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

SE4601SW

Modify intake and exhaust valves. Held by Daily Tubbs Aero, INC. Last revised February 9, 1982. System: engine.

What it applies to

Kind of product
Engine
Design holder
Olson George Company; Olson George Company
Models
Scarab Series 40, Scarab Series 50
Type certificates
E-2, E-2
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 8, 2026.