Pilots use risk management as described in earlier chapters to analyze the likelihood and potential severity of an incident or accident based on identified hazards. The process takes time, thought, and collection of information pertinent to the flight. However, once a planned operation begins, a pilot may encounter unforeseen hazards or threats. In addition, a pilot may respond inappropriately to a given condition, thus making an error. This chapter provides strategies pilots may use once flight begins.

Threats have the following characteristics:

Some common threats include:

Errors are deviations from intended or expected actions and result in a reduction in safety margins. They include both unintentional and intentional acts. They do not require the presence of a threat and can occur spontaneously. Errors may cause confusion and increase workload.

Errors may result from insufficient training and experience, inadequate flight planning or preparation, external pressures, and physiological and psychological effects.

A pilot who lacks training or experience regarding a given set of conditions may not be in a position to respond appropriately to a related sequence of events and the potential for an inappropriate decision or error increases. Organizations often provide training and supervised operating experience for this reason. General aviation pilots who are enthusiastic about meeting new challenges may find themselves in an unfamiliar situation that may result in serious errors. Pilots seeking the thrill of an adventure should consider the potential danger from errors that may occur.

Chapters 3, 4, and 5 of this handbook discuss risk analysis as an important step in the flight planning process. However, the pilot can only conduct a preflight risk analysis based on the information gathered before flight. Inadequate flight planning may leave a pilot in unanticipated conditions and can lead to errors. For example, a pilot dropped off a passenger at the Edward F. Knapp State airport (KMPV) in rural Vermont and expected to refuel for the return trip to White Plains, New York (KHPN). Upon arrival, fuel or other services were not available since it was the weekend. The pilot thought about waiting but decided to fly home after estimating the fuel would be sufficient. The pilot filed a flight plan in the air as visibility started to diminish after departure. Soon after, ATC required a hold as the destination airport had closed for snow removal. The entire region was becoming affected by a snowstorm, and the pilot was running low on fuel. Luckily, after explaining the situation to the controller, the pilot was able to divert to Bridgeport in Connecticut (KBDR), which was the last airport open in the area. Fortunately, the ceiling was just above minimums for the instrument approach, and the pilot was able to land the aircraft in a few inches of snow. Bridgeport closed shortly thereafter for snow removal.

Some of the items listed on the I’m Safe checklist (illness, medication, stress, alcohol, fatigue) have the potential to cause pilot errors. For example, it may become difficult or impossible for a stressed or fatigued pilot to focus on a situation or task. Not acting when necessary also constitutes an error.

Limitations affect human senses and perception. For example, when will a pilot see another aircraft on a collision course? The avoidance maneuver may depend not only on where the pilot is looking, but also on the pilot’s individual sense of vision combined with all the visual signals received at the same time.

Psychological effects include stress, emotion, expectation bias, and the effects of personality.