After a touch-and-go, I hand-flew the next one, and even though we turned in a little tight, I was able to rescue a slightly too high and too fast approach (under totally visual conditions with a safety pilot, mind you) flying the clear indications on the EFD1000 like a glideslope throughout the vertical nav approach. It is a serious and capable system.
Without going into too much minutia about which button to push to do what, suffice it to say that the design and the layout of the physical controls are just as well thought out as the symbology.
A pair of concentric knob buttons located along the bottom of the display control the inputs. The one on the right, for instance, allows you to enter the baro setting, set bugs and change heading. Just tap on the inner knob to go to the next function. It cycles through, so you never have to go backward, and the selection resets to "heading" after a few seconds of no input. The left-hand knob allows you to input the course or airspeed bug and to sync the various settings. It's easy to figure out.
Along the right side of the instrument are several small, vertically oriented keys that are only slightly less readable than the concentric knobs. They allow you to perform common tasks, such as decluttering the screen, inputting approach minimums or toggling between the 360 and arc modes on the HSI. The labels are a little small here, but once you know what you're looking for, they're easy to spot and punch.
The rest of the operation, really, is coordinating the use of the autopilot and the navigators with the PFD, which is little different than with the big glass Avidyne displays in the Cirrus I normally fly.
Do I prefer the large glass? I do. Would I be elated to have had an EFD1000 in my old Cherokee Six instead of steam gauges? There's no question about it.
There are actually several big ideas behind the EFD1000, but arguably the biggest is the way in which it's installed, by removing the two main flight instruments, the HSI and the attitude indicator, and plugging the EFD into the space that results. The LCD sits flat on the top of the panel surface and the display's "can," the tin-can sized enclosure that contains the guts of the unit, goes into the hole vacated by the former attitude indicator.
The appeal to this approach will be apparent to anyone who has ever had to do surgery to the panel in their airplane: You don't need to cut metal to install the new display. Cutting new holes in the existing panel, moving instruments, rewiring instrument clusters and installing adapters all cause installation costs to increase precipitously. The Aspen approach either eliminates or greatly reduces the likelihood or cost and complexity of any of these operations.
In most installations, you keep most of your old instruments and just move a couple of them to new spots. In a typical job, the old mechanical HSI just goes away and the iron gyro attitude indicator moves over a row and serves as a backup, taking over the spot formerly occupied by the VSI.
With what Aspen refers to as a "one-tube" installation, namely, just the EFD1000 in the center column, the requirement, to paraphrase, is for there to be backup attitude and airspeed information within easy view of the pilot. For all intents and purposes, that means the AI and the airspeed need to go right next to the new PFD. Which is no problem, because there's no longer need for a VSI.
Once Aspen gets its multifunction display certified -- and it expects that to happen soon -- that instrument would, in most installations, provide all the redundancy required to get rid of the mechanical backups. That's because the MFD -- in addition to being a multifunction map unit, with engine instruments, weather, moving maps and more -- will be able to take on the job of reversionary PFD with the push of a button. And because it will have its own dedicated AHRS, air data and backup power supply, there would be no loss of function when going to the backup. Look for a full report on that product when it becomes available.
Like other factory-installed PFDs, the Aspen EFD1000 will work with WAAS navigators, displaying the glideslope-like vertical deviation indicator when an APV approach is active. It can also be configured to display the required WAAS GPS annunciations, in some cases saving owners the need to install external annunciators for WAAS.
There is the challenge of packing it all into the small space allotted. There's the computer board, processor, AHRS, the air data unit and all the associated jacks and wiring. And once it's all in there, you've got to keep it all cool. It's a tall order, but it seems to be working.
And there were, not surprisingly, some teething pains along the way. We've spoken to a couple of avionics shop owners who told us that some of the early installations were complicated and involved substantial extra time spent tracking down and fixing glitches. More recent installs, they said, have gone a great deal more smoothly.