Construction of backstop. Originally intended for use in conjunction with one of the various apparatus used to simulate astronauts walking on the moon, this backstop was eventually used as a backdrop for the various aircraft crashworthiness studies. By 1972 the Lunar Landing Research Facility was no longer in use for its original purpose. The 23 story structure was swiftly modified to allow engineers to study the dynamics of aircraft crashes. The "backstop" with its painted grid has become a backdrop for films and videos of numerous crash tests.