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

SA3374WE

Installation of bearing P/N VTB02220 as replacement for Boeing P/N 10-60545-113S in main landing gear lock system assembly. Held by Valley-Todeco, INC, which holds 5 approved modifications in all. Last revised March 29, 1977. System: landing gear.

What it applies to

Kind of product
Aircraft
Design holder
The Boeing Company; The Boeing Company
Models
727-200 Series, 727-100 Series
Type certificates
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 9, 2026.