Bird Impact Resistant Analysis of the F-15E Production Transparency System

摘要

The F-15E production transparency system was tested for its ability to withstandbird impact during simulated low altitude missions. The system consisted of the monolithic stretched acrylic windshield and two-piece canopy. An F-15B test fuselage was modified to an F-15E configuration with a wide field-of-view Head Up Display (HUD) and an inert ACESII ejection system. The low altitude mission was simulated by impacting a stationary fuselage pitched at two degrees angle of attack. Five tests were conducted in which bird velocity, weight, and impact location were varied to determine transparency system response and crew survivability. The impact locations consisted of the center high quarter point for the windshield and the low center point for the canopy. Test 1 provided a baseline for acquiring deflection data with a 4-pound bird impact to the windshield at 426 knots; the transparency system remained structurally intact. The HUD was installed for Test 2 in which a 4-pound bird impacted the windshield at 427 knots; the windshield contacted the HUD combiner glass resulting in catastrophic structural failure of the acrylic panel. A second HUD was installed for Test 3 in which a 4-pound bird F-15, Birdstrike resistance, Windshield system, HUD, Transparency, Acrylic, Triangulation, Witness plate, Breaker bar, Combiner glass. impacted the windshield at 395 knots; the windshield contacted the HUD combiner glass but remained structurally intact. The canopy was impacted in Test 4 with a 4-pound bird at 496 knots; the canopy failed, the bird penetrated, and the witness plates sustained damage. Test 5 impacted the windshield with a 2-pound bird at 536 knots; the transparency system remained structurally intact.