“Advances in several key technologies, most notably automation, have doubtlessly contributed to aviation safety and eased pilot workload. However, significant advances will be required in automation and other technologies for airline and air transport operators to reduce the number of pilots in the cockpit without compromising safety,” the paper says. “Until automation technology can provide the same level of situational awareness, communication, and judgment as humans, two pilots in the cockpit remain a necessity for achieving maximum safety.”

ALPA says the two-pilot system improves the safety of the airline industry by giving pilots the ability to share their workload and providing redundancy during emergencies. It also provides redundancy if one of the pilots becomes incapacitated en route.

The paper also outlines ways a one-pilot policy could compromise safety, saying among other things that a single pilot is likely to rely more heavily on automation, which could make regaining control of the aircraft in an emergency more difficult. The paper states that over-reliance on automation usually reduces a pilot’s situational awareness. Single-pilot and highly-autonomous cockpit systems also present more cybersecurity issues than a traditional two-pilot flight deck.

Experts agree that the two-pilot system is the safest and most efficient way to manage aircraft today, but as technology advances, that may not always be the case. Richard Aboulafia, an aviation analyst with the Teal Group, said single-pilot operations are definitely part of the long-term outlook for the aviation industry.

“Hanging over all of this is the very high level of likelihood that this will happen. I’d be shocked if we had a two-crew flight deck in the 2040s,” he said.

But, Aboulafia acknowledged the industry will have to overcome many of the hurdles ALPA identifies in its paper before commercial flights can be managed by a single pilot.

“Obviously everyone’s going to have to have that iron-clad remote backup connectivity,” he said, “so if there is a tragedy that happens as a result of pilot heart attack or other incapacitation, everyone is comfortable that the backup is as good as a copilot.”

Aboulafia said a ground-based operator could theoretically take control of a single-pilot plane in some emergency situations, but aircraft designed for that setup would still to require a high level of autonomous backup technology. If the lone pilot became incapacitated or the plane’s connection with the ground was lost, the aircraft would have to be able to return to the airport or complete the journey by itself.

Even once planes are technically capable of single-pilot or fully autonomous flight, passengers still have to be comfortable with the technology if airlines hope to viably introduce it into commercial service.

“Passenger perception is going to matter, and that’ll be the last hurdle,” Aboulafia said. He acknowledged that ALPA’s paper may be part of an effort to sway public opinion against single-pilot and autonomous flying. It is not in the union’s interests if new technology enables airlines to halve the number of pilots required for every flight.

For now though, ALPA has public perception on its side. The white paper notes repeatedly that based on survey data, the general public does not currently feel comfortable with the idea of single-pilot flights.

Scott Winter, an assistant professor at Embry-Riddle Aeronautical University, whose research focuses on the consumer perception of automation, agrees with ALPA’s assertion in the white paper.

“In general consumers are not yet willing to fly on autonomous aircraft, fully autonomous aircraft or even remotely-piloted aircraft,” he said. “They did seem rather neutral in terms of it being used in a cargo capacity, so that may be one area where you see attempts being made to promote public confidence.”

Other stakeholders will have to be comfortable with the possible risks of a higher level of automation, too. Insurance companies, for example, will have to be confident in the technology’s reliability.

Winter also said that it would be prohibitively expensive to modify current airline fleets for single-pilot or autonomous flight, so such planes would likely have to be designed from scratch. To retrofit a current commercial airplane cockpit for single-pilot or autonomous flight would require more than just new computer systems. It would also mean rearranging instruments, indicators and controls to a place where a single captain could easily reach or see all of them without the assistance of a co-pilot.

“You’re going to be looking at the manufacturers having to design a new aircraft,” Winter said, and added that doing so is usually at least an eight-to-ten-year process.

Winter noted though, that airlines, manufacturers and regulators are working to shape public opinion on single-pilot and autonomous flying much farther in advance of its introduction than they have for other new technologies.

“Rarely has the consumer perspective been a focal point early on,” he said, noting that new technologies are often introduced with low public awareness, and then campaigns begin to convince consumers of their benefits or drawbacks.

“There’s been a lot of talk around it recently,” Winter said, but that doesn’t mean your next commercial flight is likely to have a single pilot. “I would guess that we’re still decades away from that, probably at least 20 years.”

Featured photo of an Airbus A350 flight deck by Richard Baker/In Pictures via Getty Images