A 22.2m dia helideck designed and built for the unmanned drilling platform MMDP1. The aluminium helideck is supported by an all-aluminium support frame which is 6m high and has a cantilever of 15m. The entire helideck structure is designed to be skidded back on rails to allow jackups to drill thru the conductor locations. The support frame was custom designed to (a) allow structural members to clear equipment on deck below and (b) become a standard support frame design which can be used on all similarly configured platforms. The total weight of the helideck and support frame is under 50MT and replaces a 145MT steel design. Designed for Sikorsky S-91 operations and completed in Jun 2008.