Building an electric fan jet for propusion while ice skating

We happened to have a 15 kW (20 HP) ducted fan left over from a project, and couldn't resist mounting it on a backpack to see how it behaved as a 'jet-pack' propulsion device for ice skating.

The electric fan is a Schubeler 215 EDF that can generate 25 kg of thrust while consuming 500 Amps. It runs at up to 14000 rpm, with an exhaust speed of 98 m/s (350 kph).
We drove the fan with a VESC 100/250 Controller and a Trampa battery box containing 84 Samsung 21700 Li-ion batteries each with a rating of 3.6V, 4 Ah, 35 Amps (1300 Wh total). A handheld remote was used to control the speed of the fan. The total weight of the backpack was around 20 kg.
We mounted it angled upwards so that that there was some lifting thrust to offset the weight, and so it would be easy to feather the propulsion by leaning back, whereas leaning forward gave maximum thrust.

The first test run in Uppsala, Sweden, went surprisingly well, reaching speeds of around 30 kph, but this was limited by the rather poor quality of the ice. It was clear that much higher speeds could be reached on good ice. After about 20 minutes of use, only about 10% of the battery capacity had been used.

The project was made possible with the support of ViruBustor AB, developers of systems for the continuous purification of air in vehicle cabins.

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(MRH homepage)