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A350XWB, the Plane Airbus Did Not Want To Build, Makes Maiden Flight
McGruber writes "The BBC reports that the Airbus A350XWB (extra wide body) has made its first flight. Like the Boeing 787, the A350 offers airlines the chance to combine long-range services with improved fuel efficiency. The A350's fuselage is made of carbon fibre reinforced plastic, while many other parts of the aircraft use titanium and advanced alloys to save weight. It also has state-of-the-art aerodynamics, and engine manufacturer Rolls Royce has produced a new custom-designed power unit. Airbus claims that all of this means the A350 will use 25% less fuel than the current generation of equivalent aircraft. It also points out that noise and emissions will be well below current limits."
Does any manufacturer really want to design new planes? The engineers do, it's their job & mostly their passion but the shareholders won't want to if they don't have to. Every time you design a new aircraft you commit to billions of investment and lots of risk, both financial and technical.
The saying I was most often quoted in my aerospace degree "How do you make a small fortune? Start with a large fortune and invest in aerospace".
The best that you'll probably get is that once it becomes clear that a planned development needs to start that the shareholders decide to go all-out for it, and the rest of the company commit to it 100%.
Boeing announced the Boeing 787 right after Airbus committed to the A380 - Airbus was going for the VLA market, which Boeing had dominated since they launched the Boeing 747 in the 70s as they had no effective competition in that particular market segment.
Once Airbus committed themselves to the VLA segment, Boeing committed itself to the smaller 250 seat segment, in which it already had an aging product in the Boeing 767 - sales of which were rapidly tailing off, and customers were demanding something more efficient.
Airbus responded by announcing a package of updates to their A330 airliner, but customer demand was poor - a lot of large customers wanted an all new fuselage design (the Airbus A330 and A340, both circa 1990 in vintage, used the same fuselage as the A300, which preceded them by 20 years), and carbon fiber as a primary structural component, so Airbus went back to the drawing board and came up with the A350XWB.
Its an aircraft that "Airbus didnt want to build" in the same vein as Boeing "didnt want to build" the Boeing 787, as that program only came about after customers outright rejected Boeings Sonic Cruiser concept in the years leading up to the 787s program launch - the 787 uses many of the same technologies (the carbon fiber barrels for the fuselage), and is a direct follow on from a prior program that was rejected by customers.
Interestingly enough, the Airbus A330, which customers didn't want an updated model of, has sold well over 500 aircraft since that "rejection". You never can tell....
These planes will still be flying in the 2030s.
Since these planes won't suffer from metal fatigue like planes made out of aluminum, that means that they'll last longer?
Metal aircraft don't necessarily have to suffer so badly from metal fatigue that they have to be replaced inside of 15-20 years. Fatigue depends on usage patterns and there are 747 still flying after 30 years of regular use and with good maintenance should be able to last at least the better part of another decade. USAF engineering studies project that their B-52 fleet would not reach the fatigue limits of it's wing structure until the 2040s but keep in mind these B-52s do not get flow as hard as the 747. The B-52s that are now in service left the factory in the mid 1960s. An American airforce veteran I met a few years ago told me that there are actually cases of the third generation of soldiers from a military family flying B-52s. Dunno if that's true but theoretically it sure could be. Just about the only criticism you can throw at the B-52 is that it could do with an upgrade to more modern fuel efficient engines which Boeing estimated would increase it's already impressive loiter capability by 46%.
Only to idiots, are orders laws.
-- Henning von Tresckow
Metal fatigue in airliners is driven by several factors: humidity of the air in which they are operated (for example planes the spend their lives in Hawaii suffer more than planes that operate mostly in the southwest of the US) the number of pressurization cycles (the fuselage acts like a balloon.... the structure inflates a bit when pressurized and relaxes when below approx 8000 ft... therefore planes that spend most of their hours on long flights last longer than those that have fewer flight hours but made many short flights) plus the usual mechanical (bending)stresses any plane would experience.
Composites are not immune to stress and failure... they are just different. Composites are less sensitive to moisture (which means dreamliners can have more comfortable moister cabin air without contributing to structural wear) they handle the pressurization cycles better (so planes like the dreamliner can pressurize their cabins more to make passengers more comfortable at altitude) and so on. Composites also have an interesting thermal reaction: they soften a bit in heat (making them slightly less-suited to hot weather ... a possible issue on the ground in hot places, but not at altitude where it's cold even over the equator) but they actually get stronger as they get colder (so composite planes are actually stronger and safer at high altitudes). Composites are made of various fibers embedded in various types of plastics (resins) and their strength comes from the fibers as long as the plastic holds those fibers together properly... but the resins are much more sensitive to heat and particularly sunlight than metal. How the resins will hold-up after 20+ years of high-altitude exposure to the sun (higher UV etc) is a bit of a question... materials science people can simulate this stuff, but nothing beats real-world exposure and real-world operating conditions. If those resins age poorly and become crumbly (and less sticky, therefore less able to hold the fibers in place) then these airframes will have shorter service lives.... but they will still probably win-out because of all the monetary savings that their increased efficiencies provide during those service lives