Now THAT is a show of strength: HMS Ocean arrives in the Thames to protect London during the Olympics (and if she doesn't put off the terrorists, what will?)

HMS Ocean sails up the Thames as preparations for Olympic security continues



Phil Hammond reveals he has been trained on terror decisions such as shooting down a hijacked jet


The Army has done it, as has the airforce. And now the Royal Navy has arrived in London to show off the weapons it hopes it never has to use at the London Olympics.

HMS Ocean - the largest in the Navy - slipped up the Thames on Friday, past the tidal barriers, and up towards Greenwich to check out the berth, where it will monitor and protect London during the Olympics this summer.

The hardest part of the journey was slipping past the Thames barrier, which at only 60m gave some clearance on each side - but not much in terms of margin for error.

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Welcome to London: The UK's largest warship HMS Ocean nudges its way through the Thames Barrier bzck in May on the way to docking at Greenwich

The Carrier HMS Ocean takes up her position in the Thames during security rehearsals for the Olympics back in May

Test run: The exercise is aimed at testing military capabilities to ensure operational readiness before the start of the Olympic Games The show of strength came as Defence Secretary Philip Hammond said today he was prepared to to give the order to shoot down a hijacked airliner if the Olympics were threatened by a 9/11-style attack. Hammond told the Evening Standard: 'The decision to engage would be made at the highest levels of government.' RELATED ARTICLES Previous

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Next Now Argentina uses Olympics to highlight Falklands claim: TV... Olympics construction boss in planning dispute over proposal... Share this article Share Asked if he was personally willing to give the order to destroy a rogue aircraft, he said: 'Of course ... I’m certainly prepared to make decisions.' Mr Hammond added that Londoners and visitors 'should be reassured by the military presence - there is no risk from the equipment. It’s defensive in nature and pointing skywards.'



The amphibious assault ship is being positioned in Greenwich to provide extra security for the London Olympics A SHIP THAT'S ONE OF A KIND

HMS Ocean was commissioned in September 1998 at her home port Devonport, Plymouth, after being built by Kvaerner Govan Ltd on the Clyde and fitted out by VSEL at Barrow-in-Furness. She is the sole member of her class in the Royal Navy, designed to support amphibious landing operations and to support the staff of Commander UK Amphibious Force and Commander UK Landing Force. The ship carries a crew of 255, an aircrew of 206 and 480 Royal Marine Commandos. An additional 320 marines could be accommodated in a short-term emergency. HMS Ocean is capable of transporting and sustaining an embarked military force of up to 800 people equipped with artillery, vehicles and stores. She has capacity for 40 vehicles but is not designed to land heavy tanks. There are four LCVP Mk5 vehicle/personnel landing craft on davits. The ship has full facilities for 12 EH101 Merlin and six Lynx helicopters, plus landing and refuelling facilities for Chinook helicopters. Twenty Sea Harriers could be carried but not supported. The flight deck is 170m long and 32.6m wide, with two aircraft lifts. Its weapon systems include four Oerlikon/BAE twin 30mm guns together with three Raytheon/General Dynamics Phalanx Mk15 close-in weapon systems. Questioned how he would deal with a hijacked airliner full of passengers, he said: 'We rehearse these things, we train for them. 'All the ministers involved are fully versed in the processes they have to go through, the judgments they have to make. 'I’m not going to spell out precisely who is in the loop and who is not, but there are a number of ministers who are involved in the air defence arrangements. The decision to engage would be made at the highest levels of government.' Mr Hammond, who was taken on board HMS Oceans by a landing craft, said of the security arrangements: 'I don’t think it’s over the top. Every Olympic Games in recent times has had a significant military component to its security plan.' Arrangements for security has been ongoing for the last few days, with HMS Ocean now making its debut appearance. The ship will remain in Greenwich throughout the summer games. The warship, which has the motto 'Boldly Faithfully Happily', will have quite an army on board - 300 military personnel will base themselves on the ship, while eight Lynx helicopters with sniper teams onboard will be ready to lift off at a moment's notice. It is part of huge military protection for the city, with Typhoon jets stationed at RAF Northolt, and ground-to-air Rapier missiles dotted on rooftops at six sites across the city. Defence Secretary Phillip Hammond said: 'Whilst there is no specific threat to the Games, we have to be ready to assist in delivering a safe and secure Olympics for all to enjoy.' Rapier surface-to-air missiles have also been showcased at Blackheath Army Cadet Centre, in south east London, as part of the massive 2012 security test on land, sea and in the air. Weymouth and Portland in Dorset will play host to the sailing where the Albion-class amphibious assault warship HMS Bulwark will play a key role in protecting the events. Colonel Jon Campbell, commander of the Joint Ground Based Air Defence, said: 'We have done as much as we can to allay people's fears. 'The Rapier system has a world-class radar on it and is particularly good at picking up low and slow-moving objects in the sky. It means we're able to get the very best picture of what is happening in the skies of London.' Air Vice Marshall Stuart Atha added: 'We want the focus to be on Usain Bolt this summer and not us. We're very proud to be part of this plan to deliver a safe and secure Olympics.' The Lexington Building in Tower Hamlets and the Fred Wigg Tower in Waltham Forest, both in east London, have been identified as potential sites for the High Velocity Missiles.

