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

SA2297SO

Replacement of Cleveland brake discs, P/N 164-26A or 164-126A, with Appalachian Accessories' stainless steel brake discs, P/N 75-27. Held by Appalachian Accessories, which holds 45 approved modifications in all. Last revised April 18, 1988. System: landing gear.

What it applies to

Kind of product
Aircraft
Design holder
The Cessna Aircraft Company; The Cessna Aircraft Company; The Cessna Aircraft Company; The Cessna Aircraft Company; The Cessna Aircraft Company; The Cessna Aircraft Company
Models
172B, 172, 172C, 172E, 172A, 172D
Type certificates
3A12, 3A12, 3A12, 3A12, 3A12, 3A12
On this site
Cessna 172 Skyhawk 20,669 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.