From what I have seen, read and heard, the major reason why IMO the US seems to have more accidents than the JAA countries is that a larger percentage of what we do with helicopters is deeper within the 'Money' Curve, aka HV Curve. I haven't seen any heli-logging or rappelling in Europe, except the rappelling done by police or special ops people.
As for the age old question of a twin being safer than a single. The accident records here in the US, show almost no difference between twin and single. If an actual engine failure does occur in a turbine engine it is usually fuel related. If it is a mechanical failure (quite rare, considering the number of hours flown) with the engines side by side in most installations, parts quite often end up in the 'good' engine. As for the containment ring, all that seems to do is ensure that the parts go into the good engine, not through it. I can say that I speak with some experience. In my flying career I have had 9 engine failure events. Surprisingly, only four were in piston engines. One was caused by a system failure that filled the oil tank with avgas and burned out the engine. It was traced to an AD note that wasn't complied with. Another was caused by a shop that didn't overhaul a fuel control unit that they claimed they did and the engine flooded out. The other two were caused by cylinder failures. Which is always a weak point in turbocharged engines. Two of the turbine engines had T wheels come apart due to improper overhaul (by the outside vendor). One was caused by an oil pump failure and another was a FCU failure. And the last, was a FOD failure. These were ALL multi engine aircraft. IMO the more engines you add the more your risk of an engine failure increases exponentially. Further more, except for the piston fuel control unit failure, which happened in cruise flight, all happened on takeoff. From what information I have gotten, a majority of actual engine failures happen right after a major power change and most often when the power has been increased.
The engines feed from the same fuel tank, so any fuel issues, lack of or contamination will affect both engines. And the engines are connected to the same transmissions, with a few exceptions. Many of the mechanical failures over here are not engine issues, but component issues like transmissions.
On top of that many twins have a minimum single engine speed, which would make landing on a hospital heliport difficult if not impossible. Personally, I feel just as safe in a single engine helicopter as I do in a twin. As for a single engine airplane, that really depends.
Last edited by rick1128; 28th Jun 2010 at 14:06.