Britons travelling abroad are likely to be flying in plastic planes in the future, says the chief of Boeing. All 737 planes would be made from non-metal materials, or composites, said president Alan Mulally. Ahead of the Farnborough Air Show, the US plane giant boss said "all future planes will be made out of composites", because it does not corrode. Millions of tourists fly in 737 planes each year. The Farnborough Air Show begins on Monday. Composite are formed when two or more materials with differing properties are combined. Such materials are already used in items such as tennis rackets...