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

SA3027WE-D

Revise interior arrangement to twenty-one rows of coach seating in accordance with DAS-1-WE United Air Lines Drawing List No. COA 2-4826 dated April 26, 1976, or later FAA approved revisions. Held by United Airlines INC, which holds 520 approved modifications in all. Last revised November 30, 2011. System: cabin, seats and restraints.

What it applies to

Kind of product
Aircraft
Design holder
The Boeing Company
Models
DC-8-52
Type certificate
4A25
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 22, 2026.