From the Griffin Accident Database......
UK Helicopter Fatal Accident Causes+/-
Fatal Accidents [By First Event]
Loss Of Control IMC (25.00%) 10
Spatial Disorientation (10.00%) 4
Other Weather (7.50%) 3
42.50 % of UK Helicopter Fatal Crashes are due to the the three causes listed above.
Any need for improvement in those numbers?
From the IHST 2009 report....a long quote but worth reading. bold print is my doing.
There were 174 U.S.-registered helicopter accidents in 2001, which worked out to 8.0 per 100,000 flight hours. The good news: “This is a decrease of 12.1 percent over the CY2000 accident rate of 9.1 per 100,000 flight hours,” the report states. The bad news: In those accidents, 137 helicopters were “substantially damaged.” That’s 79 percent of the total 174. “Of the remaining, 32 (18 percent) were destroyed, one (0.6 percent) had minor damage and four (2.3 percent) had no damage reported,” it continues.
Only 14 (4 percent) of the helicopters in U.S. 2001 accidents were twin turbines. In contrast, 84 (48 percent) were single-engine turbines and 76 (44 percent) were single-piston helicopters. The majority of CY2001 accidents occurred during personal/private flying, 38 missions (22 percent) and instructional/training, 29 missions (17 percent). The landing phase accounted for 45 (26 percent) of the accidents, hover 30 (17 percent) and maneuvering 29. There was a direct correlation between a higher percentage of accidents and lesser amounts of flying experience in the specific make/model involved in a crash. “For example, the group with the most accidents, personal/private, also has very low median time in rotorcraft,” the report states.
As for casualties: 91 (52 percent) of the CY2001 accidents didn’t result in injuries. “There were 38 accidents (22 percent) with minor injuries, 17 (10 percent) with serious injuries, and 28 accidents (16 percent) that resulted in fatal injuries,” the report continues. The bottom line: of the 174 accident helicopters, there were a total of 373 people on board at the time of the accident with a total of 48 fatalities, or 12.9 percent. Reviewing the statistics, HAI’s Zuccaro noted that “66–75 percent” of the accidents that occurred in 2001 were caused by “human factors.” But he was quick to point out that human factors are not a synonym for ‘pilot error’. Although that is a part of the mix, other elements such as pilot workload, aircraft design, inadequate training for the missions required and technological shortfalls were also to blame.
“We’re not pointing our fingers at pilots,” he said. “They’re just one factor.” In particular, Zuccaro said that many aircraft feature designs that require pilots to do too much. He also chastised managers who send their pilots on night missions without proper tools such as night vision goggles. Still, of the various Standard Problem Statements (SPS) the U.S. JHSAT used to classify accident causes in its CY2001 report, “The SPS, pilot judgment and actions, dominated the problems, appearing in over 80 percent of the accidents analyzed.”