A South Australian company is seeking funding for a patented retracting float system that it says can reduce drag by as much as 20% compared with traditional seaplanes.
Adelaide-based Tigerfish Aviation is working towards showing a full-size prototype of the Retracting Amphibious Pontoon Technology (RAPT) at the Oshkosh 2010 show on a small, modern aircraft such as an Eclipse 500 very light business jet or a Cirrus SR22 piston single.
RAPT has floats and wheels that retract and morph into a streamlined pannier below the fuselage. Drag is reduced by concealing the boat-like shape of the floats from the airstream, reducing surface area exposed. The system reduces drag on floatplanes by around 20%, resulting in a 20% improvement in fuel consumption, increased range, payload and speed, and reduced operating costs.
Initially the company is not targeting existing floatplanes for the retrofit, but believes the system will be suitable for a wide range of aircraft, ranging from sports aircraft to regional airliners. "There is a growing interest in seaplanes and this will logically extend over a range of market sectors," says director Saxon Rudduck, pointing to an amphibious version of the Pilatus PC-12 or a Beech King Air, for example. RAPT would cost about $400,000 compared with $300,000 to put fixed floats on a Cessna Caravan, he adds
Rudduck says the product is not limited to the commercial market, with interest from a large US defence contractor in conducting studies on airlifter aircraft and interest in special operations versions.
Early last year the company successfully demonstrated the feasibility of the system on a one-sixth scale Caravan model in flight trials from a dam in South Australia's Barossa Valley. The trials successfully demonstrated water take-off and in-flight deployment of the floats and confirmed the drag reduction and in-flight stability predictions, says Rudduck.
Tigerfish was granted a US patent in 2005, but has failed to take the system to market due to limited funding. It has previously received some South Australian government funding, local grants and support from the University of Adelaide.
Tigerfish is seeking stage one growth funding, in the region of $4 million, to cover 12-18 months from next February. "This will allow us to build up our team, develop markets and undertake a prototype installation on a light aircraft," says Rudduck. Tigerfish is talking to a number of potential technical partners, including a US prototype house, a European centre of excellence in carbonfibre and several aircraft manufacturers in the USA and Europe, he adds.
Seaplanes offer a great untapped potential to help solve the problem of the limitations of land airports in terms of congestion, says Rudduck. In addition, RAPT is "modern thinking applied to seaplanes".
Across trhe Atlantic in the US and Canada seaplanes regularly drop in on lakes, rivers and coasts among the boats and yachts. It’s not that unusual a way to travel. Mayor Bloomberg of New York City wants to see more commercial seaplane use of the Hudson and East River around Manhattan. It’s far from a done deal, but it’s been enough to stimulate interest in larger flying-boats. Tigerfish Aviation, an Australian company, confirmed that they had talks with the mayor’s officials in New York. The company's patented design, in which floats are deployed for landing and retracted in cruise flights, can cut drag by 20% over standard float-plane design. This would allow economical float-plane conversions for aircraft as large as the Bombardier Dash 8 with around 70 seats.