I had an opportunity to fly the Entegra in a Cirrus SR22 that Avidyne is using for certification flight testing. The Entegra display replaces all six of the conventional primary IFR instruments and occupies about the same amount of space as the six three-inch dials we are all accustomed to seeing in a light airplane. An electric attitude gyro and standard pneumatic airspeed and altimeter instruments are mounted in the sub-panel below the Entegra to act as emergency backups.
The Entegra is wired to the main battery switches, not the avionics switch, because it is an essential piece of flight equipment. As soon as you turn on either battery-the SR22 has two-the AHRS in the Entegra begins its alignment process, which takes about three minutes during which the airplane should not be moved. Three minutes can seem like a long time, but during that period you must get the engine started, avionics on and set and complete other pre-taxi chores. The last 45 seconds of the alignment process are counted down on the Entegra screen with a reminder not to move the airplane. If the Entegra AHRS ever loses power in flight it can not realign until the airplane is stationary on the ground, and that is one of several obvious reasons that it has dual sources of electrical power in the SR22.
The Entegra is controlled by knobs on the lower corners of the unit. Eight buttons on the edges of the display select what function the knobs will change, such as altimeter setting, target altitude, course, heading bug, map range and so on. Display brightness is manually controlled by a rocker switch on the upper right corner.
The Entegra display symbology is similar to the PFDs common in jets. Airspeed and altitude are presented on vertical scales with a "rolling" digital display that gives you a subconscious impression of the rate of change of the digits. Vertical speed is shown on an arc scale on the right side. Slip-skid is displayed on the roll index triangle with the bottom portion of the triangle moving left or right to mimic the ball in a conventional slip-skid indicator.
The lower half of the display is devoted to heading, map, nav guidance, wind display and other lateral nav functions. The compass card can be displayed as a full circle, or as an arc with moving maps available, too. It's all pretty standard stuff well proven in the jets.
What is unusual about the first Entegra is a full-width blue-brown horizon display. This is a Cirrus Design choice and is a feature you are likely to either love or hate. I would rather have the horizon display confined between the airspeed and altitude tapes than have it move behind essential information such as airspeed and altitude. Also, by filling all of the space on the top half of the display with the blue-brown artificial horizon you end up with another line bisecting the entire display from the lower black background HSI area. In VFR conditions when you can look out at the horizon the wide artificial horizon display makes infinite sense, but in the clouds with no horizon, it makes less sense to me. But, as I said, you will either love or hate this feature.
