Plane & Pilot
Tuesday, October 19, 2010

Advanced-Degree Autopilot

The DFC90 completes Avidyne’s integrated avionics suite with an increase in performance and safety

Avidyne’s exhaustive study of Cirrus accident data found almost one-quarter of all mishaps involved overspeed or underspeed conditions, situations Envelope Protection can help prevent. (Envelope Protection in the DFC90 is active whenever the autopilot is engaged; in future iterations it may be active at all times.)

The Straight and Level (S&L) button in the center of the DFC90 is another potential lifesaver. This is hardly the first autopilot with a panic button that promises to recover an aircraft from an unusual attitude, but Dr. George is unusually robust. The user guide calls for maximum engagement limits of 60 degrees of bank and 30 degrees +/- of pitch, but the S&L button reportedly has been demonstrated to work when engaged in an inverted Cirrus. When S&L is engaged, the autopilot commands an unloaded roll and a 2.5 G pitch-up recovery.

The ideal demonstration of the DFC90’s rock-solid approach mode would be a WAAS approach in a bucking crosswind. Where the 55X is known for fishtailing its way to the runway on final, the DFC90 flies the airplane like it’s on a rail. But this was a fairly calm day and the panel wasn’t WAAS-enabled. The ILS 6 approach at Poughkeepsie (KPOU) nonetheless showed the autopilot’s deadeye aim. We looked straight down the runway from the moment the autopilot intercepted the final approach course more than six miles out, and other than getting larger, the target barely moved.

The Flight Director (FD) mode, which can be a struggle to use in the 55X owing to a jumpy command bar, is stable and functional in the 90. We hand-flew using the FD on our way back to HPN, and it made keeping the aircraft in the correct attitude for the desired flight path easy.

"Avidyne’s finally in the flight control world," Jacobson summed up after the flight. "The DFC90 and 100 are core to our business. They really flesh out the whole Avidyne product offering and make us a real player."

The next step in Avidyne’s autopilot evolution is certification of the DFC100 for Entegra R9 panels, both as a retrofit and in new installations. The R9 uses Avidyne’s own FMS, rather than the Garmin 430s that have driven all earlier Entegra releases. The all-Avidyne architecture will give the DFC100 better and more powerful capabilities, including VNAV, enabling it to fly vertical, as well as lateral approach segments. Going forward, synthetic vision will be added to the Entegra mix, along with as yet unannounced capabilities that Jacobson promises will be a "game changer."

Meanwhile, more than 250 DFC90s ($9,995) have already been sold into a fleet with several thousand upgradable Entegras. The retrofit requires an Entegra R8 system; earlier releases can be updated to R8 with a PFD hardware and software upgrade (about $3,000), easily accomplished by an authorized dealer in a couple of hours. (Avidyne has offered discounts for combo Entegra/DFC90 retrofits.) The autopilot swap itself is a slide-out/slide-in replacement, which takes "four minutes with a slow turning wrench," Jacobson said. "The idea is to have a drive-by replacement—the guy flies in, borrows the crew car, goes get lunch, comes back, and the plane is ready."

For legacy Entegra flyers looking for a giant leap forward in performance and safety from their Cirruses, the DFC90 is just what the doctor ordered.


Add Comment