There's a few others, and in fact I considered doing this myself! But, I'd get bored of slowbelly 'flying' after about 15 minutes. I like to go fast.
I completely believe 40mins of flight time if you had actual resources to assign to this. Imagine using the 18650 as the frame and strapping motors to sticks, or other crazy ideas to bring weight down and time up.
Here's a guy who takes a 3" 1S quad, adapts an 18650 and gets 29 minutes of flight time: https://www.youtube.com/watch?v=BOZStU-QCSc
There's a few others, and in fact I considered doing this myself! But, I'd get bored of slowbelly 'flying' after about 15 minutes. I like to go fast.
I completely believe 40mins of flight time if you had actual resources to assign to this. Imagine using the 18650 as the frame and strapping motors to sticks, or other crazy ideas to bring weight down and time up.