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It’s no secret that the push for autonomous aircraft, at least in the civilian world, is fundamentally driven by economics.
In small planes like utility planes and helicopters, human pilots are disproportionately expensive: Not only do they require a paycheck, but they occupy a seat that might otherwise be occupied by a paying passenger or cargo. In the emerging urban air mobility sector, margins are expected to be so tight that many believe the industry can never scale profitably as long as human pilots remain in the equation.
Beyond the profit motive, however, proponents of autonomous aircraft routinely argue for safety to remove pilots from the cockpit, pointing to the high proportion of accidents resulting from pilot error. A typical example can be found in a white paper released last year by Wisk, the Boeing-backed electric vertical takeoff and landing developer.
Related: The daunting economics of taking an air taxi to work
Wisk cites a Boeing finding that around 80% of plane crashes today are due to human error, unlike the early days of flight, when 80% of crashes were due to mechanical failures. “By developing autonomous systems,” the document asserts, “Wisk will help eliminate these errors and create a fundamentally safe air taxi system for transporting people without an onboard operator.”
A parallel conversation has been taking place in the world of self-driving cars, or autonomous vehicles (AVs) – and recent developments in this space hold lessons for aviation.
Like aircraft manufacturers who have been content to blame pilots for 80% or more of accidents in their products, AV developers have done a lot claim oversimplified by the National Highway Traffic Safety Administration that 94% of serious car accidents are due to driver error. NHTSA used the statistic on its website to tout the potential of audio-visual vehicles “to take human error out of the crash equation,” saving lives and reducing injuries.
AV developers were quick to launch the claim. As Jennifer Homendy, chair of the National Transportation Safety Board, described in a recent maintenance“NHTSA has put [the stat] on his automated vehicles page, and all of a sudden, all the AV people were using it as a way to say, ‘well, see? It’s all just human error! Our car will just fix it.
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Last month, NHTSA deleted misleading number from his website, in part due to pressure from Homendy. A week later, the US Department of Transportation released its National Road Safety Strategywhich adopts the “safe system approach” as the guiding paradigm for addressing road safety.
According to the document, “it differs significantly from a conventional security approach in that it recognizes both human error and human vulnerability, and designs a redundant system to protect everyone.” Essentially, it recognizes that there are ways to achieve safety goals other than inventing superior robot drivers – such as redesigning road environments to promote safer speeds and make room for cyclists and pedestrians. pedestrians.
Despite its ingrained propensity to blame pilots, Part 121 commercial aviation is a triumph of safe systems design. Over the decades, flight operations in the United States and many other countries have evolved into incredibly safe and high-profile accidents like the 737 Max crashes.
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Today, many elements come together to maintain the industry’s enviable safety record: from how aircraft are designed and certified, to airline standard operating procedures and maintenance practices, to standards for airport infrastructure and a strong air traffic control system. All of the principles of the Safe System Approach of the National Road Safety Strategy have already been adopted by commercial aviation: that death and serious injury are unacceptable, that humans make mistakes, that humans are vulnerable, responsibility is shared, security is proactive, and redundancy is critical.
This approach has been so successful that even proponents of autonomy don’t really talk about making flight operations safer. As manufacturers and airlines consider single-pilot and ultimately fully autonomous operations as a way to cut costs and circumvent a future shortage of pilots, from a safety perspective their focus will be to ensure the same level of security that exists today. .
Related: A very real pilot shortage threatens to upend the recovery of American airlines
Automakers have “a different bar than ours, they have to be better than 40,000 [annual road deaths]we have to be as good as zero,” Boeing Vice President of Aircraft Development Mike Sinnett said in 2017, discussing the company’s autonomy strategy.
Range seems to promise greater safety benefits for small aircraft like eVTOLs, as small aircraft crash much more often than airliners, and usually for reasons called “pilot error”. However, when you look closely at these crashes, it is evident that the pilots were operating in a much less robust system than that created for commercial airlines.
Take the January 2020 helicopter crash that killed nine people, including Kobe Bryant. The Part 135 on-demand flight through the Los Angeles metro area was a prototypical urban air mobility mission, in a market targeted by several eVTOL air taxi developers.
The NTSB identified the probable cause of the crash as the pilot’s decision to continue visual flight in instrument meteorological conditions, resulting in his spatial disorientation and loss of control. But it was also working in a system that lack of practical instrument flight rules infrastructure for helicoptersand under the kind of pressure to accomplish the mission that airline pilots are well insulated from.
While an autonomous aircraft would presumably not have succumbed to spatial disorientation, it would also not have been allowed to randomly enter clouds. The system overhaul that would be needed for effective low-level operations by autonomous aircraft would also make it safer for manned aircraft, undermining the apparent safety logic to get rid of pilots.
While it’s true that human pilots make mistakes, many of them, developers of autonomous aircraft may have a tougher road ahead of them than they’d like to admit. In one paper Published last year, Jon Holbrook, a cognitive scientist at NASA’s Langley Research Center, pointed out that most of what we know about human performance in aviation comes from studying mistakes and failures. relatively rare, ignoring the many ways humans contribute to safety.
As an example, he cited an analysis of online operational safety audit data indicating that airline pilots intervene to manage aircraft malfunctions on 20% of normal flights. Extrapolation from this data suggests that these pilots intervene to ensure flight safety more than 157,000 times each time pilot error contributes to an accident resulting in hull loss or fatality.
“An assertion… that human error contributes to accidents, so removing humans will reduce accidents, ignores that humans are also an important source of successful system performance and in fact contribute to safety far more than they reduce security,” Holbrook wrote. Removing pilots from the cockpit entirely will likely be much more difficult than previous leaps in automation which, for example, eliminated the need for flight engineers.
Autonomous systems will undoubtedly continue to improve. Tuesday, Sikorsky announcement that in collaboration with DARPA, it had performed the first fully autonomous flight of a UH-60 Black Hawk helicopter without a safety pilot on board, using Matrix autonomy technology which it has also deployed on small aircraft commercial as a Heavily modified FedEx Express ATR 42 to test single-pilot operations.
Related: FedEx, Sikorsky Quietly Begin Single-Pilot Testing For Cargo Airliners
Developers of these technologies are also taking a fundamentally different approach than that which underpins many automated systems in today’s aircraft, which rely on human pilots to intervene quickly and correctly in the event of system failure – as was the case with the characteristic augmentation system of maneuver of the 737 Max. More robust and reliable automation could eliminate the need for pilots to intervene so frequently to deal with aircraft malfunctions in the first place.
Nonetheless, presenting autonomy as a solution to pilot error is a distraction from the requirement to, in DOT’s words, create “a redundant system to protect everyone.” Even with fallible human pilots taken as a given, if UAM operators can translate the protections of the Part 121 world into Part 135 operations, they will succeed in achieving the level of security they deem necessary for public acceptance.
Whether they can make a profit is a separate question. The real test of autonomous aircraft will not be whether they can make a faulty system safe, but whether they can make a safe system affordable.
Write to Elan Head at [email protected]