Journal of Intelligent & Robotic Systems

, Volume 93, Issue 1–2, pp 367–384 | Cite as

Quantifying Risk of Ground Impact Fatalities for Small Unmanned Aircraft

  • Anders la Cour-HarboEmail author
Open Access


One of the major challenges of conducting operations of unmanned aircraft, especially operations beyond visual line-of-sight (BVLOS), is to make a realistic and sufficiently detailed risk assessment. An important part of such an assessment is to identify the risk of fatalities, preferably in a quantitative way since this allows for comparison with manned aviation to determine whether an equivalent level of safety is achievable. This work presents a method for quantifying the probability of fatalities resulting from an uncontrolled descent of an unmanned aircraft conducting a BVLOS flight. The method is based on a standard stochastic model, and employs a parameterized high fidelity ground impact distribution model that accounts for both aircraft specifications, parameter uncertainties, and wind. The method also samples the flight path to create an almost continuous quantification of the risk as a function of mission flight time. The methodology is exemplified with a 180 km flight in Danish airspace with a Penguin C aircraft.


Unmanned aircraft Aviation safety Stochastic modeling Ground impact Probability of fatality 



This work is supported by the BVLOS FastTrack project between the Danish Transport Construction and Housing Authority, University of Southern Denmark, Aalborg University, UAS Test Center Denmark, and Heliscope. We wish to thank the partners for providing information and data for this work.

A short version of this paper was presented in ICUAS 2017 [21].


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© Springer Nature B.V. 2018

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Authors and Affiliations

  1. 1.Aalborg UniversityAalborg EastDenmark

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