The Citation Sovereign I was hand-flying through the big rocks of northern Arizona on a pitch-black night was no run-of-the mill midsize Cessna. Intercepting the localizer for Prescott at 8,300 feet, an altitude that's hundreds of feet below the nearby peaks, I was glad for the Honeywell primary flight display staring me in the face.
It was like nothing I'd ever seen before in my life, and I liked it. I liked it a lot.
We in the aviation industry do a lot of talking about avionics, but when it comes right down to it, we seldom speak directly about what these instruments — which today are almost exclusively digital products of one kind or another — are intended to do. That goal, simply stated, is to make flying safer.
Bizjets and commercial airliners, however, are already so safe that there are very few accidents to prevent. And when there is an accident, the cause is often the kind of freak occurrence that's hard to predict or to do anything about once you know what to look for.
Still, there is room for improvement, and the target is that very small subset of accidents that still take place, often when the conditions are the most extreme — when the weather is rough. It's then that pilots might need the most help, such as in the crash of a Gulfstream III on approach to Aspen a decade ago in which pilots apparently at the last moment lost sight of the runway on a snowy night. Eighteen died in the crash.
Blended Technology
The Sovereign I was flying that night was equipped with Honeywell's latest developmental display technology designed to prevent accidents, like the one at Aspen, that result from pilots being unable to adequately see the landing environment.
Honeywell's technology is so new it doesn't have a name yet.
The idea is to blend together two existing methods for enhancing the pilot's natural vision. Those two are synthetic vision systems (SVS) and enhanced vision systems (EVS, or EFVS, for enhanced flight vision system). Though they were both little more than dreams 15 years ago, both synthetic vision and EFVS are fairly well-established in high-end business airplanes. Synthetic vision, in the form of Garmin's SVT, is commonplace on new piston airplanes and an increasing number of turboprop airplanes and jets.
You can think of "synthetic vision" as "computerized vision," and you'll have the basic idea. Because the airplane knows exactly where it is and because the terrain database knows exactly, well, almost exactly, what's out there, the system can create a computerized facsimile of what the world out there would look like in exact relation to the airplane — if it weren't dark outside or cloudy, that is.
As you can see in the accompanying photographs, synthetic vision makes for an impressive presentation. While no one would ever mistake it for the real world, which is actually a good thing, it very effectively mimics the look of the outside world without all the visual impediments, such as haze or dark of night.
The downside, of course, is that it's not the real world, so you can't, for instance, see a fuel truck on the taxiway or a mule deer dashing across the runway. You're stuck with a presumptive view of the world out there. Which is almost always good enough.
Honeywell's synthetic vision, which it calls SmartView, is an elegant and powerful implementation of the technology. The display maintains the existing PFD data, the attitude presentation with the HSI, along with all the performance instrument data: the vertical speed, altimeter and airspeed tape presentations. There are also autopilot annunciations, velocity vector display, trend vectors, navigation source annunciators and more. The point is that the PFD is a very busy place to begin with, never mind adding in the synthetic vision display upon which all the other data are superimposed. Somehow, Honeywell pulls it off beautifully.
The synthetic vision itself is remarkable. Not only does it give the pilot the general lay of the land, the hills and plains of the earth below, but there are also water features, colorings and shadings that bring that computerized world to life.
