Is hard plastic or some form of plastic replacing glass in aircraft windshields? Any idea/companies/players in this field??
I have heard there is recent trend as plastics are light in weight and have properties comparable to that of glass.
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Sign up to join this communityIs hard plastic or some form of plastic replacing glass in aircraft windshields? Any idea/companies/players in this field??
I have heard there is recent trend as plastics are light in weight and have properties comparable to that of glass.
On light aircraft, acrylic windshields have been the norm. On higher speed aircraft, glass and laminates are used, particularly with heated windshields. The laminates may use polyvinyl butyral (PVB) is tough and ductile which enhances mechanical properties and impedes shattering of glass layers and the transmission of cracks from one layer to another.
Layered products may have various coatings which affect transmission of light and RF, reduce reflectivity, include elements for heating. While I do not know of an aircraft application, it is common in automotive for layers to include radio antennas.
Glass is an amorphous, non-crystalline material and acrylic plastics and glass have very different properties. Glass tends to shatter with sufficient impact. However, glass tends to have high resistance to temperatures that subsonic aircraft will normally encounter. Glass also retains good clarity properties over the operational domain of subsonic aircraft. Acrylic tends to be pretty shatter resistant, although I know a turkey vulture which proved otherwise (grin). Acrylic is more suspectable to abrasion and scratches, and therefore requires cleaning and maintenance considerations which glass does not.
It really depends upon the type of aircraft and the design criteria, which include the operations, temperature, heat requirements (ie hot windshield for de ice), weight considerations, EMI considerations (coatings, etc.) and so on.
Both materials have been in use for a long time.
So what kind of aircraft are you talking about?
A little late but I see some points the answers above missed and feel the record needs set straight.
Fixed wing military aircraft typically use thick polycarbonate plies laminated with polyurethane inter layer with various EMI coatings.
Military rotorcraft will use much thinner plies of polycarbonate, acrylic or a combination of both with various EMI coatings and extremely scratch resistant outer coatings to protect against all the debris they churn up.
Most commercial and general aviation aircraft have a glass outerply for scratch resistance, heated de-ice/de-fog capability, and static drain laminated to a main ply with polyurethane inter layer. The main ply is typically 2 plies of acrylic laminated with a type of vinyl interlayer. Some aircraft have polycarbonate main plies but acrylic is the norm. Plastic windshields/side panels are much lighter than all-glass windshields but are more difficult to manufacture. For that reason, some commercial/general aviation aircraft today are still designed with all glass windows, but it is a dying trend.
Major players in this field are Sierracin/Sylmar Corp (subsidiary of PPG Industries), GKN, Llamas Plastics, and Texstars