In a major aerospace medicine text I have, air sickness is defined as a state of diminished health characterized by specific symptoms that occur in conjunction with and in response to unaccustomed conditions existing in ones motional environment.
The pilots translation of this is puking your guts out, aka the power yawn or just plain urping on your shoes.
Air sickness is a common reason why student pilots quit and why many potential pilots never even start training. Its also a frequent problem for neophyte aerobatic pilots and affects passengers even more often, to the extent that a surprising number of aircraft owners cant coax spouses or children into their airplanes.
While I was an activist in college, I learned about sick passengers firsthand when I took a nun aloft to document strip mine erosion. When she turned green, I instantly realized why other pilots carried sick sacks and why Id better start. The experience cost me a set of Jepp charts, since my flight bag was the only container handy at the time.
Now that we have a pill to replace lost hair and another to prop up other sagging body parts, surely there must be a sure-fire cure for air sickness. The truth is, there are good remedies. But it may take some experimentation to determine which one is best for you or your passengers. As a pilot, you have legal limitations to consider, as well. Motion sickness is a learned malady.
For instance, adults who have grown up in child safety seats which elevated them to a level where they could see out the side windows of a car have a lower incidence of motion sickness than do those who grew up before car seats or whose parents didnt use them. Fortunately, since air sickness is a learned process, it can be unlearned.
Symptoms generally follow a path of increasing severity terminating in vomiting and even passing out. Headache, increased salivation and swallowing, eructation (a nice medical word for belching and burping), flatulence (no definition required) and cold sweats are the most common antecedent symptoms. Precipitous vomiting can occur without other symptoms and is the hallmark of space-flight induced air sickness. What causes motion sickness? Our balance and spatial orientation are determined by a complex system which includes our brain, our eyes and, in particular, the semicircular canals of the inner ear. The three tubes are oriented essentially in three planes -0, 45 and 90 degrees to the axis which runs from the top of the head to our feet.
The tubes are filled with a thick fluid and are lined with microscopic hairs which are gently bent by the fluid, which tends to stay put when the head moves. The primary inducement to motion sickness is mechanically perceived linear and angular acceleration.
The original theory of motion sickness focused on sensory conflict and neurological mismatch, to include the discrepancy between anticipated and actual orientation. Being able to anticipate the discrepancy confers a certain amount of immunity to air sickness, which explains why pilots actually handling the stick dont get sick as often as the passengers do.
When an instructor does the first stall with a student, a puke fest is less likely if the CFI has carefully prepped the student on what to expect. Some people get sick just due to abnormal stimulation of vision such as encountered in a non-motion simulator. The absence of outside visual reference is also a stimulus for air sickness.
Age is also a factor. Susceptibility to motions increases from birth to puberty and decreases thereafter. So does hearing acuity, so the two may be connected in some way. Women are generally more susceptible than men. Having eaten just prior to flight appears to worsen the problem, contrary to anecdotal claims to the contrary.
Airsickness is also one of the few maladies in which good aerobic conditioning may actually increase susceptibility, probably due to better tone in the parasympathetic nervous system which directs involuntary body functions such as digestion.
Introverts get sick more than extroverts, so thinking about illness may be a factor, too. An excessively rigid personality (Type A) may be more susceptible as are people with increased anxiety, fear and insecurity, especially worries related to the flight itself. This may be why stiff-upper-lipped British pilot/author Neil Williams, in his book Aerobatics, said with regard to airsickness, the biggest problem lies in the mind.
Fortunately, motion sickness can be unlearned and conquered. Although as many as 17 percent of military pilots experience motion sickness severe enough to interfere with aircraft control, only 1 percent wash out due to air sickness.
The simplest and best treatment for air sickness is accustomization. Early morning flying with cool, calm air in progressively longer stints is the best approach. Also, the person who is being desensitized needs to feel secure about being in control of how long the flight will last and should have the ability to end it at any time. This isnt the time to say just a little longer now.
For aerobatic neophytes, building up to high-G maneuvers in an orderly fashion on shorter flights rather than starting out with eyeball squishers may work best. As you become more tolerant, extend both flight time and G levels. Good ventilation in the cabin also helps, as does flying in cooler weather.
If accustomization doesnt work or isnt practical, drugs are an option. The military uses two different combinations and I have found both to be moderately effective. Promethazine hydrochloride (Phenergan ) 25-50 mg combined with ephedrine 25-50 mg (Sudafed ) is the easiest to use.
Dextroamphetamine 5 mg and scopolamine .5 mg is the other choice, although it might be harder to talk your family doctor into prescribing these, since dextroamphetamine is a frequently abused drug. These combinations are taken one hour before flight to prevent air sickness and to allow for desensitization.
Other drugs that have been used for air sickness include anti-nausea agents such as Prochlorperazine (Compazine ), dimenhydrinate (Dramamine ) and several agents used for the side effects of chemotherapy. Compazine and Phenergan both come in rectal suppositories and if the airsick passenger is hurting enough, their pants may come down in a hurry. Of course, the practical solution is to plan ahead and take oral tablets before the flight.
One over-the-counter drug which has no systemic effect and is therefore okay in the FAAs eyes is phosphorated carbohydrates or Emetrol, a sweet carbohydrate syrup. Its a formula based on the traditional use of Coke syrup as a nausea treatment in the days when soda fountains actually mixed soft drinks at the counter. The dose is one teaspoon per hour, as necessary.
Other over-the-counter remedies include dramamine, Marezine and Bonine. These are very weak antihistamines and work through sedation, if they work at all which, in my experience, is unlikely. In any case, theyre a gray area as far as legalities for PIC are concerned.
One effective drug which has recently returned to the market is the scopolamine patch (Transderm Scop). The patch looks like a spot bandage and is generally worn behind the ear. The medicine delivery system, which was developed for lengthy travel such as cruises, is absorbed through the skin.
It should be placed on the skin eight hours before the flight (the night before) and can be worn up to three days. It cannot be removed and reapplied. The side effect of scopolamine can be mild sedation and mild dilatation of the pupils which can affect near vision as well as force the user to wear sunglasses.
As with all medications to be used in flight, it ought to be used on the ground for a practice session to insure that no adverse reactions occur. Its also important to check with your physician if you have ongoing medical problems or take other medications. There could be interactions.
There are many non-traditional remedies for air sickness. One I heard about recently was discussed on CompuServes Avsig forum. Several instructors gave testimonials to the use of a bagel eaten just prior to the flight as a sure-fire remedy.
Theres actually some medical basis for this, since a bagel would be similar to Emetrol, a carbohydrate. One of the problems with non-traditional approaches, of course, is that there are few controlled studies and the placebo effect may very well be as effective as the actual remedy itself. In that regard, dramamine and Bonine may actually have some beneficial effect.
Other non-prescription techniques utilize ginger powder (from the grocery store) loaded into gelatin capsules and taken before flight. Ginger is a natural anti-emetic. Acupuncture is another unconventional treatment and, anecdotally at least, is more effective than the acupressure bands which are sometimes sold in pilot stores and catalogs.
Biofeedback has been used successfully by the military but requires time and expensive equipment. Basically, the pilot or passenger is placed in a spin chair after being connected to the biofeedback sensors.
Theyre then spun into illness while attempting biofeedback techniques to stay warm and dry instead of cold and clammy. One Air Force study placed pilots in biofeedback two hours a day for two weeks and returned 79 percent back to flying duties.
Marijuana is a proven effective treatment for air sickness but because of certain logistical difficulties-not to mention legal ramifications-it may be fun but hardly practical.
Ive saved the most effective treatment I know of for last. The ReliefBand is an afferent electric nerve simulator which is worn on the wrist like a watch with the devices electrode over the median nerve. This is the same spot where acupressure bands are worn and where acupuncture needles for nausea and vomiting are placed.
The ReliefBand stimulates the nerve and works with the most predictable success of any other method or drug I have seen. I have prescribed the ReliefBand for chemotherapy patients, pregnant patients and have an ongoing study on pilots in an air combat program flying T-34s in Texas. The device has been very effective in all of these settings. In fact, I know of few instances in which it hasnt worked.
This device was originally introduced as prescription only and was difficult to use and, at $260, expensive. The company which made ReliefBand was sold and the unit was removed from the market.
A replacement is due in August or perhaps a little later from Woodside Biomedical, Inc. (888-668-6648). The company is applying to FDA to make it an over-the-counter device which will come in two models. One will be disposable for use on short trips and the other will be a simpler-to-use permanent unit that will be about one half the original units cost.
The considerable advantage to the ReliefBand is the lack of any side effects, which makes it safe-and legal-for use by pilots and passengers alike. The only contraindications are in people with implanted pacemakers or defibrillation units.
If the revised ReliefBand works as well as the older product-and I have no reason to believe it wont-carrying one of the inexpensive disposable models in the airplane may be the best all-around solution.
by Brent Blue
Brent Blue is a Senior Aviation Medical Examiner who lives in Jackson Hole, Wyoming. He has a Cessna 340 and flies an open cockpit Flaglor HighTow biplane for fun.