Fatigue management in the airline industry: pilot fatigue
Tuesday, September 02, 2014 by Rhonda Locke
This is the second in a series examining the impact of fatigue on industry. In this issue we discuss the dangers and frequency of pilot fatigue when flying commercial passenger and freight aircraft.
When the average passenger boards a commercial flight, they do not imagine the person or people in the cockpit could be suffering from fatigue or be likely to enter the dangerous state of drowsiness while in charge of their aircraft.
Of course, pilots are not exempt from the condition which affects everyone almost every day. Throughout history there have been a number of airline crashes where pilot fatigue has been attributed as the underlying cause.
The Japan Airlines accident
Many years ago I worked for Japan Airlines, an airline which experienced the worst-ever single aircraft accident almost 30 years ago. The crash happened in a mountainous area of Gunma Prefecture and caused the death of 520 passengers and crew, an absolutely devastating tragedy for the airline, the families and the whole of Japan.
The airline took many years to recover and each and every staff member took the catastrophic accident very seriously. Indeed, each new class of pilots participated in an expedition to the mountain when they first joined the airline so they could reflect on the responsibility for human life each was about to assume. While this accident was attributed to mechanical failure and not pilot fatigue, it further highlights the dangers faced if pilots are not operating at their maximum capacity.
As with other industries, it’s not necessarily the nature of the work which causes drowsiness, but the compounding impact of sleep deprivation over time or it can be caused by an excessive period of time awake before actually starting work.
In the specific case of airline pilots, it has been determined many face a long commute to the airport before they start work and this may cause an individual to experience drowsiness even though they have only technically been working for a few hours. They also battle with jet lag caused by crossing multiple time zones in a normal 24-hour period.
As with other professions, sleep disorders may also adversely affect pilots, of course, given they may be in charge of a large passenger jet and responsible for many hundreds of lives in the air, a mistake can prove disastrous.
Continental flight 3407
On 12 February 2009, pilot mistakes caused by fatigue resulted in such a disaster. Continental flight 3407 stalled and plunged into a house five miles north-west of its intended destination in Buffalo New York, killing pilots, crew, all 45 passengers on board and one man on the ground.
According to the accident report, the pilots had failed to properly respond to cockpit warnings the plane was moving too slowly through the air. Additionally, the report stated prior to the flight, both pilots had long commutes and slept in the crew lounge, instead of a hotel.
Micro sleeps at 30,000 feet
Studies undertaken into performance while operating aircraft have determined a number of pilots have suffered micro sleeps or have actually fallen asleep while in operation of an aircraft. The Brazilian Association of Civil Aviation Pilots (Abrapac) reported 57% of Brazil’s commercial airline pilots have nodded off during national flights and this figure increases to 70% during international flights. The study showed the major cause for Brazil's pilots was irregular shifts, which can aggravate existing fatigue and cause a person to move into the dangerous state of drowsiness.
Long work days, night shifts, insufficient rest times between shifts and an average of four consecutive nights of work were the pilots’ major factors causing concern.
Unfortunately, after four consecutive night shifts it was determined a pilot is approximately 36% more likely to have an accident than having worked one night shift.
Another study commissioned by the National Transportation Safety Board in the US surveyed UPS pilots. This was in response to the crash on approach to Birmingham airport in August 2013 which killed both pilots on board. While the crash investigation determined fatigue was not the underlying factor, the resulting study revealed pilots felt tired, overworked and afraid if they complained or called in sick, they would face company retaliation.
Although the risk of accident increases with an increase of drowsiness levels, many of these micro sleeps thankfully do not result in a tragedy. “Autopilot” can effectively fly a plane for the most part of a long-haul flight. Of course this is not always the case, and drowsiness impairs judgment and decision making if something goes wrong during an otherwise routine flight.
The British Airline Pilots Association (BALPA) is currently investigating the effect of fatigue on pilot and aircraft safety. Optalert’s General Manager of Scientific Research Dr Andrew Tucker is collaborating with them and research partners, the University of Paris Descartes, and Swinburne University to evaluate pilot drowsiness at work and on the commute from work to their home. They are using Optalert’s drowsiness detection technology to measure the following:
How tired is too tired or how drowsy does a pilot need to be to operate a plane safely
The effect on one pilot if another pilot involuntarily falls asleep and the dangers facing pilots driving home after they have worked long shifts.
We’ll be monitoring this investigation closely and will post the results as they are made public. It’s a subject of great interest – especially for those of us who travel frequently.