Pilots who start flying earlier in life, and have a higher level of training, are at lower risk of being involved in a weather-related general aviation (GA) accident then those who begin flying when they are older.
In fact, the age at which a pilot commences flying is a better predictor of future accident involvement than age at the time of flight, according to a new National Transportation Safety Board (NTSB) study. In effect, the study concluded that pilots with higher levels of training and experience, gained by an earlier involvement in aviation, are less likely to be involved in a weather-related accident. The study breaks new ground by looking at fatal weather-related accidents and comparing the circumstances to a control group flying in the same vicinity and time who did not have an accident. This comparison included interviews with the control group pilots (the ones in the accident aircraft were killed), and covered the type of aircraft, the training and other circumstances, to better understand the factors contributing to these accidents.
Rather than looking at common factors in accidents, the new study compares accidents to non-accident flights to determine characteristics that set accidents apart and contributed to their occurrence.
The study was hailed by the Aircraft Owners and Pilots Association (AOPA) for reaffirming that pilots with higher levels of training and experience are less likely to be involved in a weather-related fatal accident. Bruce Landsberg, executive director of the AOPA Air Safety Foundation, said, “The NTSB study does an excellent job of comparing ‘apples to apples’ and ‘oranges to oranges,’ and provides more statistical support for the importance of continued training.”
The study does more than that. The finding that pilots who start flying at a younger age are at less risk of a weather-related accident may be counter-intuitive. However, the NTSB found that those pilots generally attain higher levels of licensing (e.g., commercial or transport category ratings) and have gone into flying in some way as a profession. The pilots at greatest risk are those who achieve professional success in some other area, buy their own airplane later in life, and are engaged in personal flying.
Of particular concern to the NTSB is the fact that a GA pilot can fail every knowledge question regarding weather and yet still pass the qualification test. Twelve of 60 questions deal with weather, and a pilot can incorrectly answer all of them and yet still achieve a passing score on the test. The NTSB believes a minimum level of performance in each test category should be achieved, on the grounds that aviation requires multiple skills and a minimum knowledge in each area is requisite.
As Dr. Vernon Ellingstad of the NTSB professional staff recounted, “We’re not here to indict older pilots, but to identify risk factors that can be guarded against in their training.”
Of all aviation accidents, about 90 percent involve GA, and of these, about 10 percent involve inclement weather. Inclement weather is here defined as instrument meteorological conditions (IMC) or marginal visual conditions. More to the point, weather is a remarkable constant in GA accidents, averaging about 5-10 percent of all accidents per year. This seemingly small percentage constitutes a quarter of all GA fatalities. Therefore, if weather related accidents could be reduced, the effect would be great on the overall GA fatal accident rate.
The latest NTSB study of GA accidents (there have been a number over the years) identified 72 accidents that killed 108 pilots and passengers over a nine-month period in marginal weather during the period August 2003 to April 2004. These were compared to a control group of 135 flights. These matching non-accident flights were flown within 30 miles and 30 minutes of the accident flight, and were further selected based on weather conditions, the rules of the flight (e.g., IMC), the number of engines and their type (e.g., piston, turboprop, jet), previous pilot accidents, incidents and violations, and qualification scores on tests, as well as other factors, such as whether the pilot was instrument- rated, whether he or she owned or was renting the aircraft, the planned flight length, and the type of weather briefing received prior to takeoff.
Pilots of the non-accident flights were all interviewed within 72 hours of their flights.
To summarize from the study:
- The NTSB found that non-accident pilots started flying at a younger age, mostly before age 25, and that risk increases 3.5-4.8 times for other pilots. The difference is not likely the result of age-related effects, but the fact that those who enter aviation earlier are more likely to achieve commercial certification, and career pilots are subject to more training and oversight.
- A higher proportion of accident pilots were non-instrument-rated private pilots.
- Three out of four of the accident pilots were flying their own airplane.
- The NTSB developed a cumulative pass rate for private, commercial and instrument tests, dividing pilots into those with high pass rates (70 percent or better) and those with low pass rates (under 70 percent). It found that pilots with a history of low pass rates were more likely to be involved in an accident. For example, the pilot involved in the Air Sunshine ditching failed nine practical tests over a 15-year period (see ASW, Oct. 18, 2004). “You can retake the test” until you pass it, noted the NTSB’s Dr. Jana Price. She pointed out that applicants who miss all the weather questions may still pass the test, and that the absence of a minimum standard is a deficiency.
- Nineteen percent of accident pilots were involved at some time in a mishap, compared to 10 percent of the control group.
- An average of one in 330 active pilots are annually involved in an accident. Most survive and continue to fly, but with a 3.1 times greater risk of another accident. As the NTSB study noted, “Existing records could be used to identify pilots at heightened risk.”
- It is estimated that 66 percent of the fatal accident pilots had a preflight weather briefing, but that more than 90 percent of control group pilots had such a briefing. Moreover, 57 percent of non-accident pilots used more than one source – the FAA’s flight service station (FSS) briefings- choosing to supplement that basic weather briefing with graphical images and other interactive tools available on the Internet.
As a result of these findings, the NTSB issued a number of recommendations. In addition to establishing a minimum number of weather-related questions that must be answered correctly, the NTSB recommended that pilots routinely consult alternative sources of weather information that is currently not available from a standard weather briefing. For example, the National Weather Service‘s Aviation Weather Center (AWC) pages on the Internet contains a range of graphical displays, but they appear under this caveat:
“The AWC Homepage ‘Standard Briefing’ is intended as a tool to help pilots better visualize weather and weather-related hazards. It is not intended as a substitute for a weather briefing obtained from a Flight Service Station (1-800-WXBRIEF).”
The NTSB believes some of those graphical displays are exceedingly useful and should be part of the FAA’s authorized pre-flight weather services, especially since the FAA has announced that it’s transitioning to a new FSS operation in late 2005.