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

SA4-1427

Pratt & Whitney R-985 Series engines modified for fuel injection. Held by Bendix Aviation Corporation, which holds 5 approved modifications in all. Last revised January 1, 1960. System: engine.

What it applies to

Kind of product
Aircraft
Design holder
Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company
Models
Army AT-11, C18 Series, C-45 Series
Type certificates
A-2-582, A-757, A-765
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.