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

SA4-1590

Riveted fuel tanks changed to welded wing and nose tank assemblies and gauge from mechanical to electric float type. Held by Met-Co-Aire, which holds 21 approved modifications in all. Last revised January 1, 1960. System: airframe structure.

What it applies to

Kind of product
Aircraft
Design holder
Univair Aircraft Corporation; Univair Aircraft Corporation
Models
F-1, F-1A
Type certificates
A-787, A-787
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 20, 2026.