A key component of the highly mechanised weapons handling system (HMWHS) for the new Queen Elizabeth Class aircraft carriers has completed factory acceptance testing.
The HMWHS provides mechanical handling facilities for moving palletised munitions around the deep magazine and weapon preparation areas, and a series of weapons lifts to connect the magazines, hangar, weapons preparation area, and flight deck.
The components in question, designed and delivered by Babcock’s marine and technology division, are 56 so-called ‘moles’, which do the lifting and carrying of the palletised munitions in the magazine. The HMWHS system consists of a network of two versions of these prime movers, which traverse forward and aft (longitudinal, version one) or port and starboard (athwartships, version two), each able to lift and move a payload to locations within its predefined area of travel. The moles can transfer payloads between each other, so the payloads can be located anywhere within the magazine.
The two mole versions are different shapes to enable lifting and lowering of the palletised munitions in the correct orientation, onto the set stowage and transfer positions, and are equipped with electric traverse and lift drives, allowing accurate positional control within the magazine. A number of lifts provide interconnection between the magazines and the hangar, weapons preparation area, and flight deck, and a mechanism enables the mole to access the lift platform without needing to disengage and re-engage the pinion from the rack. The magazines are unmanned, with all the moles controlled from a central location, so personnel are required only where munitions are being prepared for storage or use.
A significant challenge in manufacturing the moles has been the achievement of the tight tolerances introduced following completion of the demonstration phase, to speed up assembly.
Factory acceptance testing took place at Babcock’s site at Whetstone, Leicester, and included dimensional and functional tests and inspections of the parts and mole drive and lifting systems. The moles have now been delivered to the Aircraft Carrier Alliance’s central warehouse, ready for installation once the fixed rail equipment and lifts have been installed. As the moles are fully re-assembled, installation will involve placing them in the magazine and electrically connecting them to the rest of the system via an energy chain system.
“The moles are a critical component of the HMWHS and successfully completing FATs for all moles marks an important milestone in delivery of the system,” said Matt Hatson, Babcock’s director of integrated technology. “The HMWHS is the first maritime application of shore-based commercial warehousing processes using automated systems with all-electric control, adapted for safe transport and stowage of munitions in a warship environment. Munitions can be delivered, in bulk, to the point of use at rates that could not be achieved manually, while minimising the manpower requirement in what is traditionally a labour-intensive process, thus delivering reduced through-life cost, as well as a saving in onboard living accommodation requirements.”
Production of the final software solution for the HMWHS integrated control system, and manufacture of the various mechanical, electrical, hydraulic and pneumatic sub-systems making up the HMWHS are now underway, of which successful completion of FATs for all moles is part. The final equipment for the full HMWHS for the first carrier will be delivered by May 2013, and for both vessels by February 2015.