13:34 GMT, November 9, 2009 Close teamwork between Babcock, the UK Ministry of Defence (MoD) Design Authority based in Abbey Wood, and ship’s staff has successfully achieved a gruelling programme of work in HMS Talent. The 20 week maintenance period at Devonport Royal Dockyard has delivered the submarine on-time to Fleet, ready for operations, supporting the high readiness SSN force.

The work required in HMS Talent included the first double motor generator (MG) rotor and main battery change to be undertaken on the waterfront. This was a substantial and complex work package to achieve alongside, with the systems live, and something that had not been done before outside a major refit in dry dock, so to undertake this successfully in a tidal berth was a significant achievement.

The main battery change involved 112 acid battery cells, each weighing 0.5 tonnes, having to be manoeuvred from the battery compartment to the dockside and 112 new cells shipped into place. Equally, each of the two 8 ft long, 2.4 ft diameter MG rotors, each weighing 2.4 tonnes, had to be shipped from the congested diesel generator room through the aft end of the submarine and out of the engine room hatch – a route with very tight clearances throughout. This was a highly complex operation to lift and manoeuvre these extremely delicate pieces of equipment and required considerable skill and control, particularly as the operation had to be completed twice, and given the logistics constraints of the tidal berth (including ship movements and sharing craneage with other platforms). A further challenge included the submarine having numerous live systems that had to be released to allow removal of the rotors.

A single MG rotor change would usually take around 70 days, and a battery change 25 days, in dry dock or basin conditions. In this instance the two MG rotors were changed in highly challenging circumstances in just 105 days.

Close co-operation between Babcock’s boat manager, production manager, trials manager, and ship’s marine engineering staff was essential to ensure all necessary considerations were incorporated into the programme. This critical path schedule was then rigorously controlled to ensure success of the project.

The very intense programme of work also included major intrusive work on the gearbox to identify and rectify an emergent defect on the main wheel and bearing; a full hull and systems surveillance inspection and revalidation programme including non-destructive examination of the torpedo tubes; the introduction of emergency oxygen generator lockers; and additional emergency breathing system couplings in the junior rates bunk space.

Babcock submarine operations director Devonport Gavin Leckie commented: “To have achieved such an onerous workscope within a LAMP [Long Assisted Maintenance Period], on the sea wall, was a considerable challenge and is testament to the effective close working and skill levels of the joint team involved. This is an excellent result. By working hard to meet the requirements and complete this programme within the timescales involved the team has ensured that HMS Talent is fit and ready to meet her long-term commitments within the SSN availability programme.”

Captain Mike Robinson, Superintendent Upkeep Submarines at Devonport, said: “The requirement to conduct this significant package of work in HMS Talent was identified following a short notice change to the submarine operating programme. The short notice of this change and the urgency to return HMS Talent to operations has necessitated a huge effort within the Devonport submarine support community. To have achieved all this to programme and cost is a significant and admirable achievement by the Devonport team.”

Following successful completion of the LAMP this month, HMS Talent will be available for deployment before Christmas.