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

SE3877NM

Modification of a Lycoming O-235-L2C engine to increase the horsepower rating from 115 HP @ 2700 RPM to a continuous 125 HP @ 2800 RPM. Held by Kai V. Nielsen, which holds 2 approved modifications in all. Last revised January 8, 2008. System: engine.

What it applies to

Kind of product
Engine
Design holder
Textron Lycoming AVCO Corporation
Models
O-235-L2C
Type certificate
E-223
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.