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FAA orders · airworthiness directive · current

79-26-01: Stabilator Skins and Frame

FAA order 79-26-01 is an airworthiness directive in force since December 24, 1979. The FAA's subject line: Stabilator Skins and Frame. 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: airframe structure.

What it applies to as the FAA lists it

Kind of product
Aircraft
Makes
Piper Aircraft Inc.
Models
PA-23-250, PA-23-250 (Navy UO-1)
On this site
Piper PA-23 Apache and Aztec 1,315 registered

Dates and paperwork

In force since
December 24, 1979
Published
December 17, 1979 (signed December 7, 1979)
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 (1,432 characters)
79-26-01 PIPER: Amendment 39-3639. Applies to Piper PA-23-250 Model airplanes, Serial Nos. 27-7654001 thru 27-7954044 certificated in all categories, which incorporate the following stabilators. Serial Nos.: 0336-L thru 0340-L 0401-L thru 0607-L 0337-R thru 0341-R 0402-R thru 0609-R To prevent possible loosening and relative motion between the stabilator bottom skins and the stabilator frame - structure, accomplish the following: a. Within the next 50 hours in service after the effective date of this AD, unless already accomplished within the past 50 hours and at intervals not to exceed 100 hours in service thereafter, inspect and repair or alter the left and right stabilator in accordance with the "INSTRUCTIONS" section on page 3 of 3 in Piper Service Bulletin No. 606 dated July 12, 1979, or approved equivalent. b. When the stabilator assemblies are altered in accordance with paragraph B.4. of the "INSTRUCTIONS" section or equivalent, compliance with this AD is no longer required. c. Equivalent inspections, repairs or alterations must be approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. d. Upon submission of substantiating data through an FAA Maintenance Inspector, the compliance time specified in this AD may be adjusted by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region. This amendment is effective December 24, 1979.

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 October 30, 2026. Connections as data: /graph/directive/79-26-01.json · aircraft systems.