Test of drone deliveries challenged by poor weather

The test was not only about the flight itself but about the entire logistics chain. At Skellefteå Airport the plan was to manage parcels, reload and prepare the drone for flight. In Norsjö the focus was on receiving the goods safely and efficiently as well as carrying out battery replacement for continued operation.

The planned distance was 70 kilometers and would have been the longest route Katla Aero had completed to date. The flight time was estimated to be around 35 minutes.

Weather set limits and resulted in shorter flights

The biggest obstacle during the planned test days was the weather especially the low cloud base.

“We are restricted by the requirement that the distance between the ground and the underside of the clouds must be 150 meters and it only takes a small part of the route to have poor weather before it prevents us from completing all or the remainder of the flight” says Robin Appelblom drone pilot at Katla Aero.

A short flight was carried out on Monday and several attempts were made later in the week but each time the flight was stopped due to low cloud base. At most the drone reached roughly halfway to Norsjö. On Tuesday freezing rain occurred a weather phenomenon that poses a risk to all aviation and no flights were made at all. On the final day test flights were carried out in limited scope.

Permits planning and safety along the route

The test flight had been planned well in advance and required a permit from the Swedish Transport Agency to establish a specific airspace. Such a permit may take around seven weeks to obtain and an operational permit can take roughly six to ten months. These permits are needed for flights with drones of this size and when flying beyond the pilot’s visual line of sight.

As part of the safety planning eleven prepared emergency landing sites were identified along the route in this case turning areas on forest roads. The drone was also equipped with a parachute to handle emergency situations.

Ahead of the flights the team collaborated with other airspace actors including air traffic control at Skellefteå Airport and the air ambulance helicopter. The route was also reviewed with regard to elevation changes, towers, buildings, nature reserves, buffer zones and possible emergency landing sites.

Regulations stopped the flights

What ultimately prevented the flights was the regulation related to cloud base. The pilot therefore chose to turn back even though the drone would technically have been able to fly in the weather conditions that prevailed.

“This is about airspace rules and permits needing to allow unmanned flight above the cloud base in a safe manner in the future. If drones are not allowed to fly in poor weather it becomes difficult to carry out commercial transport in this way” says Henrik Littorin program manager at Arctic Aviation Hub.

Because the weather halted the flights not all parts of the test could be carried out such as measuring complete energy consumption or testing battery replacement and parcel reception at the destination. At the same time the days provided important insights.

“It is extremely important that we test things in real conditions. As the rules stand today the result was that we could not fly. But the key is to try again and develop new safe procedures” says Henrik Littorin.

Katla Aero also sees opportunities for future development.

“In the future we hope to be able to fly in cloud and in that way carry out flights that we were not able to perform this week. We will take the lessons learned over these days and work towards reducing the impact that weather has on flight operations going forward” says Michel Jansson Aircraft Software Engineer and Pilot at Katla Aero.

High marks for the test site

Despite the weather limitations both Robin Appelblom and Michel Jansson are positive about Skellefteå Droneport as a site for drone testing. They highlight its location near the city its elevation compared to surrounding buildings and that the facility is heated which supports the handling of batteries and other temperature sensitive equipment. Safety aspects are also mentioned for example that flights depart away from rather than crossing major roads.