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

ST00394WI

Installation of a Universal Navigation Corp UNS-1B PLUS integrated flight management system with dual Trimble Navigation Ltd TASMAN P/Y code GPS sensors or a single Universal GPS 1200 GPS sensor. Held by Learjet INC, which holds 538 approved modifications in all. Last revised April 9, 1996. System: instruments and avionics.

What it applies to

Kind of product
Aircraft
Design holder
Learjet Inc.
Models
35A (C-21A)
Type certificate
A10CE
On this site
Learjet 35 161 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.