Piper PA-22 Instrument Panel Modification STC

Subject: Modifications to Tri-Pacer and Colt instrument panels to use modern 3-1/8" instruments per STC-SA00428SE.

Download PDF: PA22-Instrument-Panel-Modification.pdf

PA-22 Instrument Panel Modification


The later model Tripacers and Colts have a full gyro panel, identified by the raised portion on the L/H side. The production instrument panel was designed to accommodate the AN style instruments available at the time the airplanes were produced. Structural tubing behind the panel complicates the installation of deep instruments (such as a DG) low in the panel, hence the odd configurations seen in many airplanes.

Design Features

This modification (STC SA00428SE) upgrades the panel to use modern 3-1/8" instruments. It raises the location of all instruments and allows for the installation of typical DGs in the center of the "T" below the artificial horizon.

The modification has provisions for (7) 3-1/8" instruments and (1) 2-1/4" instrument. The cutouts for the horizon and turn coordinator allow for leveling to correct for any installation misalignment.

In the event the airplane is to be returned to the production configuration, this can be done in a manner which closely matches the original.

The Kit

The kit consists of a panel overlay with cutouts for the instruments. Placards and mounting hardware together with installation instructions and drawings are included.


The installation requires trimming the existing panel, deburring and touching up the trimmed areas and the installation of nut plates. No structural tubing needs to be cut.


After installing the modification, a Form 337 must be completed and signed by an AI confirming that the installation was done per the STC. A record of each aircraft modified will be kept.

The installation of new 3-1/8" instruments is not a part of this STC and will require a separate Form 337.

Kit for PA-22-150/160 .............. P/N .................... 92WD005100-1

Kit for PA-22-1 08 Colt ............. P/N ................ 92WD005100-501