Technology plays a major role in alerting flight crews to potential aircraft problems, guiding them through stormy weather and protecting them from unruly or dangerous passengers. The recent tragedy of Germanwings Flight 9525, however, makes it clear that, no matter how simple or sophisticated a technology, the human factor is pivotal in determining the likelihood that a flight will end with a safe landing.
Stuff does happen, but flying is still an extraordinarily safe experience. By some measures 2014 was the safest year on record for modern air travel, thanks to advances in guidance, navigation and other crucial systems. Last year global jet accident rate was the lowest in history—the equivalent of one accident for every 4.4 million flights, according to the International Air Transport Association (IATA), which represents 250 airlines comprising 84 percent of global air traffic. This was an improvement over 2013, when there was an average of one accident every 2.4 million flights.
Yet 2014 was also marked by several high-profile air disasters, which demonstrated that, no matter how safe, it is still possible to crash an airplane—and the causes of the accident are likely to result from an unpredictable interaction between the pilot and the aircraft’s technological complexities. In March Malaysia Airlines Flight 370 and all 239 people onboard vanished mysteriously en route to Beijing, highlighting flaws in the ability to track aircraft over remote areas. Another 162 lives were lost in December when AirAsia Flight 8501 went down in the Java Sea. That wreckage was found, and investigators have been examining the role that a faulty onboard flight augmentation computer may have played in that disaster.
In the case of Flight 9525 a reinforced door installed to defend against 9/11-like attacks on cockpit crews prevented the Germanwings pilot from stopping what is believed to be an intentional crash of the Airbus A320. With the pilot seemingly powerless to retake control of his aircraft from the co-pilot—who had locked himself in the cockpit and prevented anyone from entering—might there have been some other technological advance that would have allowed controllers on the ground to override onboard systems and guide the plane to safety? The initial response from several airlines has been low-tech, issuing new policies that require at least two crew members in the cockpit at all times.
But other observers wondered whether another solution might be in the offing. As military drones have demonstrated in recent years, the ability to remotely control large aircraft on long flights does exist. Still, the mere presence of advanced technology does not guarantee a safe flight, particularly when the people handling that technology cannot be trusted to use it properly, says Bill Waldock, professor of safety science and director of Embry–Riddle Aeronautical University’s Robertson Aircraft Accident Investigation Laboratory. Scientific American recently spoke with Waldock about the many factors that go into getting passengers and crew safely from point A to point B, and the need to balance increased aircraft automation with good piloting skills and instincts.
[An edited transcript of the interview follows.]
Much has already been written about the potential causes and fallout from the Germanwings crash. What stands out as the single most important issue related to the Germanwings tragedy?
One area that media outlets seem reluctant to pursue is the trust issue. Airline pilots have exactly the same moral and ethical responsibility as the captain and crew on a passenger ship—and that’s the safety of their passengers. When you climb into that aluminum tube, you’re putting your life in those pilots’ care. And that trust in this case has been completely violated.
The number of airline crashes dropped in 2014 whereas the number of deaths related to airline crashes spiked. Was this an anomaly or a sign of some greater problem in air travel?
The general trend is that safety has improved worldwide but it’s still not really where it could be. We still have problems with pilots and automation. The absolute priority anytime you’re flying an airplane is to fly the airplane. If you take a look at the transcript from Air France Flight 447, it’s absolutely horrifying that they literally had three and a half minutes to stabilize that airplane and no one in the cockpit realized that the stall warning was going off, even though it went off 76 times. You could hear it in the background on the [flight recorder]. The whole ride down the co-pilot had the left-side stick all the way aft. He actually was controlling the aircraft physically but he was keeping it in a nose-high deep stall, and nobody recognized it. To me that’s a failure of airmanship. We’ve seen more of that problem start to develop with the introduction of more automated aircraft.
Why would increased automation create more problems?
You trust the automation. When it’s working okay, everything is fine. When something fails, a lot of times the failure itself may be something subtle and the crew starts focusing on what the problem is and forgets to fly the airplane. That’s been true in several accidents. Aviation psychology folks call that “automation complacency,” and it makes us slow to react to certain situations. Other than Air France 447, another example of this was the TAM Airlines Flight JJ3054 accident in São Paolo, Brazil, in 2007—the worst air accident in South American history. They were landing at night in the rain and the airport where they were landing has a relatively short runway at [1,920 kilometers]. They were flying an autopilot approach, so the autopilot’s doing everything. The only thing the pilots have to do is, at touchdown, pull the thrust levers to the rear position so the thrust reversers activate. When you move the thrust lever on this aircraft [an Airbus A320] you’re not really doing anything other than telling the computer, “I want this thrust setting.” So far, so good.
