Findings from a Night Study

by Ray Oyung

December 29, 2000

We've finally added the finishing touches to our simulation study that was conducted to see if pilots would be more alert during night flights if they were given a break every so often. Seems like common sense but no one has ever conducted a study to empirically (that means to verify something through an experiment) determine if taking a break at different times throughout the flight would help pilots stay more alert.

Our study was conducted with real airline pilots who we picked up and brought into our lab at nine o'clock at night. They woke up during their normal wake up time (around seven or eight o'clock that morning) and didn't take any naps or drink any coffee (which can help make someone more alert). Two pilots would fly our simulator at a time (see Planning a Simulator Study, Feb. 98 for more details on the simulator). We gave the pilots data collection instruments to use during the study that consisted of an actigraph which collects information on each pilot's movement. It is a device similar in size to a wristwatch that they would wear several days before and during the flight. We attached electrodes to different places on their head to measure brain wave activity. This collection of brain waves is called electroencephalography (electro - encephalo - graphy...yikes...it's a big word...many people prefer to call it EEG instead). This information allows us to determine if and when they may fall asleep. Every so often the pilots would take a sustained attention test to measure how well they were performing. Also, there were questions the pilots would answer periodically asking how alert or sleepy they felt.

After we told them what to expect during the experiment, they climbed into the simulator around two o'clock in the morning. Some of the pilots received planned rest breaks during the flight. Some only received one break. Each group landed around eight o'clock in the morning and after taking off the data collection instruments, we would drive them back home or to the hotel they were staying to get some rest. Could you imagine staying up for over 24 hours without sleep and trying to drive? Some people actually do this, but it's not very safe. I remember a few times when I had to stay up that late and barely was able to walk straight let alone attempt to drive!

After we finished collecting the data, we decided how to run some statistics to help us determine what all the data we collected could tell us. We found that planned activity breaks could help pilots stay more alert. This is what we found physiologically based on the data collected from EEG (what their bodies told us) and subjectively from pilot responses to our questions (what their minds told us). The breaks helped most during the later portion of the simulated flight. All of these findings are written into a report for anyone to read and study. Our hope is that this type of research will help answer some question on how to operate safely in an aviation environment and provide a way to instill more questions into the folks who together provide us with air travel. The goal is to make it safer for not only everyone who travels by air, but also for those of us who are on the ground underneath it all.