April 1993 Volume 36 / Number 4
The year that was
If you wanted to describe the typical accident in general aviation in 1992, it might go something like this: A private pilot flying a fixed-gear single-engine aircraft bounced hard on the runway and then lost directional control as the aircraft either porpoised or drifted off to one side of the runway. Damage to the aircraft was substantial, but the pilot and passenger escaped serious injury.
The AOPA Air Safety Foundation has completed the 1992 Joseph T. Nall Report, named after the late National Transportation Safety Board member who was a strong supporter of general aviation. The report, done annually, sum marizes the accident history for the year, and for the, record, 1992 was not much different than 1991. People frequently ask, "What's the trend?" In truth, there isn't much change on a year-to- year basis. You can pretty well predict how certain classes of aircraft and pilots, will fare in the accident tallies in almost any year.
The overall accident trend continues slightly downward, with the accident rate at 7.19 per 100,000 flight hours. The fatal accident rate was 1.50 per 100,000 hours and has remained essentially flat over the past four years. On average, one accident in five is fatal, but in one category, the outcome is sadly predictable. Weather-related accidents continue to be the leading killer, with two out of three being a pilot's final flight; 12.4 percent of all pilot-related accidents involved a weather encounter.
As usual, pilots are clearly the leading suspected cause of accidents in 1992. Note that we can't say "probable cause" yet because the data that is used to develop the report is preliminary and subject to change as accident investigators file their final reports. So far, pilots are identified as the culprit in about 64 percent of the accidents. Mechanical problems are indicated in about 10 percent, and the unknown category makes up the balance. if the year follows tradition, as the unknowns are more fully investigated, pilot error will wind up around the 80- to 85-percent level, once again indicating that we are our own worst enemies.
Looking at aircraft class, we find some distinct tendencies. Fixed-gear singles have lots of takeoff and landing accidents, accounting for about 49 percent of the overall rate in the class. This isn't too surprising because many of these aircraft tend to be flown by lower time pilots who, in some cases, haven't developed or maintained the basic skills. The overwhelming cause, however, (31 percent) for serious accidents in this group is trouble encountered during maneuvering flight. This category includes stalls out of low turns, buzzing, and collisions with wires, towers, and other objects. That is a skill set I don't believe enough instructors cover during primary training, and apparently, some new pilots believe low and slow is the way to go. For longevity, you might want to consider the opposite tack. About 5.5 percent of the fixed-gear singles had weather-related accidents, but this accounted for about 23.5 percent of the class fatalities.
In the single-engine retractable group, tangling with weather during cruise flight was clearly lethal. Almost 21 percent of the serious accidents in the class resulted in 30 percent of the fatalities in 1992.
Multiengine aircraft had 47 percent of their serious accidents in the weather category, which resulted in 44 percent of the fatalities. Pilot error during the approach phase added another 18 percent to the serious accident tally.
Another category that is gaining distinction is the homebuilt aircraft. Many of these aircraft have the characteristics of reduced drag, large engines, and high wing loading. This results in eye-opening performance, but there are some definite tradeoffs. Higher stall speeds and, in some cases, lower stability bring maneuvering (27 percent) and takeoff (20 percent) accidents into prominence for serious or fatal injuries. The message is clearly that if you're going to fly this type of equipment, get the training and recent experience to do the job safely. One positive note is that mechanical problems with homebuilts approximate the rest of the single-engine fleet. There were two structural failures, but we don't know yet if these were caused by a pilot-induced load or an actual fault in the aircraft structure.
Happily, alcohol and drugs are a non-factor this year as in all years in recent history. The preliminary results show less than a half-percent involvement, and at this writing, there were only five fatalities, so it appears that education has all but erased this problem.
Data are still being collected on midair collisions, but so far, it appears there were 10 in 1992.
Weather-related accidents took a significant toll from all aircraft categories. The majority of these involved continued VFR into instrument meteorological conditions. The ASF will be treating this topic in much greater detail in the future. For now, our lesson should be to approach weather warily, particularly in mountainous areas, and if you're not instrument rated and on an IFR flight plan, treat clouds as if they were filled with chlorine gas. This is the riskiest kind of flight.
A free copy of the Nall Report is available by sending a large self-addressed, stamped envelope to the AOPA Air Safety Foundation, Attention: Nall Report, 421 Aviation Way, Frederick, Maryland 21701.
See also the index of "Safety Pilot" articles, organized by subject. Bruce Landsberg is executive director of the AOPA Air Safety Foundation.