Fatigue and Dehydration

For the past weeks we have discussed various things that can transpire with our aircraft, so now it is time to turn our attention to ourselves as pilots in keeping with the responsibility to provide a safe environment for us and our passengers. Two mahor factors that can greatly affect our performance this time of year in particular are fatigue and dehydration. If you fly during the heat of the day, the lack of fluids in your system can be very detrimental to decision making.

The most common causes of fainting or becoming dizzy while flying are:

  1. a decrease in blood pressure
  2. a change in heart rhythm
  3. dehydration

The first two causes can be exacerbated by fatigue, expecially during times of high work load. Both blood pressure and heart rate change with altitude so don’t increase this situation by flying tired. With the availability of bottled water, there is no excuse for the third to occur.

Say you have been on a weekend trip and your return flight is going to be in the evening so you can beat the heat — try to take a 1 to 2 hour siesta before your departure. I’m sure you’ll agree that after a long day in the heat (beach or lake) followed by a transition into a cool environment (evening at altitude) you will feel tired and relaxed within 30 minutes. This is no time to be confronted with decision making. On your way to the airport drink some water. By the end of a summer day if you have not had at least six to eight 8oz. glasses of water you run the risk of dehydration and becoming faint at altitude. Also take water along on cross country trips. Don’t allow the fear of having to use the restroom be a deterrent. Either take a port-a-can or schedule more stops.

In case dizzyness should occur you should already be flying as close to perfect trim as possible. Get used to flying with the heading bug on the direction in which you are flying so you can activate the auto pilot (if available). Bend over and hold your head as low as possible to increase blood flow to the brain. On trips you should also have a small first aid kit which should contain smelling salts. These will increase your heart rate temporarily affording precious seconds to regain your composure. Preventive maintenance for yourself as well as your aircraft helps to insure that you and your family or friends, as they say, arrive alive.

Reference: Common Sense. As coincidence would have it, during a break half way through writing this I read an article in the new AOPA Pilot titled “Feeling Faint” (http://www.aopa.org/members/files/pilot/2003/prof0307.html).

These safety tips are provided by the WCFC Safety Committee. They are intended to stimulate thought and discussion about flight safety and do not necessarily represent club policy nor are they intended to replace instruction from a qualified instructor.

Fatigue and Dehydration