Commonly called a hump seal because of its appearance, this seal also acts as an aerodynamic smoother and covers the outboard edge of the transparency. An aircraft windshield’s sealant system is the most critical element in extending windshield service life. Because it is subject to the effects of wind and rain erosion and UV exposure, a hump seal can degrade over time. It is important to maintain the seal.

PPG makes it easy to repair a hump seal in the field with hump seal repair kits designed for windshields on commercial and general aviation aircrafts. The kits contain everything needed to repair a hump seal on a windshield, including PR-1425CF B 1/2 chromate-free* windshield sealant by PPG's aerospace business. Hump seal repairs can be done overnight on the line or during a minor maintenance check in the hangar. PPG recommends inspecting the windshield moisture seal every four months or every 1,000 flight hours, whichever occurs first, for signs of erosion, degradation or cracking.

Contact PPG to talk to our aerospace transparencies experts for more information or to purchase PPG hump seal repair kits