The U.S. aircraft register, updated daily
Approved modifications · supplemental type certificate · current · reissued

SA00798AT

Installation of left hand and right hand auxiliary tanks fuel cell assemblies. Held by Ffc Manufacturing, which holds 86 approved modifications in all. Last revised April 29, 2009. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
Piper Aircraft Inc.; Piper Aircraft Inc.; Piper Aircraft Inc.
Models
PA-31T, PA-31T1, PA-31T2
Type certificates
A8EA, A8EA, 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 7, 2026.