Having 36 individual motor driven fans does not make the propulsion safer or more reliable if there is some single point in the motor control/power system which if it fails would disable enough motors to cause loss of lift/control of the aircraft. Second, their claims of "simplicity" and "high redundancy" may be rather optimistic. CARGOLIFTER HINGE PLUSUnfortunately, there are quite a few practical issues with this concept that they do not seem to have fully resolved yet.įirst, relying solely on differential thrust produced by speed changes of (36?) small diameter fixed pitch rotors to provide satisfactory pitch/roll/yaw control authority, plus the required lift in hover, is a very inefficient approach for VTOL operation. Except it should be "the dreaded 36 motor approach". I hear it suffers from the dreaded 35 engine approach.(someone wants their computer cooling fans back).That's funny. Obviously that's before we've talked about controllability, failure tolerance, minimum reserves, and all that stuff. I'm not saying it will necessarily be successful or reach any of the advertised performance goals, but just from looking at the energy and mass budget, it doesn't seem to be quite out of the question. Then, with decent batteries, say between 150-300 Wh/kg, there really is a corner of the design space where this vehicle might just potentially be realizable. For some reasonable assumptions, I find it would need only a fraction of the T/O power (as one would have expected) again depending on assumptions, this could be 5-15% of the take-off power. Then, for cruise flight, power would obviously depend on the lift/drag ratio and on speed. That doesn't appear totally out of the question for me. I did a quick calculation based on comparison with known aircraft and found that if it had a mass of say 2 tons and the fans a diameter of 0.6m, depending on propeller efficiency, ground effect, and some more esoteric things, it should require between 700-1200kW total power let's say 25kW for each of those 36 engines. To lift off, those fans will need to create more lift than its mass, at least including ground effect. Mmmh, let's at least try and guesstimate if this thing has a chance.
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