While many in the aviation industry bemoan the fact that older aircraft values are rapidly declining, there is a bright spot, older efficient airframes with plenty of life left that can benefit from avionics upgrades. A great example is the Twin Commander twin-engine turboprop series. Twin Commander service center Eagle Creek Aviation of Indianapolis, Ind. (Booth No. 5385) has been working on a supplemental type certificate (STC) Garmin G1000 upgrade to the Twin Commander series for more than six months and expects to receive FAA approval in the second quarter of next year, according to Eagle Creek CEO Matt Hagans.

There are still more than 700 Twin Commanders flying worldwide and more than 300 in the U.S., according to Twin Commander Aircraft president Matt Isley. Twin Commander 690 through 1000 series were produced between 1973 and 1986, and Twin Commander Aircraft is now owned by Firstmark of Richmond, Va.

The Eagle Creek G1000 upgrade is the first time Garmin has incorporated engine instrumentation for the Honeywell (formerly Garrett) TPE331. The Twin Commander G1000 doesn’t use Garmin’s autopilot but retains the Meggitt autopilot found in many of these airplanes. “The original concept was to put in the Garmin autopilot,” Hagans said, “but that would have delayed certification by another year.” The Meggitt autopilot did have to be moved, because the mode annunciators need to be in the pilot’s field of view. Because there wasn’t enough depth at the top of the instrument panel, the autopilot control was moved to the glareshield.

Removal of the typical Collins or King avionics installed in most Twin Commanders and installing the Garmin system results in a net weight reduction of 250 pounds, according to Hagans. “All of the navcoms, radar, autopilot components, inverter system, all legacy avionics and sensors are gone and replaced,” he said. The G1000 system also will include Garmin’s new GWX 70 solid-state radar, a new radar altimeter, an electronic standby instrument and XM WX satellite weather. All of the engine sensors are new, too. The G1000 displays are two 10-inch PFDs and a 12-inch MFD. Larger displays don’t fit because of the limited panel space in the Twin Commander. “It features great visibility by having a very low glareshield,” said Hagans.

The Twin Commander G1000 STC will be owned by Eagle Creek, but it will be available for all Twin Commander service centers to offer their customers. Eagle Creek also offers a Garmin G600 upgrade for the Twin Commander series. Eagle Creek is showing the G1000-upgraded Twin Commander at the NBAA static display at Orlando Executive Airport. Pricing for the G1000 upgrade is “competitive with King Air installations,” Hagans said, and will be available from Eagle Creek during the NBAA convention.