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

SA1-135

Installation of 2003X series radome. (C-45H, C-45G, D18S WHEN MODIFIED PER SA3-279). Held by Norton Company, Performance Plactics, which holds 62 approved modifications in all. Last revised March 21, 1974. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company
Models
D18S, H18, C-45H, C-45G, G18S, E18S, E18S-9700
Type certificates
A-765, A-765, A-765, A-765, A-765, A-765, A-765
On this site
Beechcraft E18 58 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.