I have a horrid feeling I've posted something like this before, but now cannot find it. Or perhaps I just dreamed it after one of the Intercalary's cheese and wine parties.
Person-carrying electric drones are perfectly possible and have been designed, built and tested - sometimes without fatalities. The main limitation, naturally, is the batteries - they need to be big to sustain flight for even a few minutes, and therefore they're heavy, which means you need more lift, which means bigger batteries... It's sort of like the rocket equation.
So, just run the thing off the mains, duh. Now, there are obviously a few issues with running a person-carrying drone off the mains. However, being able to drone around a 100m hemisphere (and who is to say that human creativity cannot produce an extension lead of that length?) would still be incredibly cool. Indeed, water-powered jet packs are popular, despite being hose-limited to perhaps 10 metres.
That's it, really. A human-carrying drone that plugs into the mains on a 100m lead. Oh, and an uninterruptible PSU to give you 20 seconds of landing time in the event of a power cut.-- MaxwellBuchanan, Jan 14 2019 Drone with Air-to-Ground Power Tether [xaviergisz, Jan 15 2019] PowerLine Drone Power Tether System https://www.riseabo...r-system-for-drones [xaviergisz, Jan 15 2019] Air_20Swimming [xenzag, Jan 15 2019] Petróczy-Kármán-Žurovec https://en.wikipedi...C3%A1n-%C5%BDurovecTheir PKZ-1 was a tethered electric human-carrