Aero-Sport International Kahu
Chris Wade commenced the initial theoretical design and research in 1997 as the sole designer of the aircraft and the highly modified Mazda Ml3B rotary engine. The actual construction for the first prototype started in August 1999. A lot of time was spent in the initial design phase and this has allowed ASI to perform trials without any major deviations from the original design. Minor problems with quality and suitability of imported componentry have now been resolved and results of recommendations from the test pilot, CAA and other consultants have seen several modifications during the testing phase. The size of the wheels being a significant change. On 27 July 2001, at Tauranga airport, New Zealand, the prototype underwent its first official flight with Rob Sanders as test pilot. The original configuration allowed prototype testing in the Microlight category.
Nearing the end of the flight testing programs a number of improvements to the original prototype were incorporated. A new mechanical pre-rotator replaces the original hydraulic design which was not considered efficient enough. The new version is capable of spinning the rotors to 275rpm. The horizontal stabiliser effectiveness has been improved by raising it into the centre of the prop wash. Yaw stability has been improved by moving the vertical stabilisers into the last one third of the prop wash which also increases airflow over the rudders. This has particularly improved control at low airspeeds of 15 knots and less. The rotor head and mast assembly is now fully adjustable for different weight and balance characteristics. The original reduction drive was a Mazda gearbox which whilst successful, came with a significant weight penalty. A Hirth gearbox has been used to simplify testing of gear ratios, however it is planned to use a geared tooth belt drive in production. New controls have been designed which can easily be changed from dual to single place and back again. The fuel tank has been relocated to improve balance and ease of manufacture. Engine cooling problems have been addressed and the modified Mazda 13b rotary powerplant is now producing 157hp at 5500rpm in a detuned state. The engine has been running on 91 unleaded fuel consurning 18 litres per hour. Weight including gearbox, starter, radiator, alternator and pre-rotator drive is 146kgs.
Engine: Mazda 13B rotary, 157 hp