Fantastic Tech Is Making Pilot Fatigue Even More
Perplexing
DURING A MID-AUGUST afternoon in 1993, American International Airways
Flight 808 prepared to land in Guantanamo Bay. Procedures required that the
pilot execute a visual approach over the sea that included a late right turn
toward the runway, to avoid entering Cuban airspace, less than a mile to the
west. The crew, who had been awake for over 19 hours continuously, overbanked
the Douglas DC-8-61 freighter, lost control, and crashed. An investigation by
the National Transportation Safety Board determined that the impaired
decision-making demonstrated by the three crew members, all of whom were
injured, was due to the debilitating effects of fatigue.
Today, fatigue remains a problem for pilots and a risk to the flying
public, but incomplete science and the positive effect of aviation technology
make the best solutions hard to see.
Managing fatigue hasn't always been about preventing accidents. During the
Industrial Revolution, long workdays prompted calls by social reformers for a
more equal distribution between work, recreation and rest, calls that eventually
led to the establishment of an eight-hour workday.
A century later, fatigue came under the scrutiny of scientists. NASA
dedicated a research program to understanding the phenomenon amongst pilots. The
effort was groundbreaking for its time, as researchers studied the effects of
sleep loss and interruption on muscle activity and brain function. They found
that when it came to alertness in the cockpit, the conditions in which pilots
flew mattered as much as the time they spent at the controls. These findings
facilitated a major change in how fatigue was managed on the flight
deck.
Achieving the type of deep restorative sleep necessary to avoid fatigue
requires that muscles relax, body temperature fall, and brain activity drop.
Longer periods of rest between shifts gives the body the chance to do that.
Limiting the total amount of flying required of pilots each month also reduces
the chances of fatigue building up over consecutive work cycles.
In 2011, the Federal Aviation Administration (FAA) placed its strictest
limits to date on night flying by commercial airline pilots, because working
when the sun's down is more fatiguing than doing the same during the day. US
carriers must give their pilots longer rest opportunities prior to flying (ten
hours compared to eight previously) and provide them 25 percent more continuous
time off each month. Advocates contend that today's rules improve safety. The
Air Line Pilot's Association, the world's largest pilot union, lauded the new
FAA rules as "a significant victory for safety and the traveling
public."
Such rules may seem great when it comes to keeping the skies safe, but it's
hard to know they are adequate. One problem is the lack of agreement among
scientists as to what fatigue actually is. Some call it a process, others a
state. Some treat it as being synonymous with sleepiness, others see it as a
"moral disorder" that weakens willpower and leads to physical
exhaustion.
Modern tools aren't a perfect solution. New psychometrics tests can measure
how alert a pilot is. "Actiwatches," small wrist-worn devices, can record a
flight engineer's sleeping patterns for months at a time. Questionnaires gauge
how tired crew members believe themselves to be. Yet, Dr. Atul Khullar, a fellow
at the American Academy of Sleep Sciences points out, points out, "the extent to
which these techniques accurately predict how safely an airplane is flown is
less clear."
It's hard to be sure we're addressing fatigue properly,
because-ironically-commercial aviation's remarkable safety record makes the
answer hard to find. More than 37.6 million commercial flights took to the skies
in 2015, a new record. The global accident rate-measured as the number of
aircraft lost per one million flights-was just 0.32, one of the lowest in
history. Long-term trend data suggests flying is getting even
safer.
This rarity of accidents is a testament to technological progress,
especially improvements in airframe construction, propulsion mechanics, and
avionics design. It also means proving that fatigue reduces safety is difficult,
because those technologies lessen the potential fallout. The highly automated
nature of flying today means aircraft flown by weary pilots will almost
certainly still reach their destinations safely.
Addressing these issues will not be easy, but it is necessary, because
fatigue can make flying more dangerous. In its report on the 2007 crash of
Colgan Air Flight 3407, which killed all 49 people aboard and one person on the
ground, the NTSB found a variety of causes, and concluded that "the pilots'
performance was likely impaired because of fatigue."
Even with better information on how to manage fatigue, those efforts face
opposition from the industry because they add expenses to airline balance sheets
that are already in the red. The 2011 FAA rules for example, forced carriers to
hire more crew and place extra staff on reserve, to the tune of $300 million.
That's hardly chump change for an industry that saw a mere four percent profit
(or $8.27 per passenger) the year the rules went into effect. As long as this
continues, managing fatigue will continue being a prickly affair.
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