- Models
- 47, 47B, 47B3, 47D, 47D1, 47E and 18 more
- Registered aircraft
- 490 matched by model
- Product
- Aircraft · Rotorcraft
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 | 19 KB | 7905f09b…bf6eaef | FAA DRS (API key needed) |
On this page
The airworthiness directive
56-05-01 BELL: Applies to Model 47 Helicopters: Model 47D1 Serial Number 477 and Subsequent, Model 47G Serial Numbers 667 Through 692, 694 Through 1511, Model 47G2 Serial Numbers 1342 Through 1418, Model 47H1 Serial Numbers 1347, 1349 Through 1356, 1358, and 1360, All Model 47 Modified to Include 47-644-172-3 Tail Rotor Extension Drive Shaft and All 47-644-172-3 Shafts in Stock.
Compliance required by March 1, 1956.
As a result of manufacturing error some Bell Model 47 tail rotor extension drive shafts P/N 47-644-172-3 were bored too deep resulting in a weakened wall section. Bell has issued Service Bulletin No. 106 requiring an immediate mandatory inspection by X-ray or by method described in the Service Bulletin.
This supersedes telegraph AD of February 3, 1956.
Affected TCDS · 3
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 490
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1946 | 1 |
|---|---|
| 1947 | 10 |
| 1948 | 5 |
| 1949 | 3 |
| 1950 | 2 |
| 1951 | 7 |
| 1952 | 8 |
| 1953 | 8 |
| 1954 | 9 |
| 1955 | 7 |
| 1956 | 19 |
| 1957 | 18 |
| 1958 | 18 |
| 1959 | 10 |
| 1960 | 10 |
| 1961 | 9 |
| 1962 | 12 |
| 1963 | 20 |
| 1964 | 18 |
| 1965 | 20 |
| 1966 | 33 |
| 1967 | 28 |
| 1968 | 20 |
| 1969 | 12 |
| 1970 | 8 |
| 1971 | 12 |
| 1972 | 14 |
| 1973 | 10 |
| 1974 | 4 |
| 1975 | 2 |
| 1976 | 1 |
| 1979 | 1 |
| 1980 | 1 |
| 1981 | 1 |
| 2010 | 1 |
128 with no year recorded