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W0X0F... I fly from Dublin to USA a couple of times a year as I love coming to the states when I can!
I am wondering what makes flying for that long over the ocean so safe? Obviously you can't make emergency stops here so the flights have to be incredibly safe?
Not really sure how to word the question that is in my head. I guess I am looking for some proof that it is safer flying in these transatlantic planes over a standard Dublin-London plane
I really hate flying but do it because I know I have to so anything you can say to make me feel a bit better about the experience would be appreciated!
Safety in aviation is all about mitigating threats. On the mechanical side we do this with reliability of systems and redundancy of the really critical ones. On the human side, we have training that emphasizes standard procedures and checklist usage.
Healthy engines are obviously critical to safe flight and the first passenger flights across the ocean were in four-engine recips (prop planes with reciprocating engines, such as the DC-6 and DC-7). And they needed this redundancy. It was not at all unusual to have an engine problem back in those days, so you really needed the extra safety margin. Reciprocating engines, by their nature, are just more prone to mechanical problems. Whereas a jet, or turbine engine, is simply spinning, a reciprocating engine is, in a sense, just beating itself to death.
When the jet age began, you had four-engine jets (707, DC-8) making the ocean crossings. The reliability became immediately obvious and soon three-engine jets (DC-10, L-1011) joined the planes crossing the pond. But it was a long time before we had twin-engine jets on those routes; the redundancy was considered too critical.
As the reliability of jet engines improved over the years, the idea of extended twin-engine operations (ETOPS) over water became feasible. The engines on trans-oceanic planes are not inherently more reliable than those on domestic flights (can you imagine trying to justify a less safe engine for domestic routes?) but ETOPS planes are checked by mechanics prior to each crossing and statistics are kept on the reliability of each company's ETOPS fleet.
If reliability levels fall, the company's ETOPS certification could be revoked, or more restrictive ETOPS requirements might be enforced. For example, they could be temporarily limited to ETOPS 60 rather than ETOPS 120 or 180. The number is a measure of how close the plane must be, measured in minutes of flying time, to a suitable divert field. A lower number means a longer route and this, of course, translates to time and money.
Last edited by W0X0F; 03-23-2015 at 09:51 PM.