Quantifying Weather Tolerance Criteria for Delivery Drones - A UK Case Study

As demand for final mile delivery has increased, the use of delivery drones is being explored in many countries, including the UK. Despite offering perceived benefits over existing methods in terms of delivery speed and reliability, there is little understanding of the design criteria needed for drones to actually realise them. This paper investigates how reliability and resilience of deliveries vary by transport mode, relating to the delivery success (i.e., can a delivery be made in a given time-window), and the flexibility of this success (i. e., how many different time windows are possible). Comparing the performance of current UK ground transport modes and drones using historic weather and reliability data, a review of the factors that contribute to what makes a reliable and weather resistant drone service is presented. Results suggested that a significant wind tolerance would be required to achieve a level of service equal to ground transportation, with VTOL platforms requiring tolerances ranging from 14 m/s ( Solent region), to more than 23 m/s (Scottish Hebrides). Fixed-wing platform tolerances were not as high, with a tolerance of 10 m/s achieving flights on almost all days in all case study areas. It is likely that some locations cannot reliably be served by drone and must depend on contingency options when flights are not possible. With significant variations in tolerance requirements, and notable seasonal variances, applications of delivery drones should be considered on a case-by-case basis, comparing to existing modes, to ensure reliable supply chains are realised.