EAA Sport Aviation - April 2012

so far beyond the capabilities of the old days
of mechanical gyros…frankly, it’s unthink-
able to even ask that question.”
Jim said there would be nothing “mate-
rial” to be gained from the certification
process—and he’s a man who’s been through
it many times. He does hold out hope that the
FAA will make it easier to certify an autopilot
such as his. “The FAA would like to see mod-
ern autopilot technology in a simplified
approval process,” he said. Then he added:
“We are autopilot people, and we built a safe
autopilot. We police ourselves. We supply the
muscle that accompanies the Garmin G3X
[EFIS for light-sport and experimental air-
craft]. In two to three years, the FAA may
relax the requirements for certification some-
what. But for now, the cost is prohibitive.”
Massachusetts-based Avidyne is bucking
that cost barrier, however, with its DFC90

digital autopilot. Originally designed to interface with the company’s Entegra EFIS and its ADAHRS, the DFC90 is a feature-rich digital autopilot that includes the most advanced functions found in integrated autopilot systems. It includes features such as the “straight and level” button ( sometimes called the “panic” button) that will return the aircraft to stable flight, flight envelope protection, and full-time flight envelope alerting that will alert the pilot to impending stalls or overspeeds even when the autopilot is not engaged. Among the newest features is IAS (indicated airspeed) mode, used in climb or descent to capture a specified altitude, but with the airspeed “bugged.” That eliminates the danger of stalling or overspeeding by adjusting the pitch attitude to hold the airspeed rather than vertical speed.

If you own a Cirrus or other Entegra-equipped airplane, the DFC90 is available now as a direct slide-in replacement for the S-TEC, and the price is affordable at less than $10,000. But the big news is that the DFC90 will soon be available for Cessna 182s and Beech Bonanzas and Barons equipped with Aspen Avionics Evolution EFD1000 primary flight display. Aspen is currently performing testing to make its PFD “emulate” the Avidyne Entegra system for the autopilot, so an affordable digital autopilot could be here soon for owners of legacy airplanes. And the FAA appears to be on board with the certification program.

Mark Phelps, EAA 139610, is an aviation writer living in New Jersey. He is the former editor of EAA’s Vintage Airplane magazine and the owner-pilot of a 1954 Beechcraft Bonanza.