At the heart of the philosophy behind the KFD 840 is the question of what, exactly, a PFD is supposed to do. In Bendix/King's view, its job is to be a PFD, so its features are intentionally limited. There are no composite modes, no engine instruments, no weather overlays. It in essence just improves upon the performance and appearance of mechanical gauges while adding a few highly desirable features, like true airspeed and winds, for example.
There are some good things about this direct approach. For one thing, because the PFD is just a PFD, you get a full-sized AI and HSI, and in my book, size does matter, especially when hand-flying, because it allows you to more easily keep an eye on the horizon as you're attending to other duties around the cockpit.
Another big benefit is reliability, and it's hard to overstate this. If you're lucky, the life expectancy of a vacuum-powered attitude indicator is 1,000 hours. With solid-state ADAHRS, the mean time between failures is off the charts, and the redundancy of the systems, especially with the optional battery backup, is a huge improvement over most conventional vacuum powered.
While synthetic vision is not part of the initial package, there are a couple of value-added features the KFD 840 gives you today, namely, customizable checklists and a weight and balance calculator.
Checklists on the 840 are handy and easy to use. When you select the feature, the list pops up and the rest of the display is compressed into the left two-thirds of the screen, leaving it big enough while making the checklists large enough to read easily. Plus, the fact that the list is there on the PFD allows you to continue your scan more easily than when you're looking down into your lap or over to the MFD. It's a nice addition.
Another feature I love is the built-in weight and balance calculator. Like most pilots I do a weight and balance only when I have more than a couple of passengers and some bags; in other words, only when I think I might bump up against the limitations. With the utility on the KFD 840, you can do one every time you start up, if you so desire, and it's so easy to do, that even when you have a big load, all it takes is a minute or so to do the calculations. If you hate doing weight and balance calculations as much as I do, you'll like this feature a lot.
Even before you start up, you can pull up the utility. Select the different stations -- the airplane-specific weights and arms are set up by the shop using your POH -- and enter the weights for those stations. When you're done entering the weights for the people, bags and fuel, the system automatically displays the weight and balance solution graphically for you, showing you unambiguously whether you're inside the envelope or not. Nice.
Just Flying It
If there's one word that could sum up the idea behind the KFD 840, the word would be "simple," and that was exactly my impression on my first flight with it.
In terms of making sense of the PFD, there's really nothing to it. If you have experience with flat-panel PFDs, there's nothing new. The tapes, trend vectors, deviation indicators, bugs and windows are all thoroughly conventional (something that 10 years ago I never thought I'd be saying about glass panels in light airplanes). The learning curve for me on the PFD interpretation was very close to zero.
My impression of the physical display was very positive. It's bright, sharp, and the symbology is excellent (much of it clearly inspired by Honeywell's high-end Primus Epic flight displays).
In terms of button pushing, the transition was nearly as easy. The logic of it is different than for the Garmin G1000 or Entegra, but the bottom line is, even newbies should be able to figure it out on the fly. The menus are very shallow (in a good way), and because the soft keys are context sensitive, you're never more than a couple of pushes away from what you want.
Otherwise, the flying was pretty much what I'm used to doing every day in my PlaneSmart Cirrus G3 Turbo. I use the Garmin GNS 430s to manage the flight plan, traffic, nav and comm tuning, and instrument procedures. Again, I already know how to do all that. The learning curve here, again, was zero.
The 840 is compatible, says Bendix/King, with most GA autopilots. And the 840 does support flight director display. The 840 serves essentially as a repeater, displaying the flight director commands from the autopilot, if it generates flight director info.
Perhaps the most remarkable thing about the advent of retrofit flat-panel avionics systems is how different they are from each other and how competitive, at least in terms of price, they are with each other. The suggested price of the KFD 840 is $16,995, and Bendix/King has worked diligently to keep the install price as low as possible, too. There are no remote boxes, no converter boxes and no antennas to install. Even the magnetometer should be a relatively easy installation, as it will likely be able to use the same wiring as the existing flux-gate, if one is installed.
The 840 will enjoy some healthy competition from a couple of competitors, Aspen and Garmin, to name two. While the 840 has fewer features than those competitors, it does have the advantage of doing what it's designed to do very well. And Bendix/King makes it clear that there are product upgrades, including synthetic vision and more, on the way.
The KFD 840 is a PFD with somewhat limited features still, but the feature that matters most -- being a PFD -- is one that it excels at.
And for owners who already have a good navigator/MFD in the panel, it represents a way to upgrade the panel with solid-state attitude and air data, while being dirt simple to transition to, and at a price that even a few years ago seemed simply impossible.
And it does it while letting pilots continue to fly their airplanes exactly as they have in the past, except, that is, for a big piece of glass right in front of their eyes.