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Source: Flight Instructor’s Safety  Report


Volume 12, No. 1        Another Free Service of the AOPA Air Safety Foundation       January 1986

Editor: Dick Gless, Vice President Operations Contributing Editor: Bob Carter, Director, Flight Instructor Department

Ralph F. Nelson, Executive Vice President





By Russell Lawton, ASF Staff and Richard Clarke and Ludwig Benner,Jr., Events Analysis Inc.



The crew of a commuter flight departed IFR for their final destination of the day only 40 flying minutes away. Shortly after takeoff, the left engine generator failed. The first officer incorrectly identified the failed generator and actually disconnected the right engine generator. Despite repeated attempts, he was unable to restore power to the aircraft's electrical system.

Although darkness had fallen, the crew elected to continue the flight in instrument conditions believing it could be completed with the battery power remaining. Cloud bases in the area were 2,000 feet MSL with tops at 10,000 feet. Visibility below the cloud bases was one mile in rain and there were scattered thunderstorms in the area.

Thirty minutes later (with almost all electrical equipment shut down) the captain asked the first officer to "Watch my altitude, I'm going down to twenty four hundred (feet)." Minutes later, with battery power all but depleted, the captain asked, "Do you have any instruments, do you have a horizon?" Shortly thereafter, the aircraft struck the ground in a descending right turn. There were no survivors.

Every flight forces the pilot to adapt to changes to ensure successful flight completion. An important idea that goes with adapting to change is the concept of "success." Some pilots believe that a flight is successful only if it is completed from the point of departure to the intended destination. On the other hand, seasoned aviators know that a flight is successful as long as it ends safely either at the intended destination or, due to circumstances beyond the pilot's control, somewhere else. No flight can be considered successful if it results in damage to the aircraft or injury to its occupants.

As flight instructors, we must teach our students to assess and cope with the risks associated with flying. Pilots must understand the decisionmaking process in order to adequately assess these risks. The National Transportation Safety Board (NTSB) tells us that 80-85% of all general aviation accidents involve "pilot error." This is another way of stating that errors in the decisionmaking process are involved in a large portion of unsuccessful flights.

By exerting a positive influence on the decision-making process of their students, flight instructors can reduce the number of unsuccessful flights. Much data has been collected and analyzed to give pilots information about unsuccessful flight or accidents. Figure 1 lists the ten most common causes of general aviation accidents according to NTSB.








      Accident Cause


Pilot - Inadequate preflight preparation and/or planning


Pilot  - Failed to obtain/maintain flying speed.


Powerplant - Failure for undetermined reasons


Pilot - Mismanagement of fuel.


Fuel exhaustion.


Material failure.


Pilot - Selected unsuitable terrain.


Pilot - Improper level off.


Pilot - Misjudged distance and speed.


Pilot - VFR into adverse weather conditions



Figure  1


Notice that the majority of these factors involve decision making, reflecting the unsuccessful outcome of the pilot's decision-making process. With this in mind, how can we help pilots use this knowledge to reduce the odds of being involved in accidents stemming from these causes?

The decision-making process which enables pilots to complete flights successfully is a five-step process which can be learned and practiced. The five steps are:


1.     Recognize changes that affect flight outcomes.

2.     Assess the risk(s) involved due to changes.

3.     Decide what action(s) would control the changed risks.

4.     Take action according to the decision(s) reached.

5.     Monitor the effectiveness of the actions.

Traditional flight training provides pilots with the necessary skills to take action once the decisionmaking process reaches step 4, but pilots usually don't receive much training in recognizing problems that may develop, especially the self-induced problems of attitude or those caused by outside circumstances.

The commuter flight at the beginning of this article is a good example. The crew recognized that a generator had failed, but incorrectly diagnosed the problem by misidentifying the failed generator. The risks involved with continuing the flight on battery power under instrument conditions were probably ignored by at least one of the pilots due to an overwhelming desire to return to home base for repairs. Based on this decision, the crew elected to continue instead of returning to the departure airport under VFR conditions or landing at one of six other airports along their route.


In the remainder of this article, we will discuss Step 2 of the decisionmaking process, i.e., risk assessment. In assessing risk, pilots need to have a systematic way of knowing where to look for risk. One of the simplest and most effective ways to think about risk is to consider it as occurring in four distinct aspects of flying. These four areas can be considered the four basic elements of risk in flying:


     The Pilot

     The Aircraft

     The Environment



Each of these basic risk elements applies not only to the flight itself, but also to the "mission" or reason for the flight. For example, some risks such as unexpected icing may be encountered during a flight, but other risks such as the desire to reach home on a Sunday night prior to a big day at work are part of the flight before it ever leaves the ground.

