Swiss Post Suspends Drone Delivery Trials Following Crash

Swiss Post has suspended its trials of a drone service used to relay lab samples after one of its drones crashed in Zurich near a group of playing children.

The agency has been trialling the service with Californian drone maker Matternet since the middle of last year, and as of January had carried out about 3,000 successful flights, IEEE Spectrum reported.

The drones are used to transfer lab samples between hospitals as an alternative to ground transportation.

But the tests have been suspended since May when a malfunction caused one of the drones to crash into a Zurich forest, Swiss Post said.

Parachute failure

The Matternet drones are designed to shut down if a problem occurs, deploying a parachute and descending to the ground while flashing warning lights and making a loud whistling noise.

But in the May crash the cord connecting the parachute to the drone caught on a sharp part of the machine and was severed, causing the device to plummet to the ground some 50 yards from a group of playing kindergarten children.  No one was injured.

The incident follows a crash on 25 January when the drone crashed into Lake Zurich following a short circuit that interrupted power to the drone’s GPS.  In that crash the parachute deployed correctly.

Swiss Post said it has asked Matternet to reinforce the parachute ropes with metal braiding, increase the number of ropes connecting the parachute to the drone and increase the volume of the whistle.

Trials continue

Matternet said it had never seen such a parachute failure take place in the past.

“A failure of the parachute system is a clear failure of our safely mechanisms and we are taking all the appropriate measures to address it,” the company said in a statement.  “We take the safety of our technology and operations extremely seriously.”

After the previous crash Matternet added a fully redundant GPS, compass and power system to its drones.

Swiss Post said it has also reduced the wind speed limits for the drones to about 20 percent lower than requirements imposed by the Federal Office of Civil Aviation.

The group said it plans to continue trialling drone deliveries.

Delivery systems using drones are being developed by a number of organisations around the world, including Amazon and Deutsche Post DHL.