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

SA420EA-D

Relocate the L.A.S.I. Flight Data Recorder to the aft fuselage area at\nSta. 1462, utilizing a remote vertical accelefometer in the left wheel well.\nInstall a new auxiliary pitot tube and static ports for the flight recorder. Install a Flight Recorder/Communicaticn Unit. Held by American Airlines INC, which holds 377 approved modifications in all. Last revised January 7, 1972. System: landing gear.

What it applies to

Kind of product
Aircraft
Design holder
The Boeing Company; The Boeing Company
Models
707-100B Long Body, 707-100B Short Body
Type certificates
4A21, 4A21
On this site
Boeing 707 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 21, 2026.