Posted 7 years 36 days ago ago by Randy Mains
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 problem.
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 out:
“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!
Randy Mains is an author, public speaker, and a CRM/AMRM consultant who works in the helicopter industry after a long career of aviation adventure. He currently serves as chief CRM/AMRM instructor for Oregon Aero. He may be contacted at [email protected]