Determination of the collective risk in a case of a launch vehicle «Cyclon-4M» crash during the flight phase using polygon images to represent populated areas

1Gladkyi, EG
1Yangel Yuzhnoye State Design Office, Dnipro, Ukraine
Space Sci. & Technol. 2020, 26 ;(3):32-41
Publication Language: Russian
Safety confirmation during launches of contemporary launch vehicles (LV) requires the determination of the level of the
collective risk for the population along the flight route. The article considers two collective risk assessment procedures based on the representation of populated areas by convex polygons.
           Traditional procedures, used for determination of the collective risk for territories within the emergency LV fall area, divide the area into typical elementary figures – spherical squares of one-degree size along the latitude and longitude. The collective risk is determined for the squares, and then the total value is obtained for the whole territory. These elementary figures may signify administrative districts of various states with significantly different population density as well as unpopulated sea territories. Therefore, it is proposed to assess the collective risk directly for administrative districts of states (provinces, districts, regions, etc.), which lie within the emergency LV fall area. For calculations, these districts are represented as a convex polygon or totality of convex polygons that allow approximating the computational area of the populated territory to the reality and increasing the
adequacy of the proposed model.
           In the areas of emergency LV fall, the population is usually concentrated in settlements. The limitations of traditional approaches to the assessment of the collective risk for the settlements are shown for cases when emergency LV reaches the surface of the Earth without being destroyed and, consequently, the damaged area is comparable or exceeds the settlement’s housing territory. The presented procedure is based on the representation of the settlement’s housing territory as a polygon and the determination of the area of its intersection with the emergency LV damaged area. Statistical simulation is used to compute the collective risk.
            The practical usage of the proposed procedures is shown in the context of the Cyclone-4M space launch system developed in Ukraine.
Keywords: accident of launch vehicle on flight phase, collective risk, fall area, flight safety, launch vehicle
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