CFD analysis of the tigerfish retractable float system on a DHC- Twin Otter

A Retractable Float System is being developed by Tigerfish Aviation as a retro fit to existing aircraft. The concept of the Retractable Float System is to fold the floats into a streamlined pannier under the main body of the aircraft in order to reduce the aerodynamic drag by an estimated 20% compared to current fixed float systems. The reduction in drag improves the performance of the aircraft and reduces its operating costs by reducing fuel consumption and increasing range. In this paper, a computational fluid dynamics analysis of a Retractable Float System is performed on the DHC Twin Otter Seaplane. Fluent is used to perform a 3D analysis to calculate the various forces on the aircraft. The clean aircraft and the aircraft with the float pack are modeled. A DHC Twin Otter equipped with a the Tigerfish Aviation Retractable Float Pack was found to have only 17% more drag than the clean aircraft, as compared to 45% more drag for a fixed float equipped DHC Twin Otter. © 2008 SAE International.