Washington (CNN) -- Federal safety investigators Thursday launched a study of home-built aircraft to see if there are ways to drive down accident rates.
The Experimental Aircraft Association touts a low fatal accident rate among experimental-amateur-built, or E-AB, aircraft. But the National Transportation Safety Board says the planes account for a disproportionate share of fatal accidents among general aviation aircraft.
One of the most notable was in 1997, when singer-songwriter John Denver died when his amateur-built Long-EZ aircraft crashed in Pacific Grove, California. The NTSB concluded Denver inadvertently hit his right rudder while turning in his seat to reach an unmarked fuel selector handle behind him. The builder's decision to place the handle in a hard-to-access position and Denver's inadequate training on the plane contributed to the accident, it said.
According to the NTSB, home-built aircraft represent about 8% of the general aviation fleet and 4% of the flight hours, but they account for about 18% of fatal general aviation accidents. Last year there were 67 fatal accidents involving amateur-built aircraft, according to the industry.
And the number of home-built aircraft is growing. About 33,000 of the 224,000 general aviation aircraft in the United States are classified as E-AB, the NTSB said.
As part of the board's study, the Experimental Aircraft Association will host a web-based survey for home-built aircraft owners and will share the results with the NTSB.
The study will look at a range of issues, including transition training for pilot-builders of experimental aircraft, flight test and certification requirements, maintenance, and system failures.
"Earlier studies have looked at isolated E-AB safety issues, but this is the first study to comprehensively examine both the building and piloting of these unique aircraft," said Joseph Kolly, director of the NTSB Office of Research and Engineering. "And the direct input from E-AB owners and others involved in the design and day-to-day operations of these aircraft will be of enormous value in understanding all of the aspects that play a role in the safety of experimental flight operations."
The completed safety study is expected to be published by the fall of 2012.