"Our long-term contracts continue to provide us with excellent visibility of future revenues, and we have three-quarters of expected sales already in place for the current year," Chief Executive Archie Bethel said in a statement.

The group predicted it would continue to achieve mid single digit organic revenue growth at constant exchange rates, with broadly stable margins this year and over the medium term.

In the 12 months ended March 31, underlying pretax profit reached 494.8 million pounds, on a 7.7 percent rise in revenue to 5.22 billion pounds.

Net debt fell 4.5 percent to 1.17 billion pounds, or 1.8 times earnings before interest, taxes, depreciation and amortisation.

The specialist engineering and technology-related services company said orders stood at 19 billion pounds, with a 10.5 billion pound pipeline.

At constant exchange rates, organic revenues rose 4.9 percent, with underlying operating profit up 5.3 percent in the same terms.

(Reporting by Elisabeth O'Leary; Editing by Mark Potter)