qchen98
Well-Known Member
- Joined
- Oct 8, 2021
- Messages
- 263
Edit: Someone pointed out that it makes way more sense to use an electric propulsion system than pedaling, as even a small motor can put 2 - 3 times the voltage that an average cyclist can produce.
The goal is still the same - extend the glide ratio of an e-powered ultralight glider, so the glide performance can match the number of a high-performance unpowered glider.
Now the question is, whether a really small 1.5kw (120kv) motor is sufficient to turn something like a Super Floater into a high-performance machine like the 100,000 dollar Ruppert Archaeopteryx! (For a few hours at least).
You can always go for a larger motor (say 15kw), but a smaller motor is less expensive weight less (only 680g), require less electrical knowledge(if you can build an e-bike, you can build it too), draws far fewer amps and very easy on the BMS and battery (only 0.5c discharge rate at maximum thrust).
With a 4kw battery, you can use the full thrust for at least 2.5 hrs. You can use any prebuild e-bike battery as well.
Original post:
Could a light sailplane get any meaningful performance gain by the mean of a human-powered propeller?
Obviously, the goal here is not to make the aircraft self-launchable but to extend the L/D by a significant margin.
I remember seeing a video of a glider pilot catching thin rope mid-air by hand and sustained level-flight(perhaps), wouldn't that kind of "thrust" easily achievable by a feet-turned propller?
Edit: the glider might need a 10ft propeller to work - but hypothetically, would the thrust coming off that propeller increase the glide ratio of a carbon dragon(or similar design) from 1:21 to 1:40?
The goal is still the same - extend the glide ratio of an e-powered ultralight glider, so the glide performance can match the number of a high-performance unpowered glider.
Now the question is, whether a really small 1.5kw (120kv) motor is sufficient to turn something like a Super Floater into a high-performance machine like the 100,000 dollar Ruppert Archaeopteryx! (For a few hours at least).
You can always go for a larger motor (say 15kw), but a smaller motor is less expensive weight less (only 680g), require less electrical knowledge(if you can build an e-bike, you can build it too), draws far fewer amps and very easy on the BMS and battery (only 0.5c discharge rate at maximum thrust).
With a 4kw battery, you can use the full thrust for at least 2.5 hrs. You can use any prebuild e-bike battery as well.
Could a light sailplane get any meaningful performance gain by the mean of a human-powered propeller?
Obviously, the goal here is not to make the aircraft self-launchable but to extend the L/D by a significant margin.
I remember seeing a video of a glider pilot catching thin rope mid-air by hand and sustained level-flight(perhaps), wouldn't that kind of "thrust" easily achievable by a feet-turned propller?
Edit: the glider might need a 10ft propeller to work - but hypothetically, would the thrust coming off that propeller increase the glide ratio of a carbon dragon(or similar design) from 1:21 to 1:40?
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