干旱区生态环境知识资源中心

Forward looking infrared windows on aircraft suffer damage from liquid and solid particle impact. Diamond is a suitable material for protective coatings on the geranium and zinc sulphide windows used for the 8-14 mu m waveband. The coating of small samples with diamond using microwave plasma assisted chemical vapour deposition has been report-ed previously, and that technology is being developed to coat fiats and domes to over 150mm in diameter. As a demonstrator, germanium windows for the Harrier GR7 and AV8-B FLIR systems have been diamond coated, and data on these windows is presented. This data includes optical performance in the 8-14 mu m wave band, and the issues of reduction of reflection and scattering losses are discussed.

The results of dust erosion and water jet impact testing are presented. The relation of the dust testing parameters to the conditions that military aircraft might be expected to experience in desert conditions will be discussed. At present, most dust/sand erosion tests appear too severe in terms of dust and sand particle size distributions at given velocities and altitudes.