There is scant attention given to it. Most pilots overlook it. Some shrug it off. While others simply don’t know about its effects in the cockpit. The problem? Pilot dehydration. Most pilots are unaware of its devastating effects and symptoms, which can increase the risk of aircraft incidents and accidents, even during a mildly warm day. So in order to heighten general aviation’s awareness of this often-overlooked condition, the Federal Aviation Administration (FAA) has recently added pilot dehydration to its list of physiological conditions found in the latest Practical Test Standards—its symptoms, causes, effects and corrective actions. It believes that educating pilots about dehydration will not only decrease aircraft incidents, but also save your life one day. 

Most pilots associate dehydration with thirst and assume that an easy fix is just to drink any type of liquid. This is not always the case. A pilot’s dehydration condition can be caused by a lack of water within the body cavity due to high body temperatures, a dry aircraft environment, excess caffeine, antihistamines, inappropriate fluid intake and other factors. Many soft drinks, teas and juice drinks do not constitute good hydration substitutes, as they contain caffeine and sugar that may compromise absorption of the water content. 

Hot cockpits and flight lines also cause dehydration. The 130-degree ramp at Phoenix, Arizona., for example, is an obvious cause of dehydration. But what about the 72-degree cockpit? Pilots should concern themselves in that environment, too, since average humidity in the cockpit is low, causing a dramatic increase in fluid loss. 

The symptoms of dehydration go beyond thirst. In an effort to respond to the brain’s need for fluid, the kidneys reabsorb water through the urine, creating fluid retention and frequent urges to visit the bathroom. Dry skin is also an indicator of dehydration, as the skin gets most of its moisture subdermally. The brain is 75 percent water and, when it needs to replace lost fluid, it can manifest certain symptoms, such as headaches, light-headedness and fatigue. Dehydration also contributes to fuzzy thinking, poor decision-making, dizziness and muscle fatigue. Long-term effects include wrinkled skin, impaired memory function, dry hair, brittle nails, constipation, susceptibility to colds and, because of extremely dry nasal passages, sinus infections. 

So how do you avoid dehydration in the cockpit? You’ll need to permanently attach yourself to a water bottle and drink from it regularly. The Federal Air Surgeon Bulletin suggests drinking cool, 40-degree Fahrenheit water before feeling thirsty. This will help you stay ahead of the game, keeping you hydrated before the “thirst mechanism” sets in.  

But, perhaps, the most important factor in preventing dehydration is to continually be aware of your physiological and environmental conditions. This will help to maintain your rehydration water intake and prevent you from progressing into heat exhaustion and even heat stroke. It’s a good plan for a problem that can easily be avoided—all with just a few gulps of water.