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

SA3130WE

Installation of a single or dual Litton LTN-72 INS or a single or dual LTN-72R INS/RNAV navigation system. Held by Northrop Grumman Systems Corporation, which holds 62 approved modifications in all. Last revised April 12, 2016. System: instruments and avionics.

What it applies to

Kind of product
Aircraft
Design holder
The Boeing Company; The Boeing Company; The Boeing Company; The Boeing Company
Models
727-100 Series, 727-100C Series, 727 Series, 727C Series
Type certificates
A3WE, A3WE, A3WE, A3WE
On this site
Boeing 727 37 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.