by Dr. John Beasley, M.D.
Aviation Medical Examiner
Professor Emeritus and Clinical Professor
Department of Family Medicine
University of Wisconsin – Madison
You’re not as bad when you’re not dog tired,” said my friendly examiner when I took an IPC (Instrument Proficiency Checkride) a few years back on a sunny Saturday morning. Often before that I had done them in the evening after a full day’s work – and the fatigue showed. At least I hoped it was the fatigue.
Now, I don’t take night hospital calls or deliver babies these days, but back when I did, I had a rule of “No flying if less than five hours of sleep.” Pretty arbitrary, but the rule probably made sense. I still have the rule, but don’t have to invoke it as often.
So what happens with fatigue? It can be insidious. Back in college, I would pull occasional “all-nighters” and an interesting thing would happen the next day – I would have “micro sleeps” – short episodes of sleep that would come even without feeling particularly tired – but I would realize that I had not heard anything the “prof” had said for the last 5 minutes or so – and you could see where my pen had dribbled off the notebook. And even if you are not actually falling asleep on final approach, there are clear decrements in your attention and performance that will pose hazards.
As a private pilot, you could go out and fly even if so tired that you have trouble staying awake on the drive to the airport. Not a good idea!
Some years ago I had worked a full day and it was late in the evening, well after dark, when I dropped off a colleague in Wausau (Wisconsin). I botched the landing, which was very noticeable, as I was flying a Cessna 180 in those days. I came to what was (for me) a surprisingly smart decision. I called it a day, and took a motel for the evening, rather than doing another leg home that night. The times I wasn’t that smart I guess it all worked out as the airplane could be used again, but it still wasn’t a good idea.
For airline pilots, the FAA has long recognized the problem of fatigue. See http://www.faa.gov/news/press_releases/news_story.cfm?newsId=13272 for the detailed bureaucratic rules. They actually make some sense, and the rules depend on time of day, workload (number of segments), total time during the week and so forth. They include, for a rest period, “…10 hour rest period of which 8 hours is an uninterrupted sleep opportunity.”
Even with adequate time of rest, jet lag is an important issue for pilots flying long distances or with people doing shift work. (Or, those with small children getting them up at night, which can cause some of the same problems!)
It’s important to note that sleep deficit can be “cumulative.” Most of us will tolerate a single night of too little or poor quality sleep, but if this goes on for several days, the decrements in performance increase.
So, my suggestions: First, be sure you have enough time allocated to get a good 7 to 8 hours of restorative sleep. Don’t let your busy life get in the way of adequate rest. It doesn’t pay off in the long run.
If the quality of your sleep is an issue, then go to Google and look up some material on “sleep hygiene.” One site is: http://www.sleepfoundation.org/article/ask-the-expert/sleep-hygiene. Among other things, be sure that you get at least some exercise during the day so you are physically tired, but perhaps not right before bedtime.
During the winter, try to get outside during the day so you get adequate light exposure.
If there are psychological problems keeping you awake – which happens to all of us occasionally – get some counseling as to how to deal with them. That won’t have adverse effects on your certification, although you should bring a letter from your counselor so the examiner knows that you are doing well. If there is significant depression or other problems requiring medications, that’s another story.
For rare insomnia, you can use a sleep aid such as zolpidem (Ambien), but not more than two (2) times a week and then you must let 24 hours lapse between when you take the stuff and when you get in the left seat. You can’t be using it for time zone adjustment. By the way, most over-the-counter sleep drugs are sedating antihistamines, which are a real no-no as they have significant and lasting adverse effects on performance.
And, there is nothing wrong with caffeine if you are feeling a bit sluggish – but it’s not a sleep substitute. It does increase alertness.
