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

ST00411LA

Installation of Honeywell Traffic Alert and Collision Avoidance System (TCASII). Held by Acss (Aviation Communication and Surveillance Syst, which holds 33 approved modifications in all. Last revised August 16, 2005. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
The Boeing Company
Models
747-400 Series
Type certificate
A20WE
On this site
Boeing 747 192 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.