The GPS learning curve

May 1, 1996

An ancient curse in a Chinese fortune cookie says, "May you live in interesting times." This is supposed to inflict the recipient with doubt and uncertainty. As aviation makes the change from ground-based navigation — VORs, NDBs, and ILSs — to satellite sources, these truly are interesting times. Do you have any doubt or uncertainty?

In the GPS environment there is no longer the simplicity of merely tuning a frequency and setting an omni bearing selector. Now the equipment must be "programmed" because we are dealing with powerful microprocessors. GPS receivers are capable of doing more than some of us ever imagined — or, in some cases, even wanted. But that's progress.

The burden of flying with GPS is to understand the processing power in your panel-mount unit or handheld. It is capable of taking you anywhere on the globe and at virtually any altitude. It can route you straight through a hot restricted area, into communication airspace without a clearance, or directly into the side of a mountain while you think you're on approach. It's something like Adam's biblical apple — the knowledge of good and evil.

I have taken a bite of the GPS apple and come away with great respect for the device's capabilities and certainty. It is certain that some serious training is needed on these units in order to operate them safely in the IFR environment. This is not intended to scare you away; IFR GPS can be mastered by mere mortals, but some time is required.

If you fly VFR point to point, there is the luxury of fiddling with the box until something resembling the destination comes up. But even this does not come without a downside. Keeping the aircraft right side up has always been something of a priority with me. An autopilot, or at least a wing leveler, can be awfully handy if you're in a hurry to launch and don't get the gizmo programmed before becoming airborne.

A plus for GPS is that programming one destination definitely takes less time than tuning multiple VOR stations en route. However, if a multi-waypoint trip is anticipated, there is a distraction factor.

The new electronics are more mesmerizing than ever. Pilots tend to be gadget freaks, and many enjoy the challenge of loading the navigation unit — sometimes to the detriment of other very important tasks, such as looking for other aircraft or maintaining altitude and heading. Since traffic tends to cluster near airports, we should voluntarily establish a "no-fiddle" zone within 10 miles of departure or destination in order to ensure that a good lookout is kept.

The human interface, as the psychologists like to call it, is rapidly changing in the cockpit. Radios are no longer merely tuned — systems are programmed. Gone is the simplicity of four selectable digits on the navcom. Now there are five programmable digit-and-letter combinations that permit literally tens of thousands of combinations.

Airline pilots have already experienced difficulty with programming flight management systems, although the airline boxes are quite a bit more complex than a typical GPS. Airline aircraft also move faster than ours, but there is another set of eyes and hands to help.

Before you despair, however, remember that these are first-generation IFR units and the technology will certainly improve. The marketplace has a way of making that happen, and usually pretty quickly.

Some people resist technology because it means change. It requires learning, thinking, and practice. But as one early GPS convert pointed out, we have invested a lot of time learning VOR, NDB, and ILS.

Instrument training devotes at least 15 hours of concerted practice on making peace with the electronics and learning to interpret the arcane displays of 40 or more years ago. GPS is a more versatile tool that will provide fabulous benefits — but, as in the case of the apple, there is a price to be paid. We have to learn how to use it.

Another comforting thought is that you don't have to go solo early in the process. The old reliables, VOR and NDB, are there to turn to during the learning curve. Any time you start to lose the picture, just switch back to the old system and resolve to practice your GPS skills some more.

Sometimes, however, GPS can bail us out on the old equipment. One experienced pilot confessed to having misset the horizontal situation indicator for an ILS approach so that it was providing improper guidance. The GPS moving map display immediately showed the error, so the problem was corrected.

The AOPA Air Safety Foundation is conducting GPS seminars for general pilot audiences. The program "GPS — Magic Box or Pandora's Box?" has been well received by thousands of pilots. It explains what GPS does, how it can be used, and that it presents some potential pitfalls. The seminar will be held in dozens of cities this year. Watch your mailbox for information. A course later this summer will teach pilots and CFIs about specific units. ASF will also conduct GPS training in Flight Instructor Recertification Clinics.

The transition to GPS will be as challenging as learning VOR — but with a bigger payoff. May you too live in interesting times.

For a copy of ASF's free safety advisory pamphlet on GPS, send a self-addressed stamped envelope to: AOPA Air Safety Foundation, 421 Aviation Way, Frederick, Maryland 21701, Attn: GPS Safety Advisor.


See also the index of "Safety Pilot" articles, organized by subject. Bruce Landsberg is executive director of the AOPA Air Safety Foundation.