ICON Aircraft update
The first quarter of 2009 ICON continued to see a series of exciting successes–despite the challenging economic environment and uncertainty around us. Flight test recently completed high-performance water testing, sales passed position #400, and we continue to see unprecedented levels of market and media enthusiasm for sport flying overall and ICON in particular. Our recent customer survey results confirmed what we’ve suspected since our launch–there is indeed a huge, untapped market of non-pilots who are excited to join the aviation community if inspired by the right companies and products.
The A5 has been undergoing an extensive test flight regimen. While designing an “average aircraft” can be challenging enough, delivering a truly great aircraft requires an enormous amount of work. We recently completed a series of rigorous hydrostatic and hydrodynamic tests. These tests were designed to assess the basic hull performance for typical seaplane operations, as well as expand the envelope into higher winds and rougher sea states. Additionally, given that the A5 is designed to be a pure sport seaplane, it was engineered to handle more aggressive maneuvering on the water in order to make your experience safe while being extremely exciting.
With the combined efforts of some of the world’s top marine architects working side by side with ICON’s engineering team, the A5 may, in fact, have one of the most sophisticated seaplane hulls ever designed. Ironically, getting the hull performance of a seaplane dialed in is one of the harder tasks. So far, the A5 hull has far exceeded our expectations and is a star performer.
The details: The seawings on each side of the fuselage provide outstanding stability both hydrostatically and hydrodynamically. The seawings also provide robust, buoyant platforms for the users to move in and around the aircraft while on land or in the water. They also function like the swim platform on the back of a ski boat facilitating easy docking as well as easy access in and out of the water.
The hull’s forebody design achieves effortless “on-step” acceleration with little to no deck-angle change throughout transition from displacement to plowing to planing modes. There is minimal porpoising tendency. In fact, the A5 will smoothly and quickly accelerate onto the step to takeoff speed in a stick-free condition requiring little to no pilot input until rotation speed. The forebody’s higher deadrise allows the A5 to handle relatively rough water on takeoff and landing for such a small amphibian.
During step-turns (the first photo), the seawings allow the aircraft to bank significantly more than outrigger-type sponson floats that you see on typical hull-type seaplanes. This allows the A5 to make more coordinated, tighter turns on the water. The seawings are designed to engage the water and keep the wingtip from touching throughout the normal maneuvering envelope. However, the A5 also has planing wingtips that not only provide additional hydrostatic stability in extreme crosswind conditions, but are effective hydrodynamic planing surfaces should a wingtip contact the water in extreme or inadvertent conditions (the second photo).
The image below is an unusual sight–an aircraft in flight with its wingtip in the water. It was taken while testing the planing wingtip performance in extreme or “out of the envelope” situations. While the A5 is certainly not intended to be flown with the wingtip in the water, and is only being done here by a professional test pilot, the test successfully demonstrated the wingtips’ effectiveness and increased safety margins should such conditions ever be inadvertently encountered.
Going forward there are a number of areas still being meticulously refined on the A5, including gear installation, aerodynamic refinement and drag reduction of the hull, water-rudder improvements, and spray-pattern optimization. Stay tuned.