Posted 6 years 238 days ago ago by Admin
I’d been awake for 17 hours when the phone rang at 12:45 a.m. The
communications specialist said, “There’s a scene call on Palomar
Mountain. Will you be able to take the flight?”
“Well, I’ve only had one shot of Tequila, but let me check the weather and I’ll get right back to you.”
Sound implausible? The shocking
truth is that it’s not—not when you consider a study published in the
British Journal of Occupational and Environmental Medicine, where
researchers in Australia and New Zealand determined that from 16 percent
up to 60 percent of road accidents involve sleep deprivation. This
reflects some of the same hazardous effects as being drunk. Although I
had never actually had a drink that night, my cognitive thinking, my
body, and reflexes were as adversely affected as if I had.
The researchers found that people
who drive after being awake for 17 hours to 19 hours performed worse
than those with a blood alcohol level of .05 percent. They discovered
that after longer periods without sleep, performance decreased to levels
equivalent to the maximum alcohol dose given to test subjects with a
blood alcohol level of 0.1 percent. In short, the sleep deprived are as
impaired as those who are legally drunk. The study also found that
getting less than six hours of sleep a night could affect coordination,
reaction time, and judgment, posing in their words, “a very serious
risk” (italics mine). That’s something to consider before piloting a
helicopter, don’t you think?
I highlight this topic because a
recent helicopter pilot fatigue survey conducted by Rotorcraft Pro
generated a shocking finding: 91 percent of shift-working helicopter
pilots said they experience fatigue while on duty and a full 48 percent
indicated they experience it on shift either “very often” or “often.” If
the survey is representative of the general helicopter air crew
population as a whole, there appears to be an epidemic of crew fatigue
in our industry. This means there are flight crews operating at less
than 100 percent capability. That’s one scary thought!
Airlines Take Fatigue Seriously
The effect of crew fatigue on
airline flight safety changed dramatically on 12 February 2009, when a
Colgan Air Bombardier DHC-8-400 crashed into a residence in Clarence
Center, New York. Two pilots, two flight attendants, and 45 passengers
were killed, triggering a wave of inquiries into the operations of
regional airlines in the United States.
The National Transportation
Safety Board found the probable cause had a direct link to the two
pilots being overly fatigued, causing the pilot flying to actually fail
to monitor the plane’s approach speed. This stalled the aircraft, then
the recovery was mismanaged by overriding the stick shaker and actually
pulling back on the yoke instead of pushing it forward, thus only adding
75 percent power, not full power. Meanwhile, the pilot monitoring
retracted the flaps without conferring with the captain, exacerbating
The pilots’ family members took
their concerns all the way to Congress. Appalling commuter pilot working
conditions, long duty hours, sleeping in departure lounges, and other
issues were exposed, This prompted the Airline Safety and Federal
Aviation Administration Extension Act of 2010 that requires better
commuter pilot crew rest.
Two years ago, when attending a
human factors CRM course at the American Airlines Training Academy, one
of the hot topics was crew fatigue. I was impressed with how seriously
the airlines treat crew fatigue: They pay their flight crew $1,000 not
to come to work if they are fatigued.
To gauge crew fatigue before
going on duty, the airlines use tools such as an Aviation Fatigue Meter
app created by Pulsar Informatics. Employees answers 20 questions to
determine their level of fatigue and the program relates it to a
hypothetical amount of alcohol consumption. More information can be
found at fatiguemeter.com.
The NASA Nap
A groundbreaking 1995 NASA study
headed by Dr. David Dinges at the University of Pennsylvania School of
Medicine looked at the beneficial effects of napping for astronauts. The
study report stated:
"… sleeping on average 26
minutes, to our amazement, working memory performance benefited from the
naps, but vigilance and basic alertness did not benefit very much.
Working memory involves focusing attention on one task while holding
other tasks in memory ... a fundamental ability critical to performing
complex work like piloting a spaceship. A poor working memory could
result in errors.”
That’s something we helicopter pilots should well consider before accepting a flight.
The NASA study further found that
the total amount of sleep in 24 hours remained the most critical factor
for vigilance and alertness, which are defined as the ability to
maintain sustained attention and to notice important details.
Working the Night Shift
Another interesting finding was
that naps didn't work as well for volunteers on a nocturnal schedule.
The out-of-sync volunteers had a very hard time waking from naps, and
the grogginess of sleep inertia lasted for up to an hour. Dinges points
“Some sleep inertia did occur
after naps on a normal schedule too, but the inertia after a nighttime
nap was much more severe. Naps are a short-term fix, offering only
temporary boosts in mental acuity. They cannot replace adequate recovery
sleep over many days. In the end, there's no substitute for eight sweet
hours of shut-eye.”
What Can We Do?
Ensure you get your rest and
self-assess. Remember, in terms of performance, being awake for 17 hours
is similar to having a blood alcohol level of 0.05 percent, and being
awake for 24 hours is like having a blood alcohol level of 0.10 percent.
You know not to operate an automobile if you are legally drunk, so you
definitely should not be flying a helicopter. Be aware of the dangers of
lack of sleep. You owe it to yourself, to those who entrust their lives
in your care, and to those you love.
Safe Flying … and Sleeping!