The purpose of showing our students how to develop or improve their decisionmaking skills is to give them a way to manage major and minor risks that occur naturally as part of flying. No flight can be conducted without risk, so decision making is a continuous process of neutralizing that risk. To apply the decisionmaking process, a developing or potential hazard must first be detected, then the four risk elements must be reviewed. The pilot must take action to reduce or eliminate the effect of increased risk and the action must be monitored to be sure it works. At this point, it would be useful to consider what makes up each risk element.



A pilot's performance may be affected in many ways during a flight. The risk raisers that affect pilots are called "stressors." The four types of pilot stressors are:


Physical stress Conditions associated with the environment that affect a pilot's well being, e.g., temperature, humidity, noise, vibration and lack of oxygen.

Physiological stress Pilot physical conditions such as illness, lack of sleep, inadequate meals, etc.

Psychological stress Internal emotional conditions such as perfectionism or stresses such as the need to make decisions, fly, communicate and navigate.

Sociological stress Outside emotional stresses such as marital problems, family illnesses or deaths and job pressures.

Each of these stressors can raise the total risk during any flight. The following is a partial list of items we can recommend to our students to help balance or neutralize pilot risk raisers.

     Learn about stress.

     Assess yourself realistically.

     Approach problem solving in a systematic manner.

     Avoid distractions in flight.

     Keep your flight workload as low as possible.

     In emergency situations, don't rush.

     Keep current in your aircraft.

     Know the limits of your skill and condition.

     Don't accumulate concern over mistakes. Worry about things after you land.

Pilots must not only assess their stress level, but also their ability to conduct a flight feeling adequately prepared and qualified. First in preflight, then in flight, pilots should ask themselves, "Have I had recent practice or instruction that allows me to fly the airplane in a proficient manner to the places I intend to visit; and, does my proficiency meet the requirements of the changing weather, condition of the aircraft, and other factors?" The answer to such a question may be "no", in that case, some other plan of action which is less demanding or uses stronger skills needs to be developed.


This risk element focuses on the aircraft equipment, its condition and its suitability for the "mission" or intended purpose of the flight. If IFR weather is expected, would a single radio, single VOR aircraft without pitot heat be appropriate? The best time to make this assessment is on the ground during preflight planning. During the flight, if VFR weather unexpectedly changes to IFR weather, the same assessment must be made. If, during a preflight assessment of the aircraft and the other three elements, the pilot decides that the flight can proceed then a continuing process of risk assessment should begin.

Another part of the aircraft assessment would be the condition of the aircraft. Do all of the radios work satisfactorily? Does the engine still develop its original horsepower? Will the fuel endurance enable the flight to reach the intended destination with adequate reserve? These and other questions which relate to the aircraft form part of a pilot's assessment of the aircraft. Although many pilots already make such an assessment during preflight planning, few realize that it is part of a risk assessment process.

In flight, the assessment needs to be done continuously since the conditions change with time even if nothing dramatic appears to be happening. For example, no matter what the flight circumstances, fuel is being burned every instant the engine runs. A successful pilot frequently compares the onboard fuel load with the fuel required to bring the plane to a safe landing at the destination or at a diversion airport.


This risk element is wide reaching and includes situations outside the aircraft which might limit, modify or affect the aircraft, the pilot and the time elements. One environmental "risk raiser" which pilots usually consider is the weather. Considering the high involvement of weather in fatal general aviation accidents this definitely deserves attention.

The regulations governing aircraft operations are another less obvious "risk raiser" that should be considered. Pilots must fly safely and legally in compliance with FAR Part 91 and other applicable FARs. Another environmental aspect would be the airports which may be used during the flight. Items such as density altitude, runway length, obstacles, landing aids, etc., must be considered before and during the flight.


Time risks are brought on by other factors, e.g., fuel being consumed, pressure to arrive by a certain time or an advancing front. Time does not stop. This makes it slightly different than the other three risk elements mentioned above.

The passage of time can be easily overlooked as a pilot sits in the cockpit totally involved in a problem and wondering how to cope with a worsening situation. In the case of the commuter accident discussed earlier, battery power was depleted before the crew could accurately assess the amount of time available to power the aircraft's flight instruments. This problem could have been alleviated by returning to the departure airport or landing en route to diagnose the situation.

If time is short or perceived to be short, impulsive and inappropriate actions may result. Time can complicate an already complex situation. It doesn't just add to the overall level of risk, it multiplies it. The less time available or perceived to be available, the greater the negative effect on the pilot.


Within each of the four risk elements, the individual risks which accumulate are called "risk raisers" since they work to raise the level of risk for the flight. In assessing risk, pilots must be aware of the possibilities for risk accumulation so they can determine the need for neutralizing or balancing the risk raisers. Risk can be assessed in a number of ways.

