The introduction of Garmin’s new GTN touch-screen navigators, the GTN 650 and the large GTN 750, is remarkable in itself, but the fact that we’ve almost come to expect such works of seeming magic in our cockpits made me think back to the original precursor of the GTN products, the GNS 430, which I met for the first time a dozen years ago.
It’s hard to overestimate the impact of what we’ve all come to refer to simply as “the 430. It was central to Garmin’s success in aviation and to the widespread adoption of graphical, software-based navigation tools to our personal flying. I know it’s hard to remember that not too many years ago, nearly every one of us (excepting the folks who flew 777s and Airbus A300s) flew airplanes outfitted with what we now somewhat pejoratively refer to as “steam gauges.” These instruments required us to take multiple instrument indications and develop in our minds some kind of picture of what that meant to our flight situation. A much more direct representation of our flight situation was sorely needed.
Not that engineers weren’t trying to do just that. They were. It’s just that these instruments were developed over a period of many decades, and avionics manufacturers actually made some extremely ingenious improvements to them over the years. Such features as “flip-flop” frequency selection, textual displays, the horizontal situational indicator (HSI), and electric standby attitude instruments were all successful attempts to push the limits of the existing technology so it could provide safety or ease-of-use capabilities — like somewhat improved situational awareness, crude forms of graphical interface, or enhanced redundancy that it otherwise would not be able to.
