Originally Posted by
riff_raff
Compare this to
a battery-electric 2 seat rotorcraft that was actually built and flown. It was a modified S-300C helicopter which already had a well developed rotor system and lightweight airframe. The electric motor was rated at 141 kW which was the same power produced by the original Lycoming piston engine. The lithium ion battery pack weighed 1100 pounds which was limited by the S-300C max GW capability . This allowed around 15 minutes of flight with a single pilot on board.
I'm sure the engineers that designed the Firefly were competent, and the motor/controls/battery were all based on current technology. So it would be fair to use the Firefly's demonstrated performance as a baseline to evaluate concepts like Lilium.
I don't believe the Firefly ever flew. Sorry for the response to an old post, I'm behind here.
I will say that anything will fly if you get the disk loading low enough. Asking about size and weight are entirely appropriate.