Innovative Lightweight Onboard Aerodynamic Palliatives for Helicopter Brownout Dust Abatement

Rotorcraft brownout, which is caused by the entrainment of dust and ground debris by the rotorwash during take-off and landing, is a critical operational problem, and has caused a significant number of military helicopter accidents in Iraq and Afghanistan. Brownout affects safe operations due to the reduction of visibility, in addition to damaging engine components and rotor blades. Recent experience gained from operations in brownout with a variety of rotorcraft configurations, as well as ongoing work with validated analyses, indicates that aerodynamic modifications to the aircraft may offer a true solution to the brownout problem, at least in terms of pilot visibility. Therefore, the effort proposed herein seeks to develop innovative lightweight onboard aerodynamic solutions to brownout that can be retrofitted to current rotorcraft and incorporated into future designs without degrading performance or requiring additional onboard equipment or consumables. This effort will leverage work for the US Army developing physics-based analysis tools for the engineering simulation of rotorcraft brownout conditions and expertise in rotorcraft aerodynamic design, testing and performance analysis, to demonstrate that lightweight active aerodynamic solutions to brownout are not only viable, but also practical and cost effective without posing a risk to performance, operations or personnel.