But today The News can reveal the truth about how HMS Invincible – supposedly in a state of 'extended readiness' – is in fact a warship far from ready for action.

The Ministry of Defence claims she is available for action until September 2010, when she will leave the fleet.

But a Freedom of Information request by The News reveals she is crewed by just four people as she languishes in Portsmouth's dockyard.

She has been raided for spares – her engines have been stripped out and her propellers have been seen lying on her deck.

And far from being ready for service, navy sources say it would take around 18 months to prepare Invincible for use – a period which would take her well past the date she is scheduled to end her days in the Royal Navy.

Her sorry state is a far cry from the description of her on the Royal Navy's website which claims she can be counted among the navy's finest.

The description refers to her decommissioning in 2005 by saying: 'This process is often mistaken for being withdrawn from service but we are still very much 'part of the fleet'.

'In fact Invincible will remain available to the navy until 2010.

'This forms part of a long-term plan to assist with the introduction of the new CVF Aircraft Carriers, HMS Queen Elizabeth and HMS Prince Of Wales.'

Portsmouth South MP Mike Hancock, who sits on the Commons defence committee, said: 'Saying HMS Invincible is part of the fleet and available to the navy is the same as saying the Marie Celeste had a full ship's company in healthy mood.

'All of our ships bar submarines are visible to anyone and it doesn't take a genius to work out that Invincible isn't going anywhere.

'The navy should be more open, and not claiming capabilities we don't have.'

Former naval officer and editor of Warship World, Mike Critchley, said: 'As far as I'm aware she doesn't even have her anchors, which tells you how likely the chances of her going to sea are.

'She has been stripped of most valuable items for the other carriers, which makes sense, but that means the only time she is going to sea is when she leaves for the breaker's yard.'

Despite The News's findings, the Royal Navy insisted the carrier was still available to the fleet.

A navy spokesman said: 'It is not Royal Navy policy to discuss the readiness state of any warship for operational reasons.

'The position is that HMS Invincible remains within the Royal Navy fleet and remains available until the time that she leaves service.

'Four navy personnel remain on the scheme of complement of HMS Invincible and act as a full-time caretaking unit.'