A simpler machine with a self-generating aerofoil based on the Rogallo was built to replace the Lilienthal glider. The idea again came from books showing the Ryan wing and other developments from the NASSA the space program. We were blissfully unaware of the adoption of the Rogallo for hang gliding in the USA. This machine used the same material and construction methods as the earlier machine but was much easier to build and was lighter.

The films shows different versions of the design as it got bigger to provide sufficient lift for flight. The main problem was the porosity of the wing covering which allowed too much air through. This problem hindered all of the first machines until ripstop nylon was used on machine No 4. In hindsight the high porosity of the sails probable saved our lives as any crashes were from low down. A magazine in the USA was known as ‘Low and Slow’ once wrote in an article that you did not fly higher than you were prepared to fall.

Hand towing was tried to get the machine into the air and this can be seen in the film. Because the bamboo would flex in strong gusts an element of auto stability would occur with excess air spilling out behind the sail. Battens were used in the sail on the latter version.