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

SA104GL

Installation of a 0.6 second time delay circuit in the side-slip warning system in accordance with Farrington Aircraft Corporation Drawing No. FAC-1001, revision D, and FAC-100, Page 3, revision C, and later approved revisions. Held by Heliplane Aircraft Corporation International, which holds 7 approved modifications in all. Last revised July 27, 2011. System: other and general.

What it applies to

Kind of product
Aircraft
Design holder
Air & Space America Inc.
Models
18A
Type certificate
1H17
On this site
Air & Space America Inc 18 6 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 7, 2026.