Avidyne debuts Flight Envelope Protection

Avidyne Corp. has revealed that its new DFC90 and DFC100 autopilot systems will include Avidyne Autopilot Flight Envelope Protection, a safety-enhancing feature that prohibits inadvertent autopilot–induced stall and overspeed situations. The DFC90 and DFC100 also include a “Straight & Level” button that overrides all autopilot modes and levels the aircraft in both pitch and roll for an added measure of safety in the event of an unusual attitude or other emergency situation.

“After thorough examination of the NTSB safety data for Cirrus aircraft, we found that autopilot-induced flight envelope exceedances, particularly stall/spin incidents in altitude hold or vertical speed climb modes, are a common error and contributing cause in more than 28% of all Cirrus accidents over the past eight years,” said Steve Jacobson, Avidyne’s vice president of product management. “Envelope protection provides pilots with an added measure of safety, which can be especially vital in high work-load IFR environments where pilots might be easily distracted.”

For envelope protection, available lift and speed margin are calculated constantly in the background whenever any mode, including Flight Director modes, are in operation, Avidyne officials explain. As the aircraft approaches stall, the autopilot gradually reduces maximum bank and vertical speed just enough to keep the wing flying, while visually and audibly annunciating the condition to the pilot. As a result, departure from controlled flight is prevented with the least impact on achieving mission-level objectives like navigation, climb or approach. Overspeed is handled similarly, with anticipation and minimal but effective inputs. In Flight Director modes, all these actions appear as guidance cues with corrections blended into the “V-bar” commands.

The DFC90 and DFC100 are attitude-based Digital Flight Control System systems currently targeted as slide-in replacements for the STEC 55X in Entegra- and Entegra Release 9-equipped Cirrus aircraft. They each have all the standard vertical and lateral modes of operation of a turbine-class autopilot system, including Flight Director (FD), Altitude Hold (ALT), Airspeed Hold (IAS), Vertical Speed Hold (VS), Heading (HDG), and Navigation (NAV, LOC/GS, GPSS/Vectors). They also include Avidyne’s “Straight & Level” button which overrides all autopilot modes and levels the aircraft in both pitch and roll for an added measure of safety.

Flight Envelope and Overspeed Protection are a standard features of the DFC90 and DFC100 autopilots. The DFC90 & DFC100 systems are scheduled for certification and delivery in mid-2010.

The retail price of the DFC90 for Entegra-equipped Cirrus aircraft is $9,995 and requires Entegra PFD Software Release 8.0. The retail price of the DFC100 for Entegra Release 9-equipped Cirrus aircraft is $14,995.

For more information: Avidyne.com.