2.A : Aeromedical Factors

To fly pilots must obtain appropriate medical certification. A medical certificate Is issued after a routine medical examination which by administered only by FAA-designated doctors called Aviation Medical Examiners (AME). There is an FAA directory of AMEs that can be consulted to find an AME in the student’s area.

At one time the student pilot certificate included the medical, but this practice ended as of April 2016. (Medical information is covered in more depth in lesson 3-A, Certificates and Documents.) It is often possible to get a medical certificate even with a medical deficiency, called a "special issuance medical". Operating limitations may be imposed, however.

Once any medical is issued it is self-regulating in that the pilot is always responsible for performing medical self-assessments. It is the pilot who determines whether they are fit to fly, or not.

As of May 1, 2017, a new program was instituted called BasicMed which provides a degree of regulatory relief from the previous medical certification process. It allows pilots to operate without an FAA medical certificate, if appropriate. Under BasicMed a pilot will be required to complete a medical education course, undergo a normal non-AME medical examination, and comply with aircraft and operating restrictions.

Someone with a normally disqualifying condition can, at times, receive a Statement of Demonstrated Ability (SODA) if the condition is one for which a SODA is applicable. At the discretion of the Federal Air Surgeon, a Statement of Demonstrated Ability (SODA) may be granted, instead of an Authorization, to a person whose disqualifying condition is static or nonprogressive and who has been found capable of performing airman duties without endangering public safety. A SODA does not expire and authorizes a designated Examiner to issue a medical certificate of a specified class if the Examiner finds that the condition described on the SODA has not adversely changed.

The actual process of getting a student pilot certificate is like any other FAA certificate. You must complete an application through the Integrated Airman Certification and Rating Application (IACRA) website or by paper using FAA form 8710-1 and submit it to a Flight Standards District Office (FSDO), an FAA-designated pilot examiner, an airman certification representative associated with a part 141 flight school, or a certificated flight instructor.

Given that aircraft operate at altitude hypoxia is a serious concern. The word means "reduced oxygen" or "not enough oxygen", and the major concern is getting oxygen to the brain. The brain is particularly vulnerable to reduced oxygen. There are various ways hypoxia can be induced. Possibilities include :

This condition occurs when there is an excessive loss of carbon dioxide from the body. It often happens when the individual is experiencing stress, fright, or pain and the breathing rate is increased. Pilots encountering stressful situations can unconsciously increase their breathing rate. Additionally when flying at high altitudes a pilot may have a tendency to breathe more rapidly thus inducing a state of hyperventilation.

The symptoms can be quite similar to hypoxia, and it is therefore important to correctly identify the condition correctly. Common symptoms are :

Treatment involves restoring the correct concentration of carbon dioxide into the body. This can be done by forcing normal breathing, breathing into a paper bag or talking aloud to overcome hyperventilation. Also, if supplemental oxygen is being used check the equipment to insure the correct flow rate is being provided.

Recovery is usually quite rapid once the breathing rate returns to normal. Since the symptoms are similar to hypoxia, if in doubt treat for hypoxia as it is the more serious of the two conditions.

Problems can occur with the middle ear and sinuses when there is a difference in pressure of the air outside the body versus the pressure of the air inside the body. Normally these small pressure differences are equalized by the eustachian tube (a tube leading from the inside of each ear to the back of the throat on each side). These tubes are normally closed, but open during chewing, yawning, or swallowing to equalize pressure. When these tubes aren’t doing their job pressure can build up and cause pain in the ear and sinus areas. At the extreme this pain can become quite severe.

This condition is not uncommon during flying due to the rapid change in altitude, and therefore pressure, which if the eustachian tube cannot equalize the pressure can cause pain. Excessive pressure in either direction (i.e. overly high pressure inside, or overly high pressure outside) can cause pain. If extreme these conditions can result in a ruptured eardrum.

Treatment depends upon the severity of the situation. If minor just chewing gum or stretching the jaw may help equalize pressure. Also, pinching the nose and blowing can force air into the eustachian tube and force equalization of the pressure. However, a cold, sore throat, or ear infection can make it not possible to equalize the pressure, and these treatments work better in a descent than a climb. If experiencing minor congestion then nose drops or nasal sprays may reduce the chance of blockage.

Sinuses can have similar failures to equalize pressures. They normally equalize pressure through small openings into the nasal passages, but infections can cause these small passages to be blocked resulting in the inability to deal with the pressure changes. Pain can become excessive, cause teeth to hurt, or can even result in a bloody mucus discharge. This sort of sinus block occurs most often during descents.

The only treatment is to slow the change in altitude, or avoid flying if you are experiencing sinus problems.

Orientation is the awareness of the position of the aircraft and of oneself in relation to a specific reference point and disorientation is the lack of that sense of orientation. Spatial disorientation refers to the lack of orientation with respect to the position, attitude, or movement of the airplane in space. The body uses three separate systems to ascertain orientation and movement in space.

All of these signals come together in the brain, and most of the time the three systems all agree thus giving a clear idea of where and how the body is moving. When they don’t agree spatial disorientation can occur.

When flying these systems can generate conflicting information. Each system has ways in which it can generate invalid information.

This is caused by the brain receiving conflicting information about the state of the body. Anxiety and stress can also affect motion sickness. There are a number of common symptoms which include the following :

One of the earlier symptoms of motion sickness is excessive salivation, for some reason. To counter these feelings you can open fresh air vents, focus on objects outside the airplane, and avoid unnecessary head movement. It can also help to take control of the aircraft and fly smooth, straight, and level. For a student this problem generally goes away after a few flight lessons.

Carbon monoxide is a colorless, odorless gas produced by all internal combustion engines. Aircraft heater vents and defrost vents can often provide a pathway for CO to enter the cabin. Carbon monoxide attaches itself to hemoglobin in the blood about 200 times more easily than oxygen. This prevents the hemoglobin from transporting oxygen resulting in hypemic hypoxia. It can take up to 48 hours for all CO to be flushed from the body. The results of CO poisoning is severe enough to result in death. Common effects of CO poisoning include the following :

If a strong odor of exhaust gases is detected assume that CO is present. However, a dangerous amount of CO may be present even in the absence of exhaust odor. If CO is detected immediately turn off the heater, open fresh air vents and windows, use supplemental oxygen if available, and land.

Fatigue is divided into two broad categories, acute fatigue (short term) and chronic fatigue. Either can cause a degradation of attention or concentration, impaired coordination, and a decreased ability to communicate. Fatigue can be caused by sleep loss, exercise, or physical work. Stress and prolonged performance of cognitive work can result in mental fatigue.

This is defined as a critical loss of water from the body. The first effect to be noticed is fatigue, and top physical and mental performance is difficult. Flying for a long time in hot temperatures or at high altitudes increases the chance of dehydration since the dry air at altitude increases the rate of water loss from the body. If the fluid is not replaced fatigue progresses to dizziness, weakness, nausea, tingling of the hands and feet, abdominal cramps, and extreme thirst. These symptoms distract from flying and skills diminish.

To prevent dehydration carry ample water on any flight, wear light colored clothes to reduce heating, and keep the cabin well ventilated.

DON’T drink and fly. Just don’t. Even a hangover can impair skills and the ability to safely conduct a flight. The pilot is more susceptible to disorientation and hypoxia. The FARs mandate a minimum of eight hours from the last drink, and an even better rule of thumb is eight hours and not feeling any lingering effects of the alcohol.

Medications can have a similar effect, and can impair judgment, coordination, and vision. Anything that depresses the nervous system can make a pilot more susceptible to hypoxia. Do not fly while taking any medication unless approved by the FAA.