Members of the public watch as the HMS Ocean passes Greenwich Naval College

Rapier missiles would be positioned on Blackheath Common and in Oxleas Wood, both in south east London, and at William Girling Reservoir Chain in Enfield and Barn Hill at Netherhouse Farm in Epping Forest, both in north London, should the Air Security Plan be approved by the Government.

Col Campbell said the sites had been chosen to avoid having weapons inside the Olympic Park.

He said: 'We're trying to de-militarise this and let the sport do the talking. The Lexington Building is the best available location away from the Olympic Park.'

Heading to England: The HMS Ocean earlier today, out at sea, making its way to the Thames Ready and waiting: The Typhoon jets line up on the tarmac at RAF Northolt, west London, ahead of a nine-day military exercise to test security for the Olympic Games

What the...? A man walks past a Rapier short range air defence system at Blackheath, London, ahead of the exercises

We got your back: Surface-to-air missiles at the army cadet base in Blackheath, southeast London

The Rapier surface-to-air missile has the power to take down a Boeing 747 full of passengers if needed to protect a stadium full of 80,000 Olympic spectators in a terrorism nightmare scenario.

The British military has insisted that the missiles - with a range of up to five miles - could be deployed as the last line of defence. Experts say the likelihood that they will be fired is slim to none.

Downing an aircraft would still cause debris to rain from the sky, high casualties and fires.

Ready to roll: Royal Marine commandos in rigid inflatables, from the Royal Navy flagship HMS Bulwark, take part in a security exercise off Weymouth and Portland

When you launch a Rapier missile and shoot down an aircraft, it's not like the whole thing vanishes. It's 100 tons of metal, scraps, and other stuff that is coming down,' said Jan Wind, a retired Dutch Navy captain who is director of the Hague-based Wiser Consultancy.

'If a Rapier is used, the damage could be just about the same as the intentions of the terrorist - only on another spot. The goal of the terrorists will be met in a certain sense,' Wind said.

It's rare for the British military to publicise the location of its weapons, but the military says it hopes that any potential attacks will be deterred by showing the missile strength and other defense assets such as Typhoon fighter jets.

Ground-to-air missiles have been a fixture of Olympic games and large VIP events in the post-9/11 world, but London's missiles have sparked outrage among residents of an apartment block who learned that the Rapiers might be stationed on their roof.

They say the missiles are creating a climate of fear - which security experts say is exactly the point. That's because the systems are more valuable as deterrents than as deployed weapons, Mr Wind said.

'The British army and air force don't do all this to really shoot down a terrorist aircraft, they do it to display their determination to do so, which will hopefully prevent the terrorists from attacking,' Mr Wind said.

'If you know that there are 500 policeman outside the jewellery store, you will not go there and try to rob the store.'