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Glass cockpits and advanced aircraft in G/A


There’s been a lot of talk about glass cockpits, automation, and pilot proficiency lately; several high visibility crashes, and a 2010 NTSB report indicating that single-engine glass aircraft had no better safety record than airplanes that were conventionally instrumented. Ouch!

That’s a statistic that is sure to turn some heads, and it comes from a good set of data (over 266 total accidents between 2002 and 2008 for conventional and glass aircraft). Adding insult to injury, there was a higher fatality rate for the glass accident aircraft category than for their “steam gauge” brothers and sisters.

While there are lots of nitpickers complaining about this report comparing apples and oranges (e.g. the average mission for glass aircraft might be different than for non-glass, etc.) the data doesn’t lie, and so we are left trying to figure out what’s going on!

The introduction of glass into the general aviation fleet was expected to improve the overall accident rate, and that has not happened; I’ve found no way to argue with that point. The good news is, people have been working that problem since the late 1980s, so we have some insights to the problem we can learn from.

Glass and advanced automation did not start in general aviation, but rather sprouted from within the airline transport industry. From early on, a perceived loss of flying skills was the main concern of pilots. While perceptions do not necessarily influence performance, the fear was that with glass cockpits came advanced automation; and with advanced automation came complacency.

This is somewhat of an intuitive perception, but no one could really prove that it was true. After all, anecdotal stories from a few respectable pilots do not make a seemingly important issue an issue for more than that particular handful of pilots! However, one could hardly dismiss the feedback coming from experienced flight deck crews about their experience with glass and automation.

For example, one researcher cited comments from crew members regarding younger pilots on the flight deck. Being more adept at computer use, the younger pilots were more likely to rely on the automation far beyond the point where they should forget it and “manually fly the airplane.” An important point to be sure, as it recognizes that the current generation of pilots better grasps the fundamentals of computer use.

Unfortunately, the lack of overall experience provides questionable ability in case of automation failure. An old article in Aviation Week and Space Technology quoted one Boeing 757 pilot who talked about some pilots leaving the automated aircraft and going back to non-automated aircraft (for a variety of reasons, and not necessarily by their own choosing). He further stated, “I was somewhat concerned with the I-can’t-fly-anymorebut- I-can-type-80-words aminute syndrome;” a clear acknowledgement that pilots were worrying about skill degradation as a result of letting the automation manage the flight by itself all the time.

So that’s a bit of the history, and clearly, there is a precedent for the issue of pilots trusting automation more than their own airmanship. But another issue also comes to light, especially when considering the work that NASA’s Stephen Casner has done. A two-fold issue, one of both complacency and risk taking, comes into view when considering pilot’s perceptions and actions when flying automated glass aircraft.

There’s a suggestion that pilots may become too complacent, perhaps thinking their automation will take up the slack if their own skills are a little lacking. There’s also speculation that the automation entices pilots into more risky behavior. To the point, Casner, in a 2008 report states, “that pilot’s beliefs and attitudes about advanced cockpit systems can sometimes be powerful determinants of pilot behavior and performance in the cockpit.”

This conclusion was based on a previous study were he queried pilots who regularly used GPS and moving map displays about their navigational awareness and to pilots who navigated using a sectional chart and good-ole pilotage in a conventional cockpit.

Not so remarkably, the GPS pilots believed their awareness to be superior in the presence of a GPS and moving map, and they appeared to be less active in the managing the navigational process during flight. When they had to demonstrate the task of navigational awareness, they performed worse than the pilots who did not regularly use the automation to help navigate. Clearly, our confidence about our own proficiency can be influenced in the presence of the advanced gadgetry.

In terms of risk-taking, the advanced glass cockpit may lull a pilot into thinking that they are capable of handling more during flight than in a conventionally equipped aircraft. In fact, that may be true under certain circumstances, but it does not eliminate the need for the pilot to be capable of stepping in to take over the flight manually when the automation fails. And as with all things in life, if you don’t practice those skills from time to time, you lose them!

