Controversial opinion; your safety devices may be making you less safe.
On a flight to Melbourne for the Australian International Airshow, I’m listening to an episode of the podcast “Cautionary Tales with Tim Harford”. This episode, titled “When the Autopilot Switched Off” looks into the circumstances surrounding the tragic crash of Aeroflot Flight 593, an Airbus A310 which crashed in 1994, killing all 75 people on board.
Investigations into the cause of this accident revealed that an off-duty pilot entered the cockpit with his two children during the cruise, in days prior to 9/11 where cockpit security was far more relaxed. With the autopilot engaged, the crew permitted the children to take turns at sitting in the captain’s seat, conscious of the fact that with the autopilot engaged, the aircraft would not respond to the children’s inputs as they maneuver the control column. This is, until the second child applies a more abrupt control input, which partly disconnects the autopilot. This goes unnoticed by the crew, as the autopilot disconnect light illuminates. Moments later, the aircraft is spiraling out of control. The copilot, who had previously rolled his seat rearwards, is unable to reach the controls and the only person within reach is now a 15-year-old child, receiving shouted instructions by a pilot pinned by G-forces to the rear of the cockpit.
So how could this be permitted to occur? To better understand factors that may have contributed to this accident, we need to take a look at the history of safety equipment and what we can learn from safety statistics over this time.
In 1966 the fitment of seatbelts in cars was mandated in the US. In the following years, economists conducted studies to understand the impact of these mandates and – controversially – found that no lives had been saved. This did not go to say that seatbelts weren’t working, in fact the data showed that drivers wearing seatbelts were more likely to survive an accident. However, the data showed that following the introduction of seatbelts, drivers were now having more accidents. Data further suggested that when safety improvements are implemented, 20-40% of the benefits may be lost by people pushing the envelope of these benefits. This later became known as the risk compensation theory, or Peltzman Effect; the concept that when humans feel protected, we take more risks.
This concept raises the question; how might this theory apply to recreational pilots? Unfortunately, it doesn’t take long to identify a range of scenarios where risk compensation may be having an impact on our safety.
The first scenario that comes to mind relates to the advancement in systems to inform pilots of the position of other aircraft. TCAS, ADS-B, FLARM, and EFB traffic information. Despite the development of these systems and the relatively common uptake of use in recreational and general aviation aircraft, near miss and mid-air collision events continue to rate highly in accident and incident data. So what impact is the fitment of this technology having on how pilots operate, and is this resulting in a new level of complacency? There is no doubt that these systems have a positive effect on situational awareness, but with more and more technology inside the cockpit, pilots are tempted to spend more time focusing on this equipment rather than ensuring they continually perform a regular scan outside. That dot on our iPad indicating the location of another aircraft may just be resulting in fixation on that one known target, leaving us unaware of the presence of another, unmarked aircraft, closing in rapidly on our position.
I can’t help but wonder how other safety advancements impact our daily decision making. As engine systems become more reliable, are we more inclined to take the route over rugged terrain or fly at lower altitudes? With improvements in airframe strength and aircraft stability, are we more inclined to push the envelope with more extreme maneuvering? With fitment of better seatbelts and improved crashworthiness, are we more inclined to operate into and out of marginal airfields, in stronger wind conditions, or at low level? With enclosed cockpits, improved weather forecasting systems, autopilot fitment, and terrain awareness, are we more inclined to push on into deteriorating weather? Is our human response to safety equipment counteracting the impact of these advancements?
This argument does not go to say that safety equipment should not be embraced by pilots, in fact quite the contrary. What is important, however, is that when we rely on safety equipment, we make an active attempt to understand how the system works, any limitations of this equipment, and how it may further impact our decision making.
For Flight 593, the children of an off-duty pilot would never have been permitted to sit at the controls if it weren’t for the fitment of an autopilot. As the aircraft crashed into terrain in Siberia, the autopilot, despite being partially disconnected, could have in fact recovered the aircraft from its upset state, if only the autopilot had detected no control inputs. All that had to be done to recover was for everyone to let go of the controls. The safety equipment that was originally over-trusted when the children were permitted to sit at the controls wasn’t trusted enough when it counted the most. Safety equipment saves lives, just don’t allow the fitment of such devices to modify your behaviour into taking more risks, just because you feel protected!
