You have to envy big-iron drivers with all those navigation and weather displays, with overlays at the touch of a button, plus engine instruments, alarms, checklists, timers and lots more.
Why cant general aviation have some of those goodies? Well, we can. Sort of.
Our desire for electronic cockpit displays has not escaped the notice of several ingenious (and gutsy) entrepreneurs, who have developed lighter and sometimes better versions of big-iron flight deck computers aimed at the spam can market. Several manufacturers have jumped onto this bandwagon with an array of ideas and hardware to match. The question is: Is this concept in its current incarnation ready for prime time? What can you actually buy today? What does the future hold?
The basic idea is simple: Put a computer in the cockpit and then think of ways to use it to calculate and display everything the pilot needs. Wouldnt you love to just upload your flight plan from your home system to a panel system that has the same flight-planning software?
After all, the average laptop of today has about 20 times the computing power of the hardware the Apollo astronauts used to land on the moon. Designing it should be simple, right?
In fact, many of the problems are already solved. Most of the underlying software already exists. Laptops are light and sturdy and continue to get smaller, cheaper and better. Wire in a GPS and you have live position data with a slick moving map display with far more detail than any Boeing 777 has. Do you download weather maps from the Internet? Why not connect your cockpit computer to an aviation cellphone and do it in the air? Datalink services and the phone technology to support are coming together.
Finally, the data is there. The entire U.S. airspace, with all boundaries, altitudes limits, airways, airports and navigation sites and intersections fits on two CDs.
Not So Easy
So why hasnt it happened already? Three problems stymie progress: Computer hardware isnt designed for the cockpit; the software is meant for ground use not airborne use and the cockpit itself wasnt designed for a computer.
Laptops are designed for a tough environment. The latest tests of laptop systems, done by PC Computing Magazine (April 1997), include temperature and drop tests (several survived a drop off a 30-inch desk with no damage other than a chip or crack to the case).
For equivalent computer power, a laptop costs about $1000 more than a desktop and buys you that environmental robustness.
Vibration: Manufacturers assume you might drop a laptop but that you wont use the panel of your pick-up as a working surface. Consequently, the shake, rattle and roll found in a typical airplane is not in the design brief for standard computer equipment. It adds unnecessary complexity and cost.
Temperature: The labs test laptops for survival in extreme heat and cold; they dont try to run the computers in those environments before allowing them to warm to room temperature. A recent Antarctic expedition, for example, discovered that only a few of the laptops worked in the prevailing temperatures and even those had to be coddled and warmed to make the display usable.
Display: What good is all that compute power if you cant see the results? Many a laptop owner who has tried to telecommute from the backyard on a nice day has discovered that laptop displays dont cut it in direct sunlight.
Software: On your flight-planning software, click the mouse on the Open Flight Plan button, select the flight plan you want, and click OK. You want to add a waypoint, so you click the Add button, click on waypoint, then type in the waypoint name, click OK, and your flight plan is updated. Piece of cake.
Try that in the cockpit. Bouncing along through an area of bumpy cumulus, you request a route change away from the hills below, hoping you can get out of the chop before your passengers split their cookies. Center approves the request and now you have to update your cockpit computer, so you reach for the mouse and keyboard. Ooops, what mouse and keyboard?
Naturally, in the cockpit, text input and editing has to work with knobs and keys and perhaps other methods, such as soft function buttons (more on that later) or touch-screens. No big deal, you say? Maybe. But remember that new software code has to be written to make all that work and that code has to be tested to make sure its bug free with all of the software you plan to use. Groundbound software is often buggy, but who cares? Youll care more if that software is running your weather detection system.
And what about a crash? Not the airplane, the computer. On the ground, this elicits an obscene reference to the computers lineage and a quick stab at the reset button. But suppose it happens in the soup, right after Center calls and says theyve lost the radar, please advise your estimate for passing GASSE intersection. Worse yet, suppose the system wont reboot normally? If you havent had that pleasure, just wait.
