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by Recoil42 4696 days ago
I don't objectively agree with the latter point, but rdl is correct about the former. It takes high altitudes for tubofans to come into their element in the efficiency gradient, and short routes don't really stay in that area of altitude long enough to give them an advantage. Turboprops are more efficient at lower altitudes, which is perfect for short hop flights -- where you're spending half of the time climbing/descending anyways. This is partly why Porter Airlines in Toronto flies Q400s.
1 comments
rdl 4696 days ago
They're clearly objectively better in a lot of ways; you could just argue that they're not net-better overall, since there are also advantages to twins. Single is undeniably cheaper to buy/operate. Since you never push off without both engines good, there's no way a twin would have higher dispatch rate than a single (since there are ~twice as many parts to deadline your aircraft).

You may still value "has extra engine in case one dies in flight" more than this, though. (and I did, until I saw how singles actually had approximately the same safety stats as twins, at least for private pilots most like what I'd be.)

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Recoil42 4695 days ago
I wonder if twin-engined aircraft are less better maintained for the reasons you mentioned. Since you only have one engine to 'push off' with on a single, you better make damn sure it's in good working order.
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rdl 4694 days ago
That's ETOPS vs. 3/4 engine aircraft, I believe, but I don't think the maintenance and reliability standards are appreciably different for civilian 1 vs. 2. Mainly because no scheduled service is done using a single engine, so it doesn't even come up.

I'm pretty sure military maintenance standards are so entirely different that their extensive experience with single engine aircraft isn't meaningful -- plus, their singles are mainly either very military specific (F-16 and other light fighters) or historical. Most of their transport aircraft have something in common with commercial, now, except maybe C-130s. And the USN has generally favored twin vs. single for "reliability over water" anyway.

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