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55-13-01: Idler Bellcrank Installation

FAA order 55-13-01 is an airworthiness directive published December 4, 1956. The FAA's subject line: Idler Bellcrank Installation. It names Piper PA-23 Apache and Aztec: about 1,315 aircraft on the U.S. register today, though an order usually covers particular versions or serial numbers rather than every one. System: flight controls.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Piper Aircraft Inc.
Models
PA-23
On this site
Piper PA-23 Apache and Aztec 1,315 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 (811 characters)
55-13-01 PIPER: Applies to Model PA-23, Serial Numbers 23-160 to 23-162 Inclusive, 23-166 to 23-168 Inclusive, 23-170, 23-172, 23-177, 23-193 to 23-219 Inclusive, 23-221 to 23- 224 Inclusive, 23-226 to 23-229 Inclusive, 23-231 to 23-234 Inclusive, and 23-237. Compliance required by August 1, 1955. It has been found that all the PA-23 Models listed above have installed two flexible fuel valve controls that have been found to flex excessively at the splice. The addition of an idler bellcrank should be accomplished by the use of Piper Kit No. 754 103 and the instructions included. Owners of PA-23's with auxiliary fuel tanks must not operate the auxiliary fuel system until this modification has been accomplished. (Piper Immediate Action Service Bulletin No. 139 applies to this malfunction.)

Related safety bulletins advice on the same designs, not orders

2018-11-21SW-18-31 · NAVIGATION, ATTITUDE, AND DIRECTION DATA SYSTEM
2017-02-21CE-17-08 · Main Landing Gear Drag Link Bolt
2012-09-17CE-12-44 · Exhaust systems
2008-01-09CE-08-11 · Landing Gear
2005-07-07CE-05-67 ·

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 November 6, 2026. Connections as data: /graph/directive/55-13-01.json · aircraft systems.