A minor illness such as a cold, or a major illness or injury interferes with the normal rate of learning. This is especially important for flight instruction. Most illnesses adversely affect the acuteness of vision, hearing, and feeling, all of which are essential to correct performance.

Airsickness can be a great deterrent to flight instruction. A learner who is airsick or bothered with incipient airsickness is incapable of learning at a normal rate. There is no sure cure for airsickness, but resistance or immunity usually can be developed in a relatively short period of time. An instructional flight should be terminated as soon as incipient sickness is experienced. As the learner develops immunity, flights can be increased in length until normal flight periods are practicable.

Keeping learners interested and occupied during flight is a deterrent to airsickness. They are much less apt to become airsick while operating the controls themselves. Blowing fresh air across the face also helps reduce symptoms of incipient sickness. Rough air and unexpected abrupt maneuvers tend to increase the chances of airsickness. Tension and apprehension contribute to airsickness and should be avoided.

Fatigue is one of the most treacherous hazards to flight safety as it may not be apparent to a pilot until serious errors are made. Fatigue can be either acute (short-term) or chronic (long-term). Acute fatigue, a normal occurrence of everyday living, is the tiredness felt after long periods of physical and mental strain, including strenuous muscular effort, immobility, heavy mental workload, strong emotional pressure, monotony, or lack of sleep.

Acute fatigue caused by training operations may be physical or mental, or both. It is not necessarily a function of physical strength or mental acuity. The amount of training any learner can absorb without incurring debilitating fatigue varies. Generally speaking, complex operations tend to induce fatigue more rapidly than simpler procedures do, regardless of the physical effort involved. Fatigue is the primary consideration in determining the length and frequency of flight instruction periods and flight instruction should be continued only as long as the learner is alert, receptive to instruction, and is performing at a level consistent with experience.

It is important for a flight instructor to be able to detect fatigue, both in assessing a learner’s substandard performance early in a lesson, and also in recognizing the deterioration of performance. If fatigue occurs as a result of application to a learning task, the learner should be given a break in instruction and practice.

A flight instructor who is familiar with the signs indicative to acute fatigue will be more aware if the learner is experiencing them. The deficiencies listed below are apparent to others before the individual notices any physical signs of fatigue.

Acute fatigue is characterized by:

Another form of fatigue is chronic fatigue which occurs when there is not enough time for a full recovery from repeated episodes of acute fatigue. Chronic fatigue’s underlying cause is generally not “rest-related” and may have deeper points of origin. Therefore, rest alone may not resolve chronic fatigue.

Chronic fatigue is a combination of both physiological problems and psychological issues. Psychological problems such as financial, home life, or job-related stresses cause a lack of qualified rest that is only solved by mitigating the underlying problems before the fatigue is solved. Without resolution, human performance continues to deteriorate, and judgment becomes impaired so that unwarranted risks may be taken. Recovery from chronic fatigue requires a prolonged and deliberate solution. In either case, unless adequate precautions are taken, personal performance could be impaired and adversely affect pilot judgment and decision-making.

Dehydration is the term given to a critical loss of water from the body. Dehydration reduces a pilot’s level of alertness, producing a subsequent slowing of decision-making processes or even the inability to control the aircraft. The first noticeable effect of dehydration is fatigue, which in turn makes top physical and mental performance difficult, if not impossible. Flying for long periods in hot summer temperatures or at high altitudes increases susceptibility to dehydration. High altitude is an issue since dry air at high altitudes tends to increase the rate of water loss from the body. If this fluid is not replaced, fatigue progresses to dizziness, weakness, nausea, tingling of hands and feet, abdominal cramps, and extreme thirst.

Heatstroke is a condition caused by any inability of the body to control its temperature. Onset of this condition may be recognized by the symptoms of dehydration, but its recognition may occur too late if it results in a sudden complete collapse. To prevent these symptoms, it is recommended that an ample supply of water be carried and used at frequent intervals on any long flight, whether the pilot is thirsty or not. If the airplane has a canopy or roof window, wearing light-colored, porous clothing and a hat helps provide protection from the sun. Keeping the flight deck well ventilated aids in dissipating excess heat.

Learners can become apathetic when they recognize that the instructor has made inadequate preparations for the instruction being given, or when the instruction appears to be deficient, contradictory, or insincere. To hold the learner’s interest and to maintain the motivation necessary for efficient learning, instructors should provide well-planned, appropriate, and accurate instruction. Nothing destroys a learner’s interest as quickly as a poorly organized period of instruction. Even an inexperienced learner realizes immediately when the instructor has failed to prepare a lesson. [Figure 2-7]

Instruction may be overly explicit and complicated, too elementary, or so general that it fails to evoke the interest necessary for effective learning. To be effective, the instructor teaches for the level of the learner. The presentation should be adjusted to be meaningful to the person for whom it is intended. For example, instruction in the preflight inspection of an aircraft should be presented quite differently for a learner who is a skilled aircraft maintenance technician (AMT) compared to the instruction on the same operation for a learner with no previous aeronautical experience. The instruction needed in each case is the same but a presentation meaningful to one of these learners might not be appropriate for the other.

Poor instructional presentations may result not only from poor preparation, but also from distracting mannerisms, personal untidiness, or the appearance of irritation with the learner. Creating the impression of talking down to the learner is one of the fastest ways for an instructor to lose learner confidence and attention. Once the instructor loses learner confidence, it is difficult to regain, and the learning rate is unnecessarily diminished.