Watch Scrapheap Challenge online: Episode 12 Flying Machines

The challenge This week it's the build to end all builds. Returning champs from last year, The Anoraks, take on the new wearers of the Scrapheap crown, The Powerlifters. The teams have but 20 hours to build what da Vinci himself couldn’t master – human-powered flight. The Anoraks Off-roading enthusiasts from Surrey, The Anoraks, Geoff, Lyndon and Marc, were the champions of series seven in 2004 and are back to defend their title. Geoff and Lyndon work in the technology industry and Marc is a 4x4 mechanic. They spend their spare time in Marc’s garage, building and restoring Land Rovers and other 4x4s. Lyndon claims he has broken, crashed and sunk more Land Rovers than he has had hot dinners; Geoff claims to be very good at hitting things with a hammer; and Marc likes to think he is the stabilising influence of the team. Team expert Billy Brooks is chief designer and director at Pegasus Aviation, as well as a pure genius and Scrapheap legend! Billy has previously been beaten by his rival expert Darren on Scrapheap Challenge and is very much looking forward to battling it out with him for a second time. The Powerlifters Neil, Mark and Dave are true Scrapheap! These boys love their drag racing and hot rodding and are all forklift maintenance engineers in Essex. Bald, tattooed and pierced, Neil and Dave provide the main double act but gentle giant Mark doesn’t seem to mind playing the fall guy to the duo. Energetic and with a range of outside interests, The Powerlifters are hardworking, straight talking, great fun, and claim to be able to take on anything Scrapheap can throw at them! Team expert is British Airways captain Darren Arkwright. He met his rival expert Billy in Scrapheap’s first venture skywards, a challenge called Gliders. Darren beat Billy on that occasion and knows that Billy is very much up for revenge! The judge Hong Kong-born Freddie To studied architecture in London at the Architectural Association school of Architecture. He designed and built the first solar-powered aircraft to fly in Great Britain, Solar One, which flew in 1978 and he built a human-powered aircraft, Phoenix, which flew in 1982. He has also developed and produced an inflatable wing for skydiver Yves Rossy, as well as shoes which allow you to walk on water.

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