As I understand it, pressurization cycles introduce the most stress on an airframe so maintenance intervals are tied to it. However, not all planes are equal in that regard, a long haul flight in a 747 might easily take 10 hours counting for one pressurization cycle while a 737 can do 6 trips in that time. Are short-haul planes build "sturdier" in this regard than their long-haul counterparts so that they are able to better cope with the amount of stress? And/or do they have to go into maintenance more often?
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2$\begingroup$ It also differs by operator. Operator A can own a 734 which flies 6 legs per day on only short haul flights. Operator B might own another 734 which flies mid-haul and only 2 legs per day. $\endgroup$– SimonCommented Mar 30, 2016 at 15:18
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2$\begingroup$ Short haul planes are generally narrow-bodies which are naturally sturdier than wide-bodies, just because they're more compact and have less potential for flex $\endgroup$– Jon StoryCommented Mar 30, 2016 at 15:52
1 Answer
Yes, short range airliners are designed for up to 90.000 cycles whereas long range airliners can be designed for 40.000 cycles or less. And it is not only the pressurized cabin that needs to be designed for more load cycles, also the landing gear has a lot more work to do. This should become clear when you calculate how many miles/kilometers an airplane will taxi in its life and compare that to the design life of a regular car.
Your average short range airliner will easily taxi 5 times more miles in its life than your average car will drive.
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$\begingroup$ I never thought about the taxiing, that's really impressive! $\endgroup$– JustSidCommented Mar 31, 2016 at 11:48
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1$\begingroup$ I must have missed this question the first time 'round. Peter, can you give some examples/calculations for the taxi distances. Many cars, in the US at least, will drive well over 100k miles (~160k kilometers), and I'm having a hard time grasping that a plane will taxi that distance. Fly? Certainly, but taxi? Maybe I should make this a whole new question. $\endgroup$– FreeManCommented Oct 14, 2016 at 14:00
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1$\begingroup$ @FreeMan: Assume 1500m for both the take-off and the landing run, add taxi distance to and from the terminal, and on a big airport this will add up to 8 or 10 km of taxi distance per cycle. Times 90,000 makes three quarters to a million km in taxi distance. If one airport on a leg is smaller (5 km taxi), the total is still almost 600,000 km. $\endgroup$ Commented Oct 14, 2016 at 16:01
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$\begingroup$ Thanks, @PeterKämpf. I guess I never really thought about how far a plane really taxis. It does add up quickly. I guess part of it is that an airframe will usually be used for 30 years or so, but most cars are disposed of after 10-15. $\endgroup$– FreeManCommented Oct 14, 2016 at 17:36
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$\begingroup$ 90.000? That would be 5 cycle a day for 50 years without interruption ! $\endgroup$– AntziCommented Oct 15, 2016 at 1:16