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

SA4-444

Carburetor and cabin hot air muff with replaceable air inlet and outlet. Held by Raymen Peter H. Last revised January 1, 1960. System: engine.

What it applies to

Kind of product
Aircraft
Design holder
American Champion Aircraft Corp.; American Champion Aircraft Corp.; American Champion Aircraft Corp.; American Champion Aircraft Corp.
Models
7 Series, 11AC, S11AC, 11BC
Type certificates
A-759, A-761, A-761, A-761
On this site
Aeronca S11 9 registered
American Champion Aircraft 7 Citabria and Champ 429 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 20, 2026.