In autumn 2009 we stumbled across an old two stroke outboard which it’s owner was trying to sell. Although the motor had severe overheating issues, the price was very interesting. After some surfing on the net it was identified as a Yamaha 15A built sometime between 1972 and 1978. We were even lucky enough to find a complete parts list with diagrams. As could be guessed from the model number it is a 15 hp motor. It came with a 9 1/4 x 11 1/4 propeller and weights about 37kg.
Last week (20.08.2009) we decided to have a go with a new set of foils. Fully submerged T foils this time, with two flaps per foil. Altitude, roll and pitch are controlled by the “pilot” with an old RC transmitter. The potentiometers of the transmitter are directly wired to a micro controller which processes the three inputs and with the aid of mixing functions generates four outputs.
This is a short write up of our 2009 Easter project. We had been thinking about the realisation of a hydrofoil boat for a few years but never really began to design or build one. The fact that we study at different universities separated by a 7 hour drive did also not help.