According to the latest industry forecast studies, the Unmanned Aerial System (UAS) market volume is expected to reach 4.7 million units by 2020. The effect of an airborne collision between a UAS and a manned aircraft is a concern to the public and government officials at all levels. The primary goal of regulating UAS operations into the National Airspace System (NAS) is to assure an appropriate level of safety. Research is needed to define airborne hazard severity thresholds for collisions between unmanned and manned aircraft, or collisions with people on the ground. The results presented in this report and the technical volumes focus the initial effort on analyzing a small quadcopter and a small fixed-wing UAS configuration impacting on a typical commercial transport jet and a typical business jet aircraft. This research will help determine airworthiness requirements for unmanned aircraft based on their potential hazard severity to other, already certified, airspace users in the NAS. The resulting severity thresholds will be based on UAS characteristics (kinetic energy, structure, shape, materials, etc.) under credible encounter scenarios and will provide for test criteria used to evaluate applicable operational and airworthiness standards. UAS that meet test criteria based on thresholds for these characteristics may be approved for operations over or near people on the ground and may be certified as airworthy under different criteria than other UAS. Due to the complexity of the problem, full-scale test article availability, time and budget constraints, it was decided to conduct the R&D effort by using National Institute for Aviation Research (NIAR) physics based Finite Element (FE) modeling techniques based on the Building Block Approach. Conducting these type of impact studies by analysis provides better insight into the crashworthiness response of the target and the projectile. Damage evaluation criteria are proposed to quantify aircraft damage to the different impact scenarios summarized in this report. This research concluded that UAS impacts are likely to cause more damage than bird strikes for an equivalent initial kinetic energy. UAS impacts were generally associated with greater damage levels due to the hard-bodied mechanical construction of the UAS, with its components made of dense and rigid materials.