Then theres the problem of where to put it. How many of us have a 7 X 5 inch area of unused panel space with about 12 inches of depth behind it? Could you create it? Sure, at a price. Just have your avionics shop move your radio stack around, maybe replacing one or two systems with smaller-footprint boxes in the process.
One solution to this is an independent portable system, which has its own set of problems, including powering it up easily, cables running to and fro and where to put the display.
Against this daunting backdrop of problems, several manufacturers have made significant progress. Our hats are off to them for succeeding as well as they have. Nonetheless, this equipment is not quite ready for prime time yet, in our view.
Whats Out There
A number of companies have dabbled in cockpit PCs, the three leaders for GA applications are Avidyne, Archangel and Technon. JPI, best know for its engine monitors, also offers a system. Avidyne is nothing if not persistent. Theyve been hammering away since 1994, pursuing their vision of a Multifunction Flight Computer (MFC). They showed it first at Oshkosh in 1995 to the admiring eyes of many show goers. Avidyne recently received a supplemental type certificate for both hardware and software but the equipment is not TSOd simply because there is no TSO for such systems.
The MFC has a 6.25 X 4 inch faceplate with an active matrix LCD mounted on the left side. It has nine buttons and two knobs on the right. Six of the buttons are soft function keys aligned vertically to the right of the screen. A soft button doesnt have a single function but its function is determined by the software. You can bring up a menu on the screen next to the line of soft buttons to tell you what each one does at any moment.
Electronically, the Avidyne system is a standard IBM-compatible with a 486 processor. Physically, the motherboard fits around the sides of the case, with room for expansion boards and the display in the center. It includes both a heater for cold days and a fan for operations at normal temperatures. The hard disk is a standard laptop unit, but its mounted in a custom vibration dampener.
For stability, the Avidyne runs Windows NT which, we can tell you by direct experience, is far less susceptible to the kinds of crashes and lock-ups that Win 3.1/95 users consider normal. By using a commercially available operating system, Avidyne makes the job of creating third-party plug-ins easier, which should yield a larger library of applications. This may be critical to market success.
Unlike other manufacturers, Avidyne doesnt offer the option of using the MFC as a general-purpose computer; dont plan on using your favorite spreadsheet on this system. The software is all purpose built for this machine.
As a measure of the challenge it presented, the display is fully half the cost of the entire system. Its a backlit LCD designed to work at all light levels. But even the best LCD display is very inefficient. When a pixel of the display is open and set to pass light, it only passes 7 percent of the available light, absorbing the rest as heat. To make the display daylight visible requires bright backlight, meaning gobs of power and heat.
What Itll Do
The current system (Release 1) started shipping last October and has only VFR and IFR charting applications, with moving map. The VFR charts include WACs, sectionals and TCA charts. The charts arent electronically produced from geographical data but are instead scanned from the paper originals. This introduces some interesting effects. For example, at certain resolutions, the text looks out of proportion to the screen size. The IFR charts (currently NOAA products) suffer from a more serious problem: At some enlargements, the text reaches the limit of the scanning resolution and becomes hard to read.
The system itself has 32 MB of memory and 1.4 GB of disk space; not enough to hold all the data. So Avidyne has provided two ways of accessing data: You can remove the system and run it at home on a separate power supply, which allows you to attach it to peripheral devices (such as an external CD or diskette drive) and allows practice outside the airplane. Or, you can purchase a CD-ROM drive for the airplane and mount it under the MFC.
Release 2 is planned for the end of March and will provide charts plus a lightning detector display and a navigator function. The lightning detector is designed for the new BF Goodrich EX-500; a sensor only, no display. The Avidyne can accept input from a variety of GPS units as well.
Release 3, planned for July, will add a weather radar interface. This software will be an interesting use of the computer, since Avidyne claims the radar interface will provide better signal processing for some old radar unit than the original display did.
