Nall Report expands to include helicopters, commercial GA

February 17, 2010

The newest edition of general aviation’s most comprehensive annual safety analysis is out, and for the first time, the AOPA Air Safety Foundation’s Joseph T. Nall Report examines helicopters and for-hire GA operations with aircraft weighing 12,500 lbs. or less.

“The AOPA Air Safety Foundation has been telling the story of what went wrong for two decades,” said Bruce Landsberg, president of the foundation. “The challenge is to take a complex subject and distill it into a comprehensible outline of the prior year’s mishaps. Previous issues covered 90 percent of all GA flight activity. This one adds 90 percent of what was left.”

The current Nall Report is based on 2008 accident data—the last year for which enough accident data are available to be statistically valid and give a complete safety picture. It is available online, and hard copies are available by sending an e-mail request.

Commercial operations

The number of accidents on commercial flights in fixed-wing airplanes increased 18 percent from 2007 to 2008, while estimated total flight activity decreased by one-third. However, the overall accident rate remained 28 percent lower than the noncommercial equivalent, and the fatal accident rate was 55 percent less.

The diversity of commercial fixed-wing flight operations reflects that of GA as a whole. Aerial applicators flew just under 29 percent of all commercial fixed-wing time, almost all of it maneuvering with heavy payloads at low altitude. On-demand cargo and air-taxi flights not only play a different role in remote rural areas than in urban centers, but tend to be carried out in very different aircraft. Accident patterns reflect this variety of uses and underlying risks.

Helicopter operations

Non-commercial helicopter accidents have generally decreased since 2002. At 6.76 per 100,000 hours, 2008’s rate was just more than half the 12.69 observed that year; but after seven years of steady declines, the fatal-accident rate jumped to its highest level of the past five years. Accident rates for non-commercial helicopters remain higher than for comparable fixed-wing flights, but the gap is narrowing, and the fatal-accident rates have been similar since 2004.

Amateur-built aircraft

One area of growing concern is the increase in both the number and rate of accidents and fatal accidents involving amateur-built aircraft.

According to this year’s Nall Report, “2008 saw the highest numbers of fatal accidents and individual fatalities in the past decade, and more total accidents than any year except 2007. The 27% lethality rate in these accidents was 10 full percentage points higher than that for accidents in type-certificated airplanes.”

The report also notes that mechanical failures and unaccountable losses of power account for a significantly higher proportion of accident causes among amateur-built aircraft than among factory-built, type-certificated aircraft.

“The Air Safety Foundation is working with the Experimental Aircraft Association to address amateur-built aircraft safety, with the understanding that experimental aircraft will entail higher risk,” said Landsberg. “Builders, pilots, and designers should have reasonable freedom to experiment while members of the public are entitled to their expectation of safety.”

The analysis from the Nall Report helps identify safety trends—good or bad—and training opportunities where the Air Safety Foundation can focus its efforts.

The AOPA Air Safety Foundation was founded in 1950 solely to help GA pilots improve flight safety. Since that time, the GA total accident rate has dropped by more than 90 percent despite a large increase in GA flight hours. The foundation produces live seminars, online interactive courses, videos, written Safety Advisors, and other aviation safety materials for free distribution to all GA pilots.