One easy way to evaluate how severe risks are and how they compare to each other is to rate them on a scale; this is similar to the familiar process of rating something "on a scale of I to 10." Since we train pilots in a variety of aviation subjects, they usually have a good sense of why one risk is greater than another. Figure 2 shows a "risk balancing beam" with risk at the right end.

Like any other balance, the farther out the beam the risk is located, the more severe its effect. If the center of the beam were numbered zero and the far end were numbered four, you would have a "scale of 1 to 4." The pilot's task is to detect the risks, rate them in each of the four risk elements, and apply balancing action on the opposite side. This achieves or regains a safe balance of risk during flight.

To illustrate the use of this "balancing" process in risk assessment, let's discuss the situation of a non-instrument rated pilot who encounters deteriorating weather conditions in flight.

A non-instrument rated private pilot and his family are returning from a weekend in New Orleans to their home in Houston, Texas, a route he flies frequently. He prepares for the flight by estimating fuel requirements and calculates that he can fly nonstop at 8,500 feet and still have 45 minutes reserve since the winds aloft are forecast to be light. The flight service station briefer indicates that a weak front will be near Houston, but ceilings are forecast to remain above 2,000 feet with possible isolated afternoon thunderstorms. He expects to be able to see these storms from his relatively high cruising altitude and decides that he will be able to go around any storms encountered en route.

The family departs at 5:00 pm, two hours late due to delay in getting the air.

craft serviced. By 7:30 pm, they are halfway home and notice lightning flashing in the distance illuminating a large area of thunderstorms. It is dark, and the airplane unexpectedly flies through the edges of a few clouds. The pilot resorts to instrument flying momentarily to get back to VFR conditions. The situation is not what he expected. He determines that a trend has established and starts to assess the situation.


The aircraft His aircraft is instrument equipped and everything is fully operational; however, he is a little behind his fuel plan due to dodging clouds. If he descends below the clouds, his fuel plan will change for the worse due to a lower true airspeed and groundspeed.

The environment The weather is worse than forecast. The "weak" front seems to be quite solid and the scattered cumulus have become broken. He cannot legally fly IFR. He doesn't know the current weather ahead and his family is getting anxious.

The pilot He is not instrument rated; his wife is not a pilot and does not enjoy flying. His last flight training was a BFR over one year ago. They need to get home tonight since the children have school tomorrow and he has several appointments to keep.

Time Fuel is becoming a problem. The weather is deteriorating while they move forward at two miles a minute. The risk factor assigned to fuel can increase geometrically as fuel (time) remaining decreases. For example, with two hours remaining, the risk factor might be 1, but with 20 minutes remaining, the risk factor might increase to 3.

The pilot finally starts to rate the risks listed above. On a scale of 0 to 4, he rates the aircraft as a 2 since it's in good condition but limited for the situation he will encounter if he continues. The environment gets a 4 rating due to the lightning, flight through clouds that aren't supposed to be there, darkness and the tense family situation. He rates the pilot a 3 since he is current but not instrument rated. Time gets a 3, on a scale of 1 to 3, since they want to get home this evening and are continuing to fly into deteriorating conditions. With the evaluation complete, he checks the total:

Aircraft 2, + Environment 4, + pilot 3 = a total potential risk of 9 (maximum value 12). When multiplied by the time element 3, total potential risk is raised to 27 (maximum value 36),

Note that the maximum potential risk is 12 and 9 is a fairly high potential value. The pilot feels that the time risk is high, resulting in an effective risk of 27 which is two‑thirds of the maximum value of 36.

Based on the effective risk level, the pilot starts to determine how he can balance his risk. The weather behind him is VFR and there are airports with good facilities where they can spend the night. A retreat to these airports would result in an immediate improvement in his feeling about the environment outside, and the anxiety of his family. A turn to better VFR conditions and a diversion to a VFR airport within 30  minutes flying achieves a large drop in criticality since he has one‑and‑a‑half hours of fuel remaining.

Having detected the problem, assessed the risk and identified balancers, the pilot decides to turn around. A check of the weather confirms that Houston is under an area of severe thunderstorms. The pilot checks the weather at the new destination and compares the time required to his fuel remaining. This is the fifth and final step of the decisionmaking process, i.e., monitoring the revised plan to be certain that it works.


Good pilot decision making depends on an understanding of, and an ability to use, an orderly decision‑making process. We need to convince students that being a good decision maker in aviation does not mean acting hastily based upon "gut" feelings. With an accurate assessment of the risks associated with each of the four risk elements, pilots are best able to arrive at decisions that ensure a successful conclusion to a flight, even if it means not taking off. Success in decision making is measured very simply; the measure is maintaining the pilot, passengers and aircraft in good health and condition no matter the airport at which the takeoff and landing occurs. END