AD 80-23-02

Airworthiness directive · Turbine Power Conversions · Allison 250-C20/250-C20B engine (Siam Hiller Holdings STC SH177WE or 2 others)

Effective
November 20, 1980
Models
UH-12D, 47G, 47G-2, 47G-2A, 47G-2A-1, 47G-3 and 10 more
Registered aircraft
540 matched by model
Product
Appliance
Amendment
39-3971

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

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 TCDS · 4

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

Registered aircraft · 540

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
  • Bell400 aircraft
  • Hiller125 aircraft
  • Bell-K-Copter3 aircraft
  • Hiller-Osborn2 aircraft
  • Bell-Carson1 aircraft
  • Other makers99 aircraft
By year built
19472010
Registered aircraft by year built: 400 aircraft
19473
19482
19511
19525
19536
19547
19554
195617
195717
195820
195914
196017
196114
196224
196319
196427
196524
196633
196727
196820
196912
19708
197112
197214
197311
19744
19755
19768
19774
19783
19794
19804
19814
19823
19931
19961
20101

140 with no year recorded

By model

See all 27 models

Aircraft

See all 540 aircraft