- 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.
Copies of the files this page was built from, with their SHA-256. Retrieved October 18, 2026.
| File | Size | SHA-256 | Original |
|---|---|---|---|
| FAA DRS HTML | 23 KB | af454cfc…e231aab | FAA DRS (API key needed) |
On this page
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.
| 1947 | 3 |
|---|---|
| 1948 | 2 |
| 1951 | 1 |
| 1952 | 5 |
| 1953 | 6 |
| 1954 | 7 |
| 1955 | 4 |
| 1956 | 17 |
| 1957 | 17 |
| 1958 | 20 |
| 1959 | 14 |
| 1960 | 17 |
| 1961 | 14 |
| 1962 | 24 |
| 1963 | 19 |
| 1964 | 27 |
| 1965 | 24 |
| 1966 | 33 |
| 1967 | 27 |
| 1968 | 20 |
| 1969 | 12 |
| 1970 | 8 |
| 1971 | 12 |
| 1972 | 14 |
| 1973 | 11 |
| 1974 | 4 |
| 1975 | 5 |
| 1976 | 8 |
| 1977 | 4 |
| 1978 | 3 |
| 1979 | 4 |
| 1980 | 4 |
| 1981 | 4 |
| 1982 | 3 |
| 1993 | 1 |
| 1996 | 1 |
| 2010 | 1 |
140 with no year recorded