helicopter

Helicopters have a bad reputation. Many people unfamiliar with them think that helicopters are a collection of rotating parts, ready to fly apart and cause disaster at any time. Or they have seen a tail rotor shot off by a missile in an action movie and picture themselves spiraling to the ground, victims of inherent instability. People have had to make judgements about the riskiness of helicopter flight without good information, not because data about helicopter safety doesn’t exist, but because it had never been organized to give a clear picture of the risks of helicopter flight. At NASA Ames Research Center we undertook to develop such an organization of the data from over one thousand helicopter accidents investigated by the NTSB. [See information below on the study report.]
We began by asking what is the risk of a helicopter accident, and how does that risk compare to risk associated with other modes of travel. When we compared helicopters to airliners, we found that airliners have an accident rate (per departure) about one tenth that of helicopters, no surprise there. We were somewhat surprised that about 10% of accidents involve fatalities for both airliners and helicopters. This means that fatal accidents are about ten times more likely for helicopters, because accidents generally are about ten times more likely, but the accidents themselves are neither more nor less fatal.
Of course, airliners and helicopters are apples and oranges, differing in size, speed, flight environment and pilot population. General aviation aircraft as a group are much more similar to helicopters, minus the rotating parts. And their accident rate is more similar too. In fact the accident rate (per hour) for helicopters and general aviation is nearly identical, about eight accidents per 100,000 hours. Again about one tenth of accidents involve fatalities.
So maybe smaller vehicles are just more dangerous. Then what about cars? They are small. And we all know that the most