55-08-04: Ignition Filter Replacement
FAA order 55-08-04 is an airworthiness directive published December 4, 1956. The FAA's subject line: Ignition Filter Replacement. It names Piper PA-22 Tri-Pacer and Colt: about 2,942 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: engine.
What it applies to as the FAA lists it
- Kind of product
- Aircraft
- Makes
- Piper Aircraft Inc.
- Models
- PA-22
- On this site
- Piper PA-22 Tri-Pacer and Colt 2,942 registered
Dates and paperwork
- Published
- December 4, 1956
- Docket
- Unknown
- Status
- Current
- The FAA's document
- Read the order on the FAA's site
The order itself the regulatory text, as published
Show the full text (619 characters)
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.
Related safety bulletins advice on the same designs, not orders
2018-11-21SW-18-31 · NAVIGATION, ATTITUDE, AND DIRECTION DATA SYSTEM
2005-07-07CE-05-67 ·
1998-10-21ACE-99-01 ·
Source: FAA Dynamic Regulatory System, airworthiness directives. The FAA's document is the authority; the register counts are this site's, from the FAA register of October 30, 2026. Connections as data: /graph/directive/55-08-04.json · aircraft systems.