An aircraft windshield’s sealant system is a critical element in windshield service life. The outboard moisture or weather seal (commonly referred to as the hump seal because of its appearance) protects against moisture ingress, which can cause delamination, interlayer degradation and damage to the windshield heating system. This seal also acts as an aerodynamic smoother and covers the outboard edge of the transparency. Because it is subjected to wind, rain erosion and UV exposure, the hump seal can degrade over time, making regular maintenance essential to maintaining windshield integrity and flight safety.
To address this challenge, PPG offers a comprehensive solution: the Hump Seal Repair Kit, designed specifically for commercial and general aviation aircraft.
What Is the Hump Seal Repair Kit?
The Hump Seal Repair Kit is a field-ready package designed for specific commercial and general aviation aircraft windshields. It contains everything needed to complete a hump seal repair on an installed windshield, including PR-1425 polysulfide sealant, a moisture seal forming tool tailored to the specific windshield model.
Adhesion promoter, tape, razor blades, gloves and the essentials for a complete repair.
Compact, easy to carry packaging ideal for line maintenance or minor hangar checks.
Why It Matters
The hump seal not only protects against moisture ingress but also serves as an aerodynamic smoother and a protective cover for the transparency’s outboard edge. Regular maintenance of this seal is vital to:
Prevent premature windshield failure
Avoid costly replacements
Maintain aircraft readiness
PPG recommends inspecting the moisture seal every four months or 1,000 flight hours, whichever comes first, for signs of erosion, degradation or cracking. Regular maintenance of the exterior hump seal is critical to preventing moisture ingress and helps extend transparency service life.
Designed for Efficiency
Whether you're servicing a commercial jet or a general aviation aircraft, the Hump Seal Repair Kit can help minimize downtime. Repairs can be completed overnight, making it a practical solution for operators looking to maintain fleet availability without extensive maintenance delays.
Part of a Complete Transparency Maintenance System
The Hump Seal Repair Kit is one of several specialized consumables offered by PPG’s Aerospace business to support the long-term performance of aircraft transparencies. Designed to restore the outboard moisture seal and help prevent costly windshield damage, the kit complements a full range of products engineered for cleaning, protection and visibility enhancement.
Other key transparency consumables in the PPG portfolio include:
PPG Tex-Whiz™ Aircraft Windshield Cleaner: A high-performance cleaning and polishing cloth, ideal for preparing transparency surfaces before sealant application.
CLARITY® Transparency Cleaning System: A dedicated cleaning solution formulated for aircraft transparencies.
HYDROSKIP® Advanced Coating Solution: A water-repellent coating that helps improve visibility in wet conditions.
SURFACE SEAL® Hydrophobic Coating: A long-lasting protective sealant that enhances durability and clarity
Together, these products form a comprehensive maintenance system that supports aircraft safety and helps reduce downtime and extend the life of transparency components. The Hump Seal Repair Kit plays a vital role in this system by enabling fast, field-ready repairs that help operators maintain optimal performance and compliance.
Learn More
To order Hump Seal Repair Kit or explore the full range of PPG transparencies consumables, buy now online.
