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

SE00048AT-D

Modification of compressor intermediate case diaphragm to permit acceptable of a 7th stage airseal ring. Held by Aero Component Technologies, which holds 7 approved modifications in all. Last revised January 5, 1994. System: engine.

What it applies to

Kind of product
Engine
Design holder
Pratt & Whitney Division; Pratt & Whitney Division; Pratt & Whitney Division
Models
JT8D-17AR, JT8D-17A, JT8D-15A
Type certificates
E2EA, E2EA, E2EA
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.