content_image/577293.jpg content_image/577294.jpg
<img src='content_image/577293.jpg'>

The third point at which to review the 5 Ps is the midpoint of the flight.  [Figure 6-14]  Pilots often wait until the ATIS is in range to check weather, yet at this point in the flight many good options have already been passed. Additionally, fatigue and low altitude hypoxia serve to rob the pilot of much of his or her energy by the end of a long and tiring flight day. Fatigue affects memory, attention to detail, and communication ability. Frequently associated with pilot error, it also impairs coordination and degrades situational awareness, seriously influencing a pilot’s ability to make effective decisions. There are several types fatigue. Physical fatigue results from sleep loss, exercise, or physical work while factors such as stress and prolonged performance of cognitive work result in mental fatigue. 

<img src='content_image/577294.jpg'>

Hypoxia or oxygen starvation also robs a pilot of physical and mental acuity. Oxygen deprivation is insidious because it sneaks up on the unwary and steals the first line of sensory protection, the sense that something is wrong. The human body does not give reliable signals at the onset of hypoxia so a pilot needs special training in how to recognize the symptoms. This training is important because the brain is the first part of the body to reflect a diminished oxygen supply and evidence of that is usually a loss of judgment. 

Everyone’s response to hypoxia varies, but the effects of hypoxia can be safely experienced under professional supervision at the Civil Aeromedical Institute’s altitude chamber in Oklahoma City and at 14 cooperating military installations throughout the United States. To attend a 1-day physiological training course, contact the FAA Accident Prevention Specialist for an Aeronautical Center (AC) Form 3150-7. 

Once a pilot begins to suffer a loss of energy, he or she transitions from a decision-making mode to an acceptance mode. If the flight is longer than 2 hours, the 5P check should be conducted hourly. This is also a good time to evaluate the destination airport. Believe it or not many pilots have more problems on the ground taxiing than on the approach. Because larger airports have taxiways designed for large transport aircraft, the vantage point for a 767 crew sitting 18 feet off the ground regarding taxiways (especially at night) is superior to that for a pilot of a Cessna 172 with a vantage point at 6 feet. Therefore, at the midpoint of the flight, the pilot should review the layout, approaches, and the taxiway structure and its identification system. For instance, at Atlanta Hartsfield, a pilot is expected to understand the difference between “inner and outer M” (Mike) taxiway, and at Dulles a pilot is expected to know where “spot two” is located. Landing is not the time to review the airport facility. Conversely, if a pilot does not know the idiosyncrasies of the airport, requesting progressive instructions and/or letting ATC know he or she is “not familiar” reflects professionalism. 

The last two decision points are just prior to descent into the terminal area and just prior to the final approach fix, or if VFR just prior to entering the traffic pattern, as preparations for landing commence. Most pilots execute approaches with the expectation that they will land out of the approach every time. A healthier approach requires the pilot to assume that changing conditions (the 5 Ps) will cause the pilot to divert or execute the missed approach on every approach. This keeps the pilot alert to conditions that may increase risk and threaten the safe conduct of the flight. Diverting from cruise altitude saves fuel, allows unhurried use of the autopilot, and is less reactive in nature. Diverting from the final approach fix, while more difficult, still allows the pilot to plan and coordinate 

