Unit Provides Enhanced Safety For High Work-Load IFR Environments

Avidyne Corporation has announced the Lincoln, MA-based company has received an amended Supplemental Type Certificate (STC) approval for their recently-certified DFC90 Digital Flight Control System which enables speed-based Flight Envelope Protection.

Flight Director Underspeed Condition

This new feature is designed to eliminates inadvertent autopilot–induced over-speed situations when autopilot is engaged. For flight envelope protection, available lift and speed margin are calculated constantly in the background whenever any modes, including Flight Director, are in operation. Overspeed is handled with anticipation and minimal but effective inputs. In Flight Director modes, actions appear as guidance cues with corrections blended into the "V-bar" commands.

“The certification of Flight Envelope Protection is a significant achievement for Avidyne, as well as a considerable step forward in general aviation autopilot performance and safety,” said Avidyne President and CEO, Dan Schwinn. “Avidyne is committed to continuously enhancing safety for all of our customers, and Flight Envelope Protection as well as the Straight and Level function and other capabilities of the DFC90 establish a new watermark in general aviation autopilot performance and safety.”

The DFC90 is an attitude-based digital autopilot system that is designed as a slide-in replacement for the S-TEC55X autopilot in existing Entegra-equipped Cirrus SR20 and SR22 aircraft.  The significant performance and safety benefits of the attitude-based DFC90 make it a very attractive upgrade for the more than 4,000 owners of Entegra-equipped Cirrus aircraft.  

Avidyne’s speed-based Flight Envelope Protection virtually eliminates autopilot-induced stalls (underspeed) and overspeeds, which lead to a significant number of GA accidents. With Flight Envelope Protection, the autopilot avoids exceeding the flight envelope while providing visual and aural warnings to the pilot.

The new Indicated Airspeed Hold (IAS) vertical mode includes a dedicated Airspeed knob and a new airspeed bug on the PFD, and provides a more elegant way to make Flight Level changes. The “Straight & Level” button overrides all autopilot modes and levels the aircraft in both pitch and roll from a wide range of capture attitudes for an added measure of safety. The Flight Director capability of the DFC90 is vastly improved and greatly improves the ability to hand-fly approaches.

According to Schwinn, ease of installation and transition is one of the DFC90’s attractive features.  It is simply a “box swap” or slide-in replacement for existing rate-based STEC 55X flight computers which means much lower installation costs.

Upgrading to the DFC90 only requires existing EXP5000 PFDs be updated to Release 8.0 (hardware & software). The Release 8.0.2 software and Mod 55 PFD hardware upgrades enable the DFC90 autopilot to take advantage of the precision attitude information of Entegra’s integrated Air Data and Attitude Heading Reference System (ADAHRS), without the need for costly wiring changes to the aircraft.

Another desirable trait is the unit’s robust data recording capability. “What you hear often is ‘I was flying along and it did x and it hasn’t done it since,’” explained Schwinn.  “And until now, there’s nothing you can do about that when you’re in a diagnostic situation.  Our autopilot has an extensive fault lining capability and we have the ability to take the data and go back and retrace the exact event that occurred during the flight.”

DFC 90

Schwinn adds the product has a number of forward-facing as well as back-end improvements.

The new Indicated Airspeed Hold (IAS) vertical mode includes a dedicated Airspeed knob and a new airspeed bug on the PFD, and provides a more elegant way to make Flight Level changes.

The “Straight & Level” button overrides all autopilot modes and levels the aircraft in both pitch and roll from a wide range of capture attitudes for an added measure of safety. The Flight Director capability of the DFC90 is vastly improved and greatly improves the ability to hand-fly approaches.

FMI: www.avidyne.com