Analysis of sonic boom propagation and population disturbance of hypersonic vehicle trajectories

Kurzfassung

With more hypersonic space planes and re-entry vehicles being developed in the future, the topic of sonic boom shocks has a large impact on the feasibility of routine operations due to their impact on the ground and general population. A shockwave’s sudden appearance can lead to adverse effects on the population such as being startled or experiencing sleep disturbances. Because some population overflight might be unavoidable, the sonic boom effect must be considered during the trajectory design. In this study, the trajectory design is combined with prediction methods on the sonic boom overpressure and area impact as well as the expected population response. By this, a novel approach is introduced that allows to consider the sonic boom influence already in the early design phase of a vehicle to avoid negatively impacting the population below. Trajectories of DLR’s hypersonic concept called SpaceLiner are analysed as primary reference. The trajectories are optimized to avoid population overflight along the whole flight track. These analyses show that the SpaceLiner is able to avoid dense population centres on most of the investigated routes, with the number of negatively impacted people staying below 10.000 for the majority of these. Additionally, the boom propagation is compared to reference trajectories of four vehicles in the development or concept stage: Starship, Dream Chaser, Space Rider, and Aurora. Because of their shorter re-entry profile, these vehicles generally impact less area than the SpaceLiner (1–2 million km2 instead of 2–7 million km2). This study advances the methodology in estimating the sonic boom overpressure in the early design phase of hypersonic vehicles and how this has an effect on the population and thus routine operations.