It is critical that the holes in the fuselage be cut to the correct size for the seals to hold. Many planes have been converted to the seals, or the large rear windows, and the work done "free hand". I've seen planes where the two windows were not the same size and planes with windows that were probably twice the area for the "large" windows. If the seal retained windows fit correctly, popping out should not be an issue. The windows are not formed, so if the material is too thick (and stiff) this may cause them to pop out, too.
If your fuselage cutouts are non standard, we can have the windows custom cut to fit. If the screw retained windows are drilled and installed correctly, cracking should not be an issue. John Cooper Skyport Services 518 797-3064 www.skyportservices.net
