Possible future for MR design!

[gtranquilla]

A friend heavily involved in Engineering R&D with a strong interest in MRs asked about a possible hybrid design for MRs...... most of us have thought about it looking for better solutions for heavy lift in conjunction with longer flight times.

I have seen a couple of Youtube videos from Russia or eastern Europe showing a hybrid Multicopter (gas driven rotary motor + 4 electric prop drives). The challenge is that the center thruster that provides the bulk of the lift creates a counter torque etc. But here is a center thruster that has no counter-torque...... http://www.popularmechanics.com/technology/aviation/news/rocket-racing-league-back-up. The racer is powered by a pressure-fed, liquid-oxygen-and-alcohol-fuel engine developed by Armadillo Aerospace. The conventional quadrocopter electric prop drives simply provide just enough lift to do that 3 axis control.......

This would follow the original NASA LEM - Lunar Excursion Module concept which ofcourse had to use vector thrusters well above their LOX center thruster....
For Multirotors this would start as a costly R&D project but the concept seems very sound......

Has anyone seen other hybrid designs?:shame:

 

[sixshooterstang]

Maybe it is just me but arent gas motors less controllable than electric and create less Watts per kg than electric? At least at our scale

 

[gtranquilla]

The linear thruster simply reduces the MR weight in flight to zero during a hover. The electric prop drives provide 90% of the control and are still driven by LiPos..... But in the hybrid the LiPos are much smaller because they are only needed for control, not lift. The energy density of LOX/alcohol linear thruster is much higher than electrochemistry energy, i.e., LiPo.

Maybe it is just me but arent gas motors less controllable than electric and create less Watts per kg than electric? At least at our scale