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

SA2302SO

Replacement of Cleveland brake discs, P/N 164-26A, or 164-126A, with Appalachina 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
Rust Robert E.; Rust Robert E.; Rust Robert E.
Models
DH.C1 Chipmunk 21, DH.C1 Chipmunk 22, DH.C1 Chipmunk 22A
Type certificates
A44EU, A44EU, A44EU
On this site
Dehavilland DHC-1 105 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.