Up to 13,500 military personnel will help provide security during next summer's Olympics – almost double the 7,000 that had been expected.
The Ministry of Defence said the servicemen and women would be on hand across the UK to protect 150 venues and training sites.
HMS Ocean and HMS Bulwark will also be based at Greenwich and Weymouth Bay respectively. Typhoon jets will be stationed at RAF Northolt. Puma and Lynx helicopters will operate from HMS Ocean.