Haha, for the last time, there's no issue with the 777. The engines do create drag, but it's nothing extraordinary and compensated for by the wings. It doesn't make a whole lot of relative difference whether they're spinning or not - the L/D ratio remains fairly consistent. The 777 is no worse at gliding than it should be, and better than older-generation planes like the 747. It's probably insignificantly worse than an A330, but that's only because the latter has a more advanced wing design.
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Originally Posted by Jimbuna
Nothing much to do with the topic but the last time I flew across the pond it was in a 777 and I often wondered if I'd be safer in a 747, aplane with four engines as opposed to two.
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It's not any less safe. That used to be the thinking, but once it was realized how extremely unlikely even a single modern jet engine is to fail, it became apparent that 4 engines is actually a disadvantage in every other way. Today, engines have an IFSD (inflight shutdown) probability of something like once every 400,000 hours. That's for one engine! The probability of two engines shutting down at the same time for unrelated reasons is one in hundreds of billions of hours - and if something severe enough happens that would actually knock out both engines on a modern airliner, it would likely knock out 4 just the same (e.g. if you fly into a volcano ash cloud, 4 engines aren't really going to help you).
ETOPS (Extended Twin-engine Ops) regulations that allow twinjets to operate far from land came in 30 years ago. To this day, ETOPS has not failed for any mechanical reasons, as far as I know. There are now planes that have up to 370min ETOPS certification (i.e. they've proven capable of flying on just one engine for over 6 hours without compromising safety). There has never been a dual IFSD in the entire history of ETOPS (except for reasons external to the engines). That's pretty remarkable and I'd say as good of an evidence as you need to know that twin-engine planes are really darn good.