Note that were listing which release supports which functions. The applications arent included in the base price. Heres how the prices break down under the current price list:
The base unit itself is $7500, the CD-ROM is an additional $1000, the charts application costs $1000, the lightning detector will add another $2000 for the software plus $5995 for the BFGoodrich hardware. The navigation and weather radar interfaces will costs $3000 each.
Bottom line: Buy all of the available applications and youll be out $20,500 before installation. Obviously, thats a princely sum. But theres good news on the horizon. Avidyne engineers say prototype color-reflective displays being developed run cooler and are much cheaper. Since the display accounts for half the cost of the box, these displays would lower the price significantly. Stay tuned; maybe not next week, or next month but within a year or three prices may drop.
Archangel Avionics has been developing cockpit computers since 1992 and first displayed at Oshkosh in 1995. They have two products, an FMS that performs many of the same functions as Avidynes MFC and an EFIS, which is designed to replace mechanical flight and engine instruments with electronic versions on a single display.
Archangel, like Avidyne, believes that a certified unit is the way to go, because it can be installed in a production aircraft without reclassifying it as Experimental. Theyve been supplying non-certified units to the homebuilt industry for more than a year but have been actively pursuing certification, with new equipment being designed from scratch.
In the case of the FMS, this means an operating system change from Windows to a proprietary system. One unfortunate result of this is that the certified unit will initially offer fewer features than the non-certified unit. (The price of progress when the FAA gets involved.)
Both units use a very large 8.25 X 11.25 inch display and have a relatively shallow depth (4.5 inches), although any application other than navigation requires additional remote boxes. The FMS and EFIS are independent systems (separate CPUs) and can be used separately or together, feeding one display.
The Archangel displays have one other notable characteristic-theyre touch-screens. You make selections by touching the screen instead of using a mouse or joystick, just like those cash register systems in some restaurants and bars.
Archangel expects the FMS to be certified by the end of February, 1998. Curiously, the certification avenue theyre pursuing will approve the FMS only as a cabin information system. This effectively prevents it from being the primary navigation information, thus it cant replace required engines and flight instruments and nav gear in the airplane just yet.
The current (non-certified) version offers many of the features that other companies are only talking about thus far, including both VFR and IFR charts (Jeppesen NavData), approach plates, Stormscope interface, preflight planning and the capability to display downloaded weather data. The initial certified version will only offer IFR charts, a lightning overlay and limited pre-flight planning capability. Archangels FMS will cost $13,000 and the EFIS is $20,000. As with Avidyne, the lightning detector must be purchased separately, along with other interfaces as they become available.
The large size of the Archangel display is both good and bad news, in our view. The good news is that the display is easy to read and has room for plenty of stuff. The bad news is that installation could be difficult and perhaps impossible in many panels, such as a Mooney or other small airframe.
Technon Group has taken a different approach to the cockpit computer problem. Instead of spending money on certification (Archangel estimates the cost of certification to be in excess of $100,000), they offer a portable system that doesnt require certification or even so much as a logbook entry.
Technons unit-which it calls the Flight Pad-can also be used as a general-purpose (Windows 95) computer with the addition of a keyboard and a mouse. Any software that runs on Windows 95 will run on this machine and it can run on either ships power or batteries.
So where do you put it? Technon sells a flight case with room for the base unit. The display (7.9 X 13.4 X .75 inches) is billed as a kneeboard display panel. Like the Archangel, its a touch screen, but requires a stylus with a tether cable.
The stylus is a potential annoyance (think about trying to find it quickly in turbulence), but it does allow you take notes. Technon includes an electronic paper utility that lets you write directly on the display and store it for later use.
While Technon lists many other applications, theyre all flight-planning, moving map or procedural (weight-and-balance, checklists) applications. None of the higher-tech goodies such as lightning detection or engine data monitoring are available because of the portable nature of the machine. The Technon is cheaper than Avidyne but not cheap. The unit itself is $4395, plus $285 for a PCMCIA interface, $165 for the flight case ($30 additional for leather). It could, of course, double as a standard laptop, but not a very convenient one.
