Comment by jballanc | Hacker News Reader

Comment by jballanc | Hacker News Reader

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What the article really missed on mentioning is ETOPS (which is part of the success story of the 787). If you look at the total distance, there are very few routes that can only be serviced by a 747 or A380. Historically, though, many more routes were services by these 4-engine behemoths because of ETOPS rules (http://en.wikipedia.org/wiki/ETOPS).

In a nutshell, ETOPS says how far away a twin-engine plane can be from an airport at any time (for emergency landing purposes). Historically, ETOPS limited twin-engine planes to being within 120 minutes flight time of an airport. More recently, due to experience and engineering improvements, ETOPS regulations now allow many twin-engine planes to be up to 240 minutes from an airport.

For the 787, Boeing is even targeting 330 minute ETOPS. Once they achieve that, there will essentially be no routes outside the range of a 787, leaving passenger capacity as the only reason to consider a super-jumbo. Given fuel costs, and improved route planning, there just isn't enough financial incentive to run a super-jumbo when a modern twin-engine wide-body with ETOPS240 or ETOPS330 will do.

Edit: As a side note, ETOPS improvements are also why all the good ol' 3-engine birds (727, L-1011, DC-10, MD-11) have been put to pasture.

Another important thing to note is that the A380 has, relative to its size, terrible cargo capacity, and using extra hold space to carry cargo in addition to a load of passengers has historically been a lucrative side business for passenger airlines. There are also doubts about whether it would even be possible, structurally, to do a freighter conversion of an A380, meaning that one of the traditional easy ways to squeeze that last bit of money out of a plane (by selling it off to a cargo airline when you no longer want the plane for passenger service) probably isn't an option with the A380. Meanwhile those 3-engine MD-11s and DC-10s are still up in the sky, having undergone freighter conversions to fly for FedEx and DHL and other cargo carriers.

That's also the reason why the 747-8F is the better-selling variant: cargo airlines love the 747 freighters (and from the beginning, the 747 was designed for this, in anticipation of them being retired out of passenger service and replaced by supersonic airliners that never really materialized), even if the passenger versions are no longer a good fit for the market.

A freighter version of the A380 was planned right from the start, and some orders were taken. So it's certainly possible.

But that doesn't mean it would be economic.

For various reasons - not least fulfilment delays because of manufacturing issues - the A380F hasn't been prototyped yet, and probably never will be.

A freighter-from-the-beginning variant could be possible. But knowledgeable people I've heard from say that taking a passenger A380 and doing a freighter conversion is probably either not possible due to the internal structure of the plane, or if possible would end up costing more than the resulting plane would be worth.

> all the good ol' 3-engine birds [..] have been put to pasture

.. except in cargo operations, where the MD-11F is all the rage. Cargo is exempt from ETOPS, which is why you see trijets still operating for FedEx, DHL, etc.

edit: I see ubernostrum said almost the exact same thing below! I'll leave the comment, as he/she didn't mention the ETOPS cargo exemption.

It should also be mentioned that ETOPS covers not only the plane, but also the airline. For example if replacing the engines, then the work will be done by two different teams as it less likely they will make the same mistake. Consequently we now have aviation headlines like the 747-8i (with 4 engines) getting ETOPS (t stands for twin) http://atwonline.com/manufacturers/boeing-747-8i-gains-330-m...

FYI according to Wikipedia the "t" longer stands for twin in FFA usage.

"The FAA has decided to use the single term, 'ExTended OPerationS,' or ETOPS, for all affected operations regardless of the number of engines on the airplane."

(my capitalisation)

http://en.wikipedia.org/wiki/ETOPS

And colloquially, "engines turn or passengers swim."

> http://en.wikipedia.org/wiki/ETOPS

That wikipedia page desperately needs a more readable introduction. Thanks for the info.

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