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

SA00271WI

Replacement of the hydraulic system pressure switch with a new switch. Held by Apph Wichita INC., which holds 2 approved modifications in all. Last revised November 8, 2007. System: electrical power.

What it applies to

Kind of product
Aircraft
Design holder
Cessna Aircraft Company; Cessna Aircraft Company; Cessna Aircraft Company
Models
F337G, F337H, F177RG
Type certificates
A23EU, A23EU, A26EU
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.