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

SA946NW

Installation of squared-off wing tips. Held by Davison'S Air Service INC. Last revised June 11, 1980. System: airframe structure.

What it applies to

Kind of product
Aircraft
Design holder
Thrush Aircraft Inc.
Models
S-2R
Type certificate
A4SW
On this site
Thrush Aircraft Inc S-2 102 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 19, 2026.