Helicopter Rotor Ice Shedding and Trajectory Analyses in Forward Flight

Abstract

Ice accretion on a helicopter’s aerodynamic surfaces during flight can lead to incidents and fatal accidents. An iced helicopter blade results in a decrease in stall angle, an increase in required torque, as well as potential damage from shed ice. While the high centrifugal forces on a rotor may serve as a natural deicing mechanism, they can also lead to uneven ice shedding, causing rotor imbalances or hitting other blades, the fuselage, or the tail rotor. Computational methods are important for predicting in-flight ice formation and are a vital tool in the design of ice protection systems. The objective of this paper is to present a computationally inexpensive methodology to determine for a helicopter in forward flight, following a period of ice accretion, rotor ice crack locations, shedding times, and potential impact zones.