AOP
In Remembrance 2023
I just found my first crack in the L-4 windows. 300 hours since mounting. 1/16th inch Plexi. Left side, the first window aft of the sliding window, rear edge. It is between two mounting holes. NOT connected to either hole. It started at the mounting strip, where a small puddle of weld metal was deposited. It formed a bump and even though the window was loose, it still contacted the bump often enough through vibration that it started a crack extending away from the center in both directions. It spread under the trim strip and just recently became visible when it extended beyond the strip edge. I drilled both ends of the crack and dismounted the trim strip to find out where it came from. I also drilled out the contact point to relieve the pressure and hopefully it won't get any larger. You need to check any contact points where the glass is being repeatedly touched in one spot by something. It will look like a small cloudy spot in the glass, and may eventually form a crack.