SA1421SO
Installation of 40:1 gear ratio wing flap transmissions and related changes in accordance with Colemill Enterprises, Inc., Installation Instructions dated February 16, 1983, or later FAA approved revision. This modification provides and equivalent means of compliance with paragraphs (a)1, (a)2, and (a)4 of AD 82-27-13 and restores the 40 (full) flap travel. Held by Mike Jones Aircraft Sales INC., which holds 19 approved modifications in all. Last revised February 10, 2011. System: flight controls.
What it applies to
- Kind of product
- Aircraft
- Design holder
- Piper Aircraft Inc.; Piper Aircraft Inc.; Piper Aircraft Inc.; Piper Aircraft Inc.; Piper Aircraft Inc.
- Models
- PA-31, PA-31-300, PA-31-325, PA-31-350, PA-31P
- Type certificates
- A20SO, A20SO, A20SO, A20SO, A8EA
- On this site
- Piper PA-31 Navajo and Chieftain 935 registered
- The FAA's record
- On the FAA's site
What an approved modification is
A supplemental type certificate is the FAA's approval of a change to a certified design: a new engine or propeller, avionics, an autopilot, floats, a parachute, a larger fuel tank, an ice-protection kit. The company holding it may sell the kit and the paperwork to owners of the listed models; the modification then becomes part of that aircraft's record. The FAA's list says what was approved and for which models, not how many aircraft carry it.
Source: FAA supplemental type certificates (Dynamic Regulatory System). Register counts from the FAA register of October 12, 2026.