First-of-its-kind drone field study evaluates urban airflow in downtown Montréal

- Montreal, Quebec

There's no denying the rising popularity of drone usage in today's world. From delivering goods to search-and-rescue operations, there are many unique ways a drone can help with a task.

However, when flying a drone in an urban environment, operators have to deal with the disturbed airflow around buildings, known as wakes, which tend to challenge drone stability. In collaboration with Transport Canada, experts in advanced air mobility from the Aerospace Research Centre at the National Research Council of Canada (NRC) are measuring how full-scale turbulence affects these aerial vehicles in order to help develop regulations and standards for safer drone use within Canada.

This complex field study using drones (also known as remotely piloted aircraft systems) in an urban environment was conducted under the NRC's Integrated Aerial Mobility program. It's the first-ever combined study to feature drone-mounted wind sensors, rooftop-mounted wind sensors and wind tunnel testing.

Six people stand on the rooftop of a high building on a sunny day with a drone on a stand on the ground in front of them and a city skyline in the background.

The team from the NRC, Transport Canada and InDro Robotics is conducting drone studies in downtown Montréal.

With the help of InDro Robotics, who piloted the drones, the NRC team flew its drone, equipped with 2 anemometers in downtown Montréal, above and between the Montréal General Hospital, the Centre hospitalier de l'Université de Montréal and Place Ville Marie's high-rise buildings to measure wind speed and turbulence. The rooftop access allowed the team to set up the anemometers for the drone flights so researchers could follow medical use-case routes within the urban environment. These test flights were the longest flights ever conducted in a downtown core in Canada, according to Transport Canada.

"Acquiring urban flow measurements by flying a small RPAS through the city gave the project real-world context beyond expectations," says Hali Barber, a research officer at the NRC. "The size of the test environment and realistic conditions like variable winds and visibility issues against the urban backdrop reinforced the importance of this work in establishing safe urban operational limits for RPAS."

The field study also served as a case study to evaluate the feasibility of flight operations between 2 points in an urban environment.

This project aims to provide knowledge on urban airflow, in other words, the specific atmospheric conditions caused by urban environments, such as strong wind gusts between tall buildings, and to help advance our understanding of the effects of turbulence on drone stability. The results will be compared with wind tunnel studies on a scaled model of Montréal, which indicate that the turbulent wakes of buildings within Canadian urban environments may pose a challenge when operating drones. These data will help Canadian small and medium-sized enterprises develop drone capabilities for the urban environment, which is both a new opportunity and challenge facing the industry.