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

SA2020SO

Installation of Allied/Bendix Microwave Landing System MLS-21. (MU-300 Diamond I). Held by Alliedsignal Commercial Avionics Systems, which holds 14 approved modifications in all. Last revised December 5, 1986. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
Raytheon Aircraft Company
Models
MU-300
Type certificate
A14SW
On this site
Mitsubishi MU-300 17 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.