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Ambush submarine hits important milestone

Ambush, the second hunter-killer submarine in the Astute Class, has successfully completed her first dive; an important milestone in readiness for the boat’s departure on sea trials early next year.

The dive, known to engineers as ‘the Trim and Inclining Experiment’, proves the boat’s safety and stability in the water and measures the submarine’s performance at a depth of 16 metres. The maiden dive took place over two days and involved more than 70 people including BAE Systems’ engineers, Ministry of Defence personnel and Royal Navy Ship’s Staff.

Commander Peter Green, Commanding Officer of Ambush, stated:

“This is a major milestone for Ambush and shows she is firmly on track to exit Barrow early next year in order to commence her sea trials. Nuclear submarines are some of the most complex machines on earth and therefore to see everything come together in order to dive the boat for the first time is very satisfying. It has been a superb team effort between BAE Systems Submarine Solutions, the Ministry of Defence Submarine Project Team and Ambush Ship’s Company.”

The ‘Trim and Inclining Experiment’ proves the safety and stability of the submarine and sets the standards of operation for Ambush’s performance.
The experiment takes place in a dedicated deep area of the dock at Barrow-in-Furness known as the ‘basin’ or ‘dive hole’, where a set sequence of preparations is made, including diving the submarine on its main ballast tanks.

Ambush sea trials are set to commence in 2012.




  • It is fabulous to see that BEA of Barrow-in- Furness proudly continues its tradition of building the best submarines in the World to serve this Nation, long may this continue.

  • BAE