A propeller blade 18 comprising a radially inner region 32 located between a blade root 28 and a portion along the blade length, a radially outer region 36 located between the portion and a blade tip 30, and a coating 40 at least along a leading edge 38 of the blade and radially inner and outer regions. The coating includes an icephobic material 48, wherein a first substrate portion 42 defines a first colour within the radially inner region and a second substrate portion 44 defines a second color 164 within the radially outer region. Optional substrate 46 may define a third colour 168. The coating may be transparent or semi-transparent and/or define a contrasting fourth colour. Wear or damage 166 of anti-icing coat 48 can reveal a substrate colour and/or a visual gradient of the colours indicating the wear level or extent. The coating cohesive coefficient may vary radially and increase with radius from the blade root. The radially outer region may be located where rotational forces are sufficient to remove ice from an uncoated blade. Alternatively, substrates 42, 44, 46 may be distinguished by electrical conduction, isolation, capacitance, magnetic strength, texture, etc.
Propeller blades having icephobic coating
2017-08-09
Patent
Electronic Resource
English