The weapons system for the navy's new destroyers is one step closer to working after an investigation into test failures.
The MoD and its commercial partners were left bemused when the multi-million-pound Sea Viper system failed in November during routine testing, as revealed by The News.
It is the main defence weapon for the 1bn Daring class destroyers, the first of which is due to enter full service at the end of the year.
But an investigation into the firing off the south coast of France found that it was a design flaw with the Aster missiles - rather than a problem with the launcher or control system. The missiles are now being redesigned and a new firing is planned to check if the system works properly.
An MoD spokeswoman said: 'Some production weaknesses in the most recent batches of the Aster missile have been identified and these are being corrected through minor re-design work.
'Sea Viper is undergoing a rigorous test programme to ensure that all aspects of this complex system have been thoroughly trialled and any problems resolved before it enters service.'
Four test firings of the Sea Viper System have so far taken place - but two have not met their trials objectives.
Portsmouth South MP Mike Hancock, who sits on the Commons defence committee, said: 'I am very sceptical about this - are we really to believe that a whole batch of missiles was just made wrong for such an expensive system? If you read this in a novel it would be believable, but when it's a programme that is already late it's incredible.
'I think the only way we can be certain that the problem is resolved is when these missiles are fired from a moving ship, and not from a static platform off France.'
The MoD has said the problem with Sea Viper is not due to cause a delay to the delivery of the system to HMS Daring and Dauntless.
The first test firings of the system are planned to happen on Dauntless, the second ship to arrive in her base port of Portsmouth.
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