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One way to capture the civilian aerospace boom is to sit in the cockpit with Airbus and Boeing. Another is to book a window seat overlooking the engines, alongside Rolls-Royce. There is a difference. The former earn their profits by making and selling airplanes. But manufacturing is only half the story in the engine business. Some 50 per cent of Rolls-Royce’s £12-billion ($18.6-billion) revenue for 2012 comes from maintenance, repair and overhaul (MRO). The company can monitor its newest engines in the air and alert airlines if action is required. One day, all manufacturing might look like this.