oldbilbo
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.....Further delays due to a range of technical and programme issues brought the programme to a position of 57 months late and 53 per cent (or £1.35 billion) over-budget by November 2009, with a forecast cost of £3.9 billion for the first three Astute boats....
....The system receives data from the boat's sensors and displays real time imagery on all command consoles. The submarines also have Atlas Hydrographic DESO 25 high-precision echosounders, two CM010 non-hull-penetrating optronic masts - in place of conventional periscopes - which carry thermal imaging and low-light TV and colour CCD TV sensors- Wikipedia
.....And the intercom doesn't work.