I love the comment made about how fast the topic of conversation has changed to Singles Vs Twins.....and then you notice that the gap between posts 49 and 50 is.....4 years!!
Meanwhile back at the ranch....Most here are talking from an insiders perspective (obviously!) because we are all passionate players in some shape or form...but...remember this: two types of people run this world: Lawyers and accountants. It is they who make the final strategic decisions because they are able to stand outside the box and determine if the operation will succeed or collapse.
They have determined that on the whole, in the round, at the end of the day - singles beat twins hands down for cost effectiveness. SAFETY really does come second even though the opposite mantra is shouted from the roof tops (this is so that the industry can be seen to be PC).
Example:
15 years ago the FAA and the (now) NTSB came to the conclusion that the design flaw in the 737's rudder screwjack mechanism was cheaper to resolve by paying out to all the deceased familes of those who crashed or would crash in future; compared to grounding the entire global fleet and replacing said defect.
In the cold light of day, these two organisations determined that the final cost to insurance companies of the death of a US citizen was: (1999) $186.
They did the maths. looked at the probabilities and the dollar won - hands down.
Same goes for modern jets flying over the oceans of the world on ONE engine.
RISK = frequency x outcome.
And so it came to pass that on the whole it is better for the organisation to fly singles because the impact of losing one single and its entire crew is marginal/minimal.
UNLESS you are onboard at the time.
I had the inlet guide vanes on my SeaKing (S61) shut in the hover over a sea state 7.
I had a compressor blade go in my AS355 over the middle of a city.
I have had compressor stall in another AS355 incident.
In any or all of those - I suspect my chances of being here today would have been seriously curtailed if those incidents had been on singles. Thus I am biased but in the big picture, my subjective overview is lost in the noise that is corporate diligence and the bottom line: money.
Try responding to this thread thru the eyes of an accountant or lawyer?