But is this all there is to say about the problem of manual reversion when the automation fails? Perhaps not. Perhaps another aspect to consider is the “startle effect.”

When using automation for long periods of time, the pilot’s level of involvement in situation awareness may already be hindered to the point where significant effort is required to jump back into the flight. Enter the automation failure! At this point in time, one would think that you just grab the control column and smoothly take over as if nothing serious has happened.

It turns out that people just don’t respond this way. More times the not, the startle effect takes over immediately upon equipment failure (since they are usually unexpected) and, psychologically speaking, they revert to more basic responses of what was learned by rote or first motor memory of action.

This basic response may not be right, and the resulting error reduces the time to make a corrective action. Even if the pilot is not startled, action is at many times slowed by denial (the automation never failed before!) or a futile attempt to “reboot” the equipment.

While my experience with glass is limited, I can say with certainty that I’ve never successfully resurrected automation after a failure during flight. And where do you suppose the automation will fail with the most consequences?

If you said during the terminal arrival phase, then you and Murphy agree. Murphy’s Law dictates that the automation will fail when you have the least time to correct the problem, as well as when the most effort is required to manually fly from that point onward.

So what can we learn from all this?

1) Despite the NTSB’s report, there is no good evidence that advanced glass single-engine airplanes are actually more dangerous than conventionally equipped single-engine airplanes. In fact, there is more evidence to suggest that pilots use these aircraft in ways that are different than for similar performing conventional airplanes.

And, unfortunately, they may fail to understand that having an advanced cockpit does not mean they or the aircraft are capable of anything more than they would be in a conventionally equipped aircraft.

In examples above I talked about skill perception and risk-taking. There is evidence that advanced automation changes the way pilots perceive their abilities and so there is a real concern that they may take on riskier flight behaviors.

2) While there is no good evidence that G.A. pilots fail to understand how to use their advanced glass, remember that there is a precedent for pilots not understanding what’s happening when something goes wrong or the automation fails. This problem is tied to the opaqueness of how systems operate in a glass cockpit.

As automation increases and the pilot is relieved from traditional monitoring tasks, the ability to step in and take over with a high level of situational awareness may diminish. The solution to this problem is not straightforward. However, regular proficiency training is one step in the right direction. Another step is to take formal training on any advanced equipment or “glass” that might be installed in your aircraft.

3) We are fast approaching the time when all general aviation aircraft will be coming off the factory assembly line with glass cockpits and GPS as the primary navigation system. The glass and automation enhancements were designed to reduce workload, improve efficiency and provide for a safer flight environment, but the accident rate studies have failed to make a strong case for its use over a conventionally equipped aircraft.

I firmly believe this finding is an artifact of the way pilots are flying these aircraft and the level of experience they have prior to trying to extend their flight mission beyond what they would accept in a conventional steam gauge aircraft.

I also get the sense that some pilots leap to accept advanced aircraft prior to really learning how to fly them. Of course I see that in the current generation; computerized and automated gadgetry can’t come out fast enough to suit most people.

This doesn’t mean we avoid the glass and advanced systems; on the contrary, we should embrace it and learn it well. But foremost, we all need to keep in mind that sooner or later the glass goes black, the automation fails, the GPS loses RAIM, etc. When that happens, all that’s left in our bag of tricks is our piloting skills, and if those are rusty then we’ve got a problem!

With that in mind, turn off the automation, simulate failures, and do it the “hard” way often enough to keep proficient. And if you’re new to advanced aircraft flying, consider whether you’d make the flight in a conventionally equipped aircraft first. If the answer is “no”, then you may not be ready to do it in the advanced aircraft!

This month’s Pilot’s Primer is written by Donald Anders Talleur, an Assistant Chief Flight Instructor and Researcher at the University of Illinois, Institute of Aviation. He has been flying since 1984 and in addition to flight instructing since 1990, has worked on numerous research contracts for the FAA, Air Force, Navy, NASA, and Army. He has authored or coauthored over 200 aviation related papers and articles and has an M.S. degree in Engineering Psychology, specializing in Aviation Human Factors.