47G-2](https://openairdocs.org/model/bell-47g-2): 87 aircraft (airframe model) - [Bell 47G-3B-1](https://openairdocs.org/model/bell-47g-3b-1): 86 aircraft (airframe model) - [Bell 47G](https://openairdocs.org/model/bell-47g): 55 aircraft (airframe model) - [Bell 47G-5](https://openairdocs.org/model/bell-47g-5): 40 aircraft (airframe model) - [Bell 47G-3B-2](https://openairdocs.org/model/bell-47g-3b-2): 26 aircraft (airframe model) - [Hiller UH-12D](https://openairdocs.org/model/hiller-uh-12d): 22 aircraft (airframe model) - [Bell 47G-4A](https://openairdocs.org/model/bell-47g-4a): 20 aircraft (airframe model) - [Bell 47G-2A](https://openairdocs.org/model/bell-47g-2a): 19 aircraft (airframe model) - [Bell 47G-5A](https://openairdocs.org/model/bell-47g-5a): 19 aircraft (airframe model) - [Bell 47G-3B](https://openairdocs.org/model/bell-47g-3b): 15 aircraft (airframe model) - [Bell 47G-2A-1](https://openairdocs.org/model/bell-47g-2a-1): 13 aircraft (airframe model) - [Bell 47G-4](https://openairdocs.org/model/bell-47g-4): 13 aircraft (airframe model) - [Bell 47G3B2A](https://openairdocs.org/model/bell-47g3b2a): 7 aircraft (airframe model) - [Bell-K-Copter 47G](https://openairdocs.org/model/bell-k-copter-47g): 2 aircraft (airframe model) - [Hiller-Osborn UH-12D](https://openairdocs.org/model/hiller-osborn-uh-12d): 2 aircraft (airframe model) - [Bell-Shippey BELL 47G](https://openairdocs.org/model/bell-shippey-bell-47g): 1 aircraft (airframe model) - [Bell-Carson 47G](https://openairdocs.org/model/bell-carson-47g): 1 aircraft (airframe model) - [Bell-Tellijohn 47G-2](https://openairdocs.org/model/bell-tellijohn-47g-2): 1 aircraft (airframe model) - [Bell-Intermountain 47G-3B-1](https://openairdocs.org/model/bell-intermountain-47g-3b-1): 1 aircraft (airframe model) All 30 models: https://openairdocs.org/ad/80-23-02/models.md Every aircraft: https://openairdocs.org/ad/80-23-02/aircraft.md ## Related documents - [STC SH177WE](https://openairdocs.org/stc/SH177WE): Installation of Allison 250-C20/250-C20B engine and related changes.. Siam Hiller Holdings Inc, Named in the applicability - [STC SH178WE](https://openairdocs.org/stc/SH178WE): Installation of Allison 250-C20/250-C20B engine and related changes. (UH-12E-L (4 place)). Siam Hiller Holdings Inc, Named in the applicability - [STC SH657NW](https://openairdocs.org/stc/SH657NW): Installation of Allison 250-C18A, -C18C, -C20, -C20B engine and related changes.. Siam Hiller Holdings Inc, 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.