When they did that they pulled only the left lever aft—they left the right lever at full forward. On this particular aircraft the right thrust reverser had been deactivated because it wasn’t functioning properly, and the pilots didn’t think they needed to pull the right lever aft [because when on autopilot the engine’s actual thrust power is not controlled by the throttle’s position but rather by the computer]. However, the aircraft’s system recognized it was out of configuration and shut down the autothrottle. The right engine went into takeoff power, while the left engine was in reverse. They didn’t even notice it until about half of the run. They were having increasing problems controlling the airplane, and they weren’t slowing down—they were actually accelerating. They went off the end of runway at 95 knots [about 175 kilometers per hour] and ended up stuck in a maintenance building. [All 187 people onboard were killed.] Because they were so used to not having to worry about those thrust levers, they just didn’t bother to pull the right one back, because they knew the thrust reverser wasn’t working.
To what extent could or should commercial air flight be automated?
The trend has been the more the automation, the more airlines put pressure on their pilots to use the automation because it’s more efficient, costs less and burns less fuel. What happens is your basic airmanship—stick-and-rudder skills that enable you to fly the aircraft by hand—begin to degrade unless you’re voluntarily practicing in a simulator or some other way. Consider the opposite extreme to Air France Flight 447, which was the Quantas Flight 32 emergency. That was an Airbus A380 that had its number-two engine explode in flight, damaging parts of the aircraft. The fault warning [computer] began loading pages related to repairs for the aircraft in response to the damage. That’s great if you’re looking at only one failure. But in this case all of a sudden the crew have 39 or 40 fault pages loading on their computer. How do you deal with that? You’re going to be overwhelmed if you try.
Luckily the captain had a second crew onboard, talked it over and decided to shut down the automated systems and fly by hand. They managed to get the plane down safely in Singapore. It’s a great example of airmanship, with another being pilot Chesley Sullenberger sticking US Airways Flight 1549 on the Hudson River [after its engines were disabled by a bird strike]. What those pilots had in common were that they were older pilots who learned to fly [before] all of this new technology was just being developed.
What is keeping remote control of commercial aircraft from being deployed?

There are [cybersecurity] vulnerabilities in certain areas even in the most sophisticated airplanes. A lot of that has to do with the very sophisticated entertainment systems that are being installed for the passengers that are not completely isolated from other systems in the airplane. That’s a weak point in a lot of airplanes, and a hacker could conceivably go through there. The biggest concern is just fear that the bad guys could take remote control of an aircraft. If that happens, we’ve got a real problem.
Cybersecurity aside, are there other technological barriers to a commercial airliner being flown remotely from the ground?
To do this you need to be able to track a flight from beginning to end. We’ve had the ability to track aircraft globally for quite a few years—really ever since GPS was developed. The reason we don’t have this tracking technology on commercial airliners is that there is an infrastructure cost to install all of the equipment. There are 7,000 to 10,000 aircraft in flight at any given time worldwide. That’s a lot of tracking via satellite, but the capability is there.
Emergency locator transmitters (ELTs) are another example of tracking technology that’s not being fully utilized by commercial airlines. The 406 MHz ELT broadcasts a signal to the SARSAT [Search and Rescue Satellite Aided Tracking] system, which covers most of the globe. It tells you not only the latitude and longitude of an aircraft but the altitude as well. Most large commercial airliners are not required to carry ELTs—it’s a cost issue. To me that’s a hole in the system. MH370 proved that commercial airliners can disappear.
Do you have any particular safety concerns regarding so-called “budget” airlines, like Germanwings and AirAsia?
It depends on the carrier and who they’re partnered with. Some of the feeder airlines do well. I would have no heartburn flying on them. It varies from airline to airline. Theoretically the size of the airplane and the type of operation is what should dictate minimum safety requirements—including aircraft equipment and pilot training. I was a little surprised that the Germanwings co-pilot had only a little more than 600 hours of flight time. In the U.S. most big airlines would want 1,500 hours, although it can be an issue of supply and demand. If there aren’t enough pilots, airlines have to decide whether they want to compromise on the experience requirements.
What are some of the more promising technologies for improving aircraft safety?
One of them we already talked about, and that’s the ability to globally track aircraft with GPS installed on the aircraft. That way we know where they are. Another technology that I would like to see to improve situations such as what we just saw with Germanwings is direct data streaming of flight recorder information to the ground. There has been a lot of resistance to that because it’s very expensive to do. Yet it took Air France two years and 20 million euros to find the two recorders from that flight. But if we hadn’t found them, we wouldn’t have known what happened during that flight. It turned out to be a very simple error of airmanship.
What makes that so expensive?
Both the bandwidth and the equipment are expensive because you’ve got to build the infrastructure. The infrastructure on the plane is essentially an interactive transponder system. That’s not necessarily all that expensive until you consider the large number of aircraft in the air at any given time. You’ve got to have the ability to download the info and know who it’s coming from. Then there’s the question of who’s going to pay for all of this technology. The airlines are already squawking about it, using the rationale that aircraft don’t crash enough.