Like Technon, JPI has developed its own version of a portable computer, the NAV-2000. The computer itself (a 133 mhz Pentium) lives in a remote box mounted somewhere in the cabin or simply carried along as a portable. The box has a single floppy drive, a CD-ROM option plus a small keyboard.
The 7.5 X 6 X 1inch portable screen unit is connected to an umbilical and has an onboard trackball mouse, although it will eventually have touchscreen capability. Weve seen the display and agree with JPIs claim that its bright and crisp and also sunlight readable.
Like the Technon, the NAV-2000 is intended as a moving map device, but with general PC capability as well. It runs off-the-shelf Windows programs so anything you can run on your desktop, you can run on the NAV-2000.
It will accept position information from any of the popular GPS units through a serial port but the basic price includes a Garmin 35 GPS sensor. JPI reports that its working on ways to accept input from JPIs panel-mounted engine monitors and from other remote sensors.
At present, the NAV-2000 requires no TSO or STC but JPI says it may eventually pursue a TSO, assuming one can be found or devised to apply to this kind of equipment. At $2995, the NAV-2000 is the cheapest of the lot and for many buyers, may come close to a mad money expenditure unencumbered by worries about future value.
Buy Now or Wait?
This is complex subject. As far as non-certified portables go, theyre unlikely to have the capabilities that certified units eventually will. So fancy stuff such as glass gyros, engine monitoring, nav output or storm detection may never apply to those devices to the extent that theyll replace the approved equipment.
If you find a non-certified unit that does what you want right now for a price youre willing to pay, buy it. Just dont count on promised future capabilities to justify the investment.
Whether certification is really an issue worth worrying about is unclear at this point. Avidynes STC approval process, for instance, merely allows the equipment to be installed legally without interfering with basic aircraft operation. For now, the display doesnt officially displace legally required instrumentation. Ditto the Archangel.
None of the certified units are being sold on what they can do today. Few aircraft owners would pay $15,000 (plus installation) to view sectionals on a screen. If you add lightning data, you get significantly more capability but the price soars another $6000; the cost of new IFR GPS.
What these devices are selling is the future. A system that displays your position overlayed on an en route or approach chart, further overlayed with lightning data and Internet weather data, with engine data as an option, has definite appeal and is the way of the future.
But that system doesnt exist yet in any light aircraft configuration. Were encouraged by what weve seen so far but the promise of these flight computers is still around the corner.
If you have the computer platform already installed, you might just be the first on your block to fly behind such a fully certified dream system. Out go the steam gauges, in comes the EFIS. But there are still far too many unknowns to predict if any of the systems mentioned here will evolve into the ultimate glass cockpit computer for small aircraft GA. And until the current units operate for a few years, we have only the engineers opinions that the electronics are robust enough to handle the vibration, heat and cold of the real world.
Its entirely possible-indeed, likely-that well see major changes in these units before a design emerges that meets the stability and price requirements of the average aircraft owner. Even then, the software may have years to go.
With Windows NT or proprietary operating systems, PCs are very stable. But is very stable good enough when youre in the soup with the family in the back? And how stable is very stable anyway? Is it as reliable as a standalone Stormscope, for example?
And how about future support? These systems are be pioneered by small companies. If the company behind your system goes under, where will the new customized applications come from and who will update your current applications?
If enough units are out in the field, there might be a dedicated programmer out there who will pick up the slack. But we see the support issue as unclear at best, risky at worst.
If you have a spare $20,000 to $30,000 kicking around and dont mind being on the crumbling leading edge of technology, take a look at any of these systems. They really are remarkable achievements.
But we think the average aircraft owner is better off waiting for the projected improvements, cheaper displays, a proven disk suspension system, a proven operating system and a lower price. These developments will truly herald the navigation system of the future.
Its coming; its just not here yet.
-by Jonathan Spencer
Jonathan Spencer is a freelance writer and Cardinal owner based at Bedford, Massachusetts.