UPDATE 1-Rolls-Royce first-half profit rises as it steps up production

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LONDON, Aug 1 (Reuters) - Rolls-Royce reported a better-than-expected rise in first-half underlying pretax profit on Tuesday as it delivered a 27 percent increase in large civil aerospace engines and said it had manufactured them more efficiently.

The British aero engine maker posted underlying pretax profit of 287 million pounds ($379 million), up 148 percent, on revenue up 6 percent to 6.87 billion pounds.

It said its restructuring savings were ahead of plan.

"Two years ago we set out a programme of change at Rolls-Royce to drive efficiency and sharpen our focus on execution," Chief Executive Warren East said.

"Our strengthened management team is making good progress in simplifying the organisation and driving the pace of necessary change to develop a more resilient and sustainable business."

Underlying profit at the company halved last year as revenue from older engine programmes fell and the company stepped up investment in new technology.

The company is doubling production of its large civil aircraft engines, led by its Trent XWB engine for the Airbus A350, aiming to capture half of the market by 2020.

($1 = 0.7573 pounds) (Reporting by Paul Sandle; editing by Kate Holton)