The Brave New GPS World is A-Coming


by Alfred Scott

This article was published in the December 1991 Falco Builders Letter.

Whiners and complainers about the lack of progress in aviation simply have not been watching what's been going on with electronics and avionics. Oh sure, there are other areas where there has been progress, and like all technological advances, they come one small step at a time: The new generation of lightweight starters. Satellite weather maps. Teflon engine hoses. Teflon-lined engine controls. A better design for a fuel selector valve. Composites for various components.

But the most exciting changes have been in the world of electronics, and what we've seen to date is only a tiny taste of what's to come-and sooner than you might think. Today's crazy dream has a habit of becoming tomorrow's reality. And no sooner than you have enunciated a bizarre scheme do you find out it's already been done.

Homebuilders are rightly proud of pointing at the Wright brothers and the Voyager as major milestones in aviation which belong in their camp. Give credit also to the free spirits of aviation for bringing loran to aviation. Free to put anything in their panels, certificated or not, homebuilder buying habits have become the bellweather indicator of the market-indeed most industry observers pay more attention to what's selling at Sun 'n Fun than at the NBAA.

The pieces of the puzzle are coming together rapidly. First there were the simplest of devices, encoding altimeters that brought the modern miracle of silicon chips sensing light shining through holes in a revolving disk and then another chip that could count the blips and turn that into useful information. The microprocessor and other forms of chips started making their way into our panels.

Remember the excitement associated with RNAV when it first came out? Have you ever thought about how primitive RNAV really is? The calculations can be easily done on any hand calculator, and I could program an entire RNAV in a single page of Pascal. Yet these things sold for $6,000.00, and we marveled at the ability to 'move a vor' and fly to any point we choose.

Then came loran, which brought reasonably accurate, go-anywhere navigation. You could taxi along a grass strip and the dang thing would tell you how fast you were going, and how far it was to your destination. The earliest units had only a few user-waypoints, and I remember when a friend who flew Spitfires for the RAF regaled me with stories of this amazing modern invention. He described what it was like to scud-run down the Long Island shore under a 200-foot overcast in his CAP-10 and know precisely where he was and how to get to the airport. That was six years ago.

Today lorans come in every shape and size, and the variety is astonishing. Once you have the ability to know where you are, then you have to deal with the realities of translating airports, VORs, intersections, TCAs, TRSAs, MOAs, etc. into lat-long data and back. It didn't take long before these things had databases with all that info in the loran so that you could punch a button to get directions to the nearest airport, the frequencies at the airport, and the telephone numbers of the local motels and restaurants. Now it's a question of the quality of the database, what's included and ease of use.

I've happily bombed right through the Philadelphia TCA on several occasions, only to discover it after I casually glanced at my map. But if Jonas Dovydenas were to do that, the Warn button on his Northstar would flash, and all you have to do is punch the blinking button to be told that you're in the TCA, and it gives you the frequency to call the controller.

These things are so cheap that I have several friends who are already on their second lorans. They simply trashed the first one and replaced it. And these avionics devices are free of the product liability claims that push the prices of other products through the roof-I've sat in the hot tub at the Oshkosh hotel and listened to the overweight and prosperous salesmen from II Morrow extol the virtues of volatile memory. Unless you go to your death -- thus converting yourself to something the kids around here call 'street pizza' -- screaming the lat-long readout of your loran on the radio, how's anyone to know if your navigation system was at fault?

Now comes GPS, a satellite-based global positioning system that's going to displace loran, ADF, VOR's and probably even ILS in time. I have on my desk the spec sheets for the Sony GPS (list price of $1,395.00 -- street price will obviously be much lower) a palm-size portable that weighs a little more than a pound and which will tell you your location to about 100 feet and your speed to an accuracy of 0.35 mph. I find it astonishing that you can stick one of these babies in your airplane and in the event of total electrical failure, you can have a precision navigation system that runs for eight hours on four AA batteries.

You don't have to be very smart to figure out what's coming. You've got a very accurate method of determining your location. You've got all the information from maps and approach plates in a database, and this information can be displayed in a variety of ways. You've got accurate fuel flow data from a fuel totalizer. Throw in an autopilot and the power of an inexpensive personal computer and you have all the makings of an astonishing navigation system.

You have today all of the pieces you need to have your own custom instrument approach to your grass strip out in the boondocks. Hook up a portable PC to the plane, and you could even let the PC fly the plane down to your minimums-hell, let it land the thing in an emergency, it would certainly do better than you would in that situation.

My latest issue of Flying has an advertisement for a little handheld 'calculator' that has a full aviation database for only $140.00 plus $40.00 for each card for the three other sections of the country that you might want. Later in the same issue, there's a review of the Garmin GPS, which at $3,600 list has a full Jeppesen database. Also in the same issue is a notice that the FAA says that GPS receivers may not be used as a sole means for IFR navigation nor can they be linked to any other avionics-are FAA employees the same species as the rest of us?

II Morrow has just come out with a GPS version of their Fly-Buddy loran (street price $2,100) , and Dick Wagner is working with the orientals to bring out a low-cost GPS with a full database. Like the Wag-Aero nav-com, it will have a battery backup in case of power failure. I can well imagine that a standard feature of future airplanes will be a neat little row of AA batteries that back up all of your equipment in the case of power failures. In the event of a power failure, part of your survival would be switching batteries to keep things running -- lemme see here, our GPS is running low, so let's steal the batteries from the clock-timer, and let's switch the flashlight batteries with the nav-com batteries.

When my Falco was flown over from Ireland in the early eighties, the pilot used a monster loran that he carted with him. From Iceland to Canada was an eleven-hour leg, and over Greenland the thing didn't work at all. Today he would just need a Sony GPS which he could slip in his pocket. It would be lighter, cheaper, more accurate and would consume less power. And if that's not progress, I don't know what is.

Although the FAA will probably have to be dragged kicking and screaming into embracing GPS, there's no turning back. Fortunately, loran has served as a precursor to GPS and has put everyone in the right mindset. We now have an improved safety record in aviation, and it's impossible to prove, but I'll bet an important part of that is due to loran's ability to guide a pilot in bad weather and low on fuel to some little field out in the middle of nowhere.

I think the future belongs to GPS. The FAA could scrap the entire VOR and ADF system, give every pilot a Sony GPS, tell them to go fly, and I'll bet they'd get their money back in less than six months. It's a silly thing to suggest that the U.S. government give Japanese avionics to pilots for nothing, but the cost savings are probably there. The whole idea of terminal area radar starts to make no sense, rather than bouncing signals off airplanes, why not just let the airplane tell the controller's computer where it is? The function of the transponder would be replaced by a radio which would simply 'talk data' back and forth with ground, whether in radar contact or not.

Instructions to fly various headings could be done electronically and could be displayed on your moving map display as a flashing arrow. Same kind of thing is easily do-able for the location of other airplanes. Faxed weather maps. Feelthy pictures. The FAA is proposing that we now have to install Mode-S transponders on new planes, and these have the ability to transmit slightly more data to the ground, including (gasp!) your N-number. What we really need, though, is some radical thinking and a device which will serve as a radio-based RS-232 serial port for the airplane-one that can accommodate the inevitable changes in software on each end.