Risk Level Analysis for Hazard Area During Commercial Space Launch Oliver J. Bojorquez Department of Aerospace Engineering San Diego State University San Diego, CA, 92182-1308 obojorquez@sdsu.edu Jun Chen Department of Aerospace Engineering San Diego State University San Diego, CA, 92182-1308 jun.chen@sdsu.edu Abstract—Current method used for integrating space launch vehicles into National Airspace System (NAS) and reducing aircraft risks includes closing large air space areas to any air vehicles, known as hazard areas. Airspace regulations cause aircraft to reroute increasing flight distance, delays and over- all flight cost. Air space restriction area and time are based on profile risk factors of space vehicle launch. This paper describes a method to dynamically construct a risk level map of commercial space launch operations’ impact on nearby aircraft. The hazard area is divided into multiple sections, each section is also dynamically evaluated for a risk level, which is a comprehensive index considering the uncertain debris trajectory model and launch failure probabilities. This method provides a framework for modeling an optimal aircraft routing plan within a required risk level. Index Terms—Space launch, Risk analysis, Monte Carlo sim- ulation, Hazard area I. I NTRODUCTION To safely integrate space launch operations into air traffic flow and minimize the risk to aircraft from potential accidents, Federal Aviation Administration (FAA) creates blocks of space surrounding the trajectory of the space vehicle for an extended amount of time. These blocks serve as a temporary flight restriction area covering a vast range, from launch pad to an altitude of 30 nautical miles, prohibiting all air vehicles from crossing this restricted area. Aviation restriction is generally activated 7 hours prior to launch and stays in effect 30 minutes after launch [1]–[3]. These restricted areas force air traffic flow to reroute around hazard areas, resulting in delays, increased fuel consumption and over all operational cost per flight. Delayed flights not only increase the aircrafts operational cost (maintenance, fuel, crew, etc.) it also requires ground personnel, extra gates and other external needs necessary to maintain a reasonable traffic flow [1]. With increasing demands in space access for commercial and military purposes these restricted areas will inevitably become more frequent and cause a substantial impact on air traffic flow [4]. Typically flight delays caused by these restricted zones would have overall operational cost increase averaging out in thousands per flight [5]. According to Airlines for America in 2018 average estimated cost of aircraft delay was 74.20 dollars per minute plus additional cost due to external costs [6]: decrease in airline demand, ground labor, etc. The overall cost could reach billions annually. Therefore, an increase in space exploration also demands appropriate methods to maintain an efficient traffic flow. Beyond there is an increase demand in space launch op- erations, inevitably a steady increase in number of aircraft in airspace will also occur. Increase of number of aircraft in the airspace causes a linear overall cost increase. Air Route Traffic Control Centers (ARTCC) provides forecasts of projected increase of aircraft in the air space. These forecasts serve as a base to determine future requirements regarding facilities, equipment, manpower and other related services [7]. According to FAA aerospace Forecasts Fiscal Years 2019-2039 [4] projected increase in aircraft annually is 1.4 percent. This steady increase implies a larger number of aircraft impacted by hazard areas making traffic flow much more difficult to evaluate. To allocate the various air space and other sources to main- tain an efficient traffic flow, Traffic Flow Management (TFM) is an efficient tool used by FAA. This task is accomplished by using a system approach managed by traffic personnel to facilitate the flow. These personnel analyze knowledge sent to them by en route and terminal controllers as well as other programs such as miles in trail (MIT), ground delay programs (GDP), ground stop (GS) and others to coordinate efficiently in the decision-making process [8]. In addition to regulating traffic flow involving arriving and departing flights, traffic management over constrained regions in NAS requires rerouting around blocked regions. These regions are air space regions blocked due to severe weather or other events which historically have caused an influence on air traffic flow. Routes used around these spaces are validated by ARTCC, these collections of routes known as National Playbook intended to assist traffic flow personnel conducting decisions, for this paper the most relevant routes are those involving operations inside blocked areas. Although, TFM remains a complex area of study presented with several challenges ranging from human factors to soft- ware engineering, continuous research in this discipline has aided in obtaining more efficient traffic flow. However, the current method with deterministic forbidden area provides little flexibility for TFM on hazard area. As launch operation demands increase, the need for a more flexible and risk level