The U.S. aircraft register, updated daily
Approved modifications · supplemental type certificate · historical · surrendered

ST00389LA-D

Installation of first class seats with GTE Airfone handset. Held by Hollingsead International, which holds 124 approved modifications in all. Last revised June 23, 2009. System: cabin, seats and restraints.

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
Models
DC-9-31, DC-9-32, DC-9-33F, DC-9-34, DC-9-82, DC-9-83
Type certificates
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 7, 2026.