6. Recognize that the chances of being involved in an  approach accident increase when an emergency or  other activity distracts from usual procedures.  7. Maintain optimum proficiency in landing procedures.  In addition to the sensory illusions due to misleading inputs to  the vestibular system, a pilot may also encounter various visual  illusions during flight. Illusions rank among the most common  factors cited as contributing to fatal aviation accidents.  Sloping cloud formations, an obscured horizon, a dark scene  spread with ground lights and stars, and certain geometric  patterns of ground light can create illusions of not being  aligned correctly with the actual horizon. Various surface  features and atmospheric conditions encountered in landing  can create illusions of being on the wrong approach path.  Landing errors due to these illusions can be prevented by  anticipating them during approaches, inspecting unfamiliar  airports before landing, using electronic glideslope or VASI  systems when available, and maintaining proficiency in  landing procedures.  Motion sickness, or airsickness, is caused by the brain  receiving conflicting messages about the state of the body. A  pilot may experience motion sickness during initial flights, but  it generally goes away within the first few lessons. Anxiety  and stress, which may be experienced at the beginning of  flight training, can contribute to motion sickness. Symptoms  of motion sickness include general discomfort, nausea,  dizziness, paleness, sweating, and vomiting.  It is important to remember that experiencing airsickness is  no reflection on one’s ability as a pilot. If prone to motion  sickness, let the flight instructor know, there are techniques  that can be used to overcome this problem. For example,  avoid lessons in turbulent conditions until becoming more  comfortable in the aircraft or start with shorter flights and  graduate to longer instruction periods. If symptoms of motion  sickness are experienced during a lesson, opening fresh air  vents, focusing on objects outside the airplane, and avoiding  unnecessary head movements may help alleviate some of the  discomfort. Although medications like Dramamine can prevent  airsickness in passengers, they are not recommended while  flying since they can cause drowsiness and other problems.  CO is a colorless and odorless gas produced by all internal  combustion engines. Attaching itself to the hemoglobin in  the blood about 200 times more easily than oxygen, CO  prevents the hemoglobin from carrying oxygen to the cells,  resulting in hypemic hypoxia. The body requires up to 48  hours to dispose of CO. If severe enough, the CO poisoning  Chronic stress can be defined as a level of stress that presents  an intolerable burden, exceeds the ability of an individual  to cope, and causes individual performance to fall sharply.  Unrelenting psychological pressures, such as loneliness,  financial worries, and relationship or work problems can  produce a cumulative level of stress that exceeds a person’s  ability to cope with the situation. When stress reaches these  levels, performance falls off rapidly. Pilots experiencing  this level of stress are not safe and should not exercise their  airman privileges. Pilots who suspect they are suffering from  chronic stress should consult a physician.  Stress falls into two broad categories: acute (short term) and  chronic (long term). Acute stress involves an immediate  threat that is perceived as danger. This is the type of stress that  triggers a “fight or flight” response in an individual, whether  the threat is real or imagined. Normally, a healthy person can  cope with acute stress and prevent stress overload. However,  ongoing acute stress can develop into chronic stress.  Stress is the body’s response to physical and psychological  demands placed upon it. The body’s reaction to stress includes  releasing chemical hormones (such as adrenaline) into the  blood and increasing metabolism to provide more energy  to the muscles. Blood sugar, heart rate, respiration, blood  pressure, and perspiration all increase. The term “stressor”  is used to describe an element that causes an individual to  experience stress. Examples of stressors include physical  stress (noise or vibration), physiological stress (fatigue), and  psychological stress (difficult work or personal situations).  Tobacco smoke also causes CO poisoning. Smoking at  sea level can raise the CO concentration in the blood and  result in physiological effects similar to flying at 8,000 feet.  Besides hypoxia, tobacco causes diseases and physiological  debilitation that can be medically disqualifying for pilots.  can result in death. Aircraft heater vents and defrost vents  may provide CO a passageway into the cabin, particularly if  the engine exhaust system has a leak or is damaged. If a strong  odor of exhaust gases is detected, assume that CO is present.  However, CO may be present in dangerous amounts even  if no exhaust odor is detected. Disposable, inexpensive CO  detectors are widely available. In the presence of CO, these  detectors change color to alert the pilot of the presence of CO.  Some effects of CO poisoning are headache, blurred vision,  dizziness, drowsiness, and/or loss of muscle power. Any time  a pilot smells exhaust odor, or any time these symptoms are  experienced, immediate corrective action should be taken  including turning off the heater, opening fresh air vents and  windows, and using supplemental oxygen, if available.  Stress  Motion Sickness  Carbon Monoxide (CO) Poisoning  17-12 