Tiltrotor aircraft inlet-barrier filter method and apparatus

摘要

An inlet barrier filter system for a tiltrotor aircraft comprising a filter duct extending from a filter to a filter outlet, a ram air duct extending from a ram air inlet to an engine where the filter duct connects to the ram air duct at the filter outlet, and a closure member movable between a first position blocking the ram air duct and a second position blocking the filter outlet. In use, the inlet barrier filter system provides for two mutually exclusive air flow paths, one for introducing ram air to the engine while closing off the filter and another air flow path for introducing filtered air to the engine while closing off the ram air duct.