A Small All-Electric Helicopter Uses 7 Tail Rotors for Perfect Steering

The chopper can fly up to 27 minutes straight.

Fabienne Lang
A Small All-Electric Helicopter Uses 7 Tail Rotors for Perfect Steering
E-helicopter with seven electric tail rotorsOskarRDA/YouTube

It flies. It’s all-electric. It has seven electric tail rotors. It’s an all-electric helicopter. An inventor who goes by the name of OskarRDA on YouTube built and showcased an all-electric helicopter with seven tail rotors, and it’s impressive to see it in action. 

From super high-tech U.S. Army helicopters like the recently-unveiled Bell 360 Invictus to the world’s first manned hydrogen chopper, modern, flashy helicopters abound. So it’s fun and impressive to see DIY projects, like OskarRDA’s, literally take flight.

In one of his recent videos (embedded below), OskarRDA demonstrated his helicopter’s electric tail rotors in flight mode. The original tail rotor was a traditional drive-shaft one before he chose to switch it for the seven electric ones.

Each of the seven small tail rotors is individually powered by separate electric motors, reports TechEBlog. The helicopter only needs four 5008 or 5010 size motors with 18-inch props (45 cm) to deliver a thrust comparable to the traditional drive-shaft. Having the extra three help make the helicopter safer to fly; for example, if someone needed to autorotate safely to the ground after engine failure.

According to the blog post, the helicopter is an ultra-light Mosquito Air kit fitted with a two-stroke engine that OskarRDA turned electric using an EMRAX 228 109 kW brushless motor.

The helicopter’s battery capacity is 7.8kWh, which means that when hovering the power required is 21kW, so the battery will last 22 minutes. When flying just above 12.4 mph (20km/h) the power required is 17kW, so the battery lasts 27 minutes.