Certified quality and optical propertiesBy the time Plexiglas gets in the air, it has already come a long way. It all begins at the Evonik plant in Weiterstadt, Germany, where the material is produced in a special casting process. Then, each Plexiglas sheet waiting to be delivered is certified in accordance with aviation standards. The aviation industry imposes high standards on acrylic in terms of optical quality, thickness tolerance, and mechanical properties. The material is then handed over to helicopter glazing specialists, Josef Weiss Plastic, to be processed further. The plastic is heated and stretched into the desired form. "This is crucial to ensure perfect visibility for the pilot," says Hornung. Each sheet is checked down to the last detail: Are there any optical defects in the material? Are the size and shape ok? Even a millimeter can make a difference. Every month, around seven sets of the finished glazing arrive at Eurocopter's German headquarters in Donauwörth. "If we order more material, it's usually here within three days," explains Hornung. Things soon start to get serious for the Plexiglas sheets. Air rescue missions place great demands on the materials.
Helicopters and their glazing have to withstand extreme changes in temperature, wind, and weather, as well as aggressive UV radiation.