Basically, ETOPS is decided on how long an aircrfat could fly over ocean if it lost an engine. This is different for each aircrfat so different arcraft hve different categorys. Initially, it was 90 minutes from land but it is now 180 with advancements in engine reiability. Other considerations are made such as what is th cabin fire fighting facilities like, and even goes into if they have defribilaters on aboard. However, private jets are exempt from this rule.
By the way, dopn't be nervous to repost things. I have been on A.Netters for around a year, and i have done it a couiple of times. You will get some people who will slaughter you for it, but just ignore them and welcome to Airliners.net.
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