Aerospace medicine is the field of medical science concerned with the effects of flight on human health. It deals with aviation medicine, the care of airplane crews and passengers; and space medicine, the care of astronauts. Doctors and scientists in this field try to increase the job performance and safety, as well as the health, of people who fly.
Aviation medicine.
There are many common stresses of air travel. They include motion sickness, noise, vibration, changes in oxygen levels, and rapid changes in speed and atmospheric pressure.
An important stress in fighter aircraft is a rapid upward acceleration. This movement can cause blood to be pooled, or concentrated, in the lower parts of the body. The flow of blood to the heart may then be insufficient for the heart to maintain adequate circulation to the brain, causing unconsciousness. As a result, fighter pilots must wear special trousers called G suits that squeeze blood out of the legs and back to the heart.
Doctors who specialize in aviation medicine are called flight surgeons. Flight surgeons help to design equipment and develop crew selection and training programs. Other areas of aviation medicine include investigating accidents, training crews for survival after crashing, and transporting sick or injured people by air.
Space medicine.
During space travel, weightlessness (freedom from the pull of gravity) can cause several disorders. These include motion sickness, disorientation (loss of a sense of direction), and a shift of blood and other fluids from the feet and legs to the chest and head. Weightlessness also can cause the loss of bone and muscle tissue in the feet and legs. This condition probably occurs because the bones and muscles no longer need to work against the pull of gravity. Researchers are seeking a combination of exercises, drugs, and special diets that will reduce bone and muscle loss.
Another hazard of space flight is radiation from the sun and other objects in space. Being exposed to radiation increases a person’s chances of developing leukemia and other cancers. Astronauts exposed to more than a certain amount of radiation would be grounded. Today’s spacecraft have too little protection against radiation for long-duration manned flights into deep space (space beyond the earth and the moon).
Some scientists have suggested that the most serious problem for astronauts on long missions could be psychological. Space travelers have found that after 30 days of being confined together in a small space on a flight scheduled to last many months, they develop an intense dislike for each other and a strong desire to go home.
