- Published
- December 4, 1956
- Issued
- December 4, 1956
- Model
- PA-22
- Data sheet
- TCDS1A6
- Registered aircraft
- 277 matched by model
- Product
- Aircraft · Small airplane
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 November 21, 2025.
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 | 33a5b8d1…f83505a | FAA DRS (API key needed) |
On this page
The airworthiness directive
55-08-04 PIPER: Applies to Model PA-22 Serial Numbers 22-1621 Through 22-1625, 22-1627, 22-1630, 22-1633, 22-1634, 22-1637.
Compliance required as soon as possible but not later than July 1, 1955.
The Hypass No. 48P6 ignition filters should be removed from the magnetos and replaced with magneto filter, Piper No. 63149 (Lear) obtainable from the Piper Service Department. It has been found that the Hypass No. 48P6 filters short and ground out the magnetos when subjected to a temperature which has been reported to be equal to the engine accessory temperature after a series of takeoffs have been performed.
Affected TCDS · 1
The type certificate data sheets for the models this AD names, matched by model and maker.
Registered aircraft · 277
Registered aircraft whose airframe or engine model this AD names. Matched by model only, so check each against the AD’s applicability.
| 1950 | 1 |
|---|---|
| 1951 | 61 |
| 1952 | 43 |
| 1953 | 48 |
| 1954 | 23 |
| 1955 | 20 |
| 1956 | 10 |
| 1958 | 3 |
| 1959 | 4 |
| 1961 | 3 |
| 1963 | 1 |
60 with no year recorded