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

ST89CH

Installation of Fairchild Model F800 or F1000 digital flight data recorder. Held by Abx Air Incorporated, which holds 64 approved modifications in all. Last revised December 21, 1993. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation; McDonnell Douglas Corporation
Models
DC-9-14, DC-9-51, DC-9-41, DC-9-34F, DC-9-34, DC-9-33F, DC-9-32F, DC-9-32, DC-9-31, DC-9-21, DC-9-15, DC-9-13, DC-9-12, DC-9-11, DC-9-15F
Type certificates
A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE, A6WE
On this site
Douglas DC-9 7 registered
Mcdonnell Douglas DC-9 93 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 8, 2026.