An experimental electric plane built by Hungary’s Magnus Aircraft and Siemens crashed on Thursday near Budapest, killing the pilot and the passenger.
Earlier this year the pilot took me for a 15-minute flight in this model, called the Magnus eFusion. The electric motor and the entire propulsion system are supplied by Siemens.
“The pilot—who you were flying with—was a good friend of ours; he loved flying the electric aircraft,” says Gergely György Balázs, head of Siemens’s Budapest research outfit.
János B. (as his name has been given in the Hungarian press) was 61 years old. His passenger, Gábor K., was 41.
Siemens and the Hungarian authorities are each conducting investigations, and according to regulations there will be no announcements until the analysis is further along. Meanwhile, Siemens is grounding the plane.
A local news site report, translated by Google, reports that "The aircraft ignited during the crash, the flames were extinguished by professional firefighters in Pécs and Siklós within a few minutes...." However, AVWeb cites witnesses who saw the aircraft “maneuvering at low altitude before catching fire and crashing in a near vertical dive.”
If indeed the fire began in the air, and if the airplane was indeed a pure electric version of the eFusion, then one might speculate the problem could have started in the lithium-ion battery pack. Such batteries can undergo thermal runaway, in which one cell suddenly releases a lot of heat, causing neighboring cells to do the same in a chain reaction. Thermal runaway has plagued cellphones, laptops, and e-cigarettes.
Magnus and Siemens are also working on a version of the plane that uses a hybrid diesel-electric design, which had its maiden flight in April. However, from the wording of the statements of Siemens and Magnus Aircraft, it would appear that the crash involved a pure electric version of the plane.
The eFusion is a semiaerobatic plane, and aerobatics in general can be risky. Just six weeks ago an experienced aerobatic pilot was killed in a practice flight before an air show in China.