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

SA401NW

Installation of a Beech P-35 instrument panel with modified lower panel for switches and circuit breakers. Held by Collins Aviation INC, which holds 15 approved modifications in all. Last revised February 2, 1977. System: instruments and avionics.

What it applies to

Kind of product
Aircraft
Design holder
Hawker Beechcraft Corporation
Models
H35
Type certificate
3A15
On this site
Beechcraft H35 224 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.