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

SA3661NM

Installation of a Franklin 4AC-176-BA2 engine, cowling/baffling, engine mount and a Flottorp (Univair) 32K48E (Wood) propeller. Held by Laverne Tegland. Last revised December 10, 1986. System: propeller.

What it applies to

Kind of product
Aircraft
Design holder
Piper Aircraft Inc.
Models
J3C-65 (Army L-4; L-4A; L-4B (Navy NE-1); L-4H; L-4J (Navy NE-2))
Type certificate
A-691
On this site
Piper J-3 Cub 3,804 registered
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.