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

SA522SW

Installation of exhaust gas temperature (EGT), cylinder head temperature (CHT) components/ systems.\nAll aircraft equipped with reciprocating engines are elgible for the installation of the Alcor EGT and CHT component systems. Held by Alcor LLC, which holds 13 approved modifications in all. Last revised May 27, 2025. System: engine.

What it applies to

Kind of product
Aircraft
Design holder
Miscellaneous
Models
Miscellaneous
Type certificate
Miscellaneous
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 5, 2026.