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

ST00149CH-D

Installation of an AlliedSignal CAS-66A Traffic Alert and Collision Avoidance System (TCAS I). Held by Electrosonics, which holds 76 approved modifications in all. Last revised May 1, 2000. System: instruments and avionics.

What it applies to

Kind of product
Aircraft
Design holder
Raytheon Aircraft Company; Raytheon Aircraft Company
Models
1900, 1900C (C-12J)
Type certificates
A24CE, A24CE
On this site
Beechcraft 1900 Airliner 157 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.