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

SA8509SW-D

Installation of a Century yaw damper system, Model YK1033 consisting of a Century Yaw Damper Bulletin2093. Held by Century Flight Systems INC, which holds 765 approved modifications in all. Last revised April 4, 1996. System: flight controls.

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; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company; Raytheon Aircraft Company
Models
C-45G, D18S, E18S-9700, TC-45J, G18S, TC-45H, C-45H, TC-45G, H18, D18C, UC-45J (SNB-5), E18S
Type certificates
A-765, A-765, A-765, A-765, A-765, A-765, A-765, A-765, A-765, A-765, A-765, A-765
On this site
Beechcraft E18 58 registered
Beechcraft TC-45 7 registered
Beechcraft UC-45 9 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 5, 2026.