Pilot Pet Peeve #1: The Instrument Panel

October 28, 2009

5 Min Read
Pilot Pet Peeve #1: The Instrument Panel

Luddite: N. The Luddites were a social movement of British textile artisans in the early nineteenth century who protested–often by destroying mechanized looms–against the changes produced by the Industrial Revolution which they felt were changing their way of life. (Source: Wikipedia)

My friends say I’m a known curmudgeon and a suspected Luddite. On the first charge, I plead guilty and throw myself on the mercy of the court. On the second, it’s difficult to refute that notion when it turns out I only recently broke down and bought a Black Berry.

So, with that second charge in mind, see what you think about this:

Here’s the instrument panel in my airplane, a 1980 Piper Seneca:


With the exception of the GPS Moving Map and the Thunderstorm Avoidance device directly below it, this instrument panel is a study in archaic technology.

The artificial horizon and directional gyro instruments in front of the pilot and co-pilot are powered by pressure differential–in this case about 5psi–which means they’re spinning at several thousand RPM on bearings that eventually are going to wear out. It also means that the air pumps supplying the pressure differential are potential failure points.

But it’s the avionics stack in the middle that makes friends think I’m a Luddite. Notice the toggle switches on the top unit, the widely spaced knobs on the next unit down and the large knobs on the communication and navigation radios in the middle and at the bottom. Hold those perceptions for a minute.

Check out the panel used in a particular corporate turboprop; an airplane I’ve flown many times and really like:


The three flat panel displays are awesome to look at. They furnish more information, better organized and more easily assimilated than I could ever experience in my Seneca with its steam gauges. Those smaller units beneath the center display are the communication and navigation control units. They’re very versatile and neat to look at too.

But look more closely at the displays and the comm/nav units. See all those tiny little buttons and equally small knobs–knobs and buttons that have stuff right next to them unlike the wide spaced knobs in the Seneca?

Now, have a look at what happens to all these knobs and switches when the bumps start:


Imagine you’re hurtling through the air at say 3 miles a minute, in cloud, with a load of passengers who are convinced they’re about to die. You don’t have a flight attendant to soothe their nerves. In many cases, you don’t have a co-pilot either. If you’re lucky, the autopilot is working but in really heavy turbulence, you need to hand fly the airplane or at least decouple the altitude hold in which case you are alternately soaring upwards at a thousand feet per minute followed by equally fast descents.

Imagine yourself flailing away, trying to make a direct hit on a soft key on one of those displays, after you’ve finally been able to grasp a mode or function select knob and change the key’s function to the one needed at the moment.

Air Traffic Control will ALWAYS give you a frequency change in the middle of all this commotion so you also get to deal with the ultra-sleek but devilishly difficult to operate comm/nav controls just at the moment an updraft hits you and a side gust pushes you towards Atlanta at the same time.

So, my designer friends, since the people who develop the human interfaces for these devices don’t seem to mind causing those who engage in turbulent instrument flight major headaches, maybe some of you who are not in that industry can offer them some assistance.

Here’s my suggestion, just to get the discussion going:

How about some relatively large rocker switches, a relative large knob, a data bus, a control display (sufficiently large that the text can be seen when your eyeballs are bulging out due to the potholes in the sky) and a nice sized trackball? And how about you add some nifty “U” shaped thingies - that you can hook your pinky finger around - in close proximity to this grouping of controls?

The flat panel displays are in front of you–just like now–but when you want to change a function, you address the device you want to talk to with the “relatively large knob”, roll the “nice sized track ball” to the function you want to change and press one of the “relatively large rocker switches”. Now that you’ve arrived in a new neighborhood, you roll the “nice sized trackball” to the parameter you want and either select it directly or use the trackball in concert with the rocker switches go somewhere else where you repeat the performance to adjust frequencies, select airways, control the auto-pilot or whatever. You get the idea.

So that you have redundancy, you put one of these control devices on each side of the airplane but within reach of either pilot. Next to the throttle quadrant or between the seats comes to mind. And in case its dedicated display dies, you build in fall back capability on the center flat panel display.

Something like this also addresses another pet peeve: Why does each flat panel display need its own dedicated controls? Isn’t that why we have data buses? And given that even airliners have bouts with turbulence, how come the state of the art glass cockpits are designed in a way that’s so difficult to interact with when there are cobblestones in the path?

So what do you think? Any ideas on how to solve this really annoying problem that pilots deal with every day?

John Loughmiller is an Electrical Engineer, Commercial Pilot, Flight Instructor and a Lead Safety Team Representative for the FAA. He can be reached at [email protected].

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