Polycarbonate Severance System
Lynn Hilden, Ray Weiss
In an effort to prepare for the next generation aircraft canopies, McCormick Selph, Inc., embarked on an Internal Research and Development (IR&D) effort aimed at severing polycarbonate materials. The program focused on polycarbonates ranging in monolithic thickness from .25 up to and including .75 inch thick polycarbonate and laminates of polycarbonate and acrylic up to 1.00 inch thick. The program was a complete success. Various core loads and sheathing materials were used and characterized according to the load density versus the thickness of the target. We have repeatedly severed, made bends around corners, transferred detonation fronts at joints on the target and severed polycarbonate every time. Over 300 tests have been performed at temperatures from -70oF to 207oF. This severance capability has also been successfully demonstrated on 6 full-scale polycarbonate canopy transparencies, the last of which was a YF-22 transparency that was conditioned at +200oF. MSI has a long history of canopy fracturing and severance systems. Polycarbonate is just the next material to be defeated for safe and successful pilot ejections from disabled aircraft.
Download all of 2001 papers CLICK HERE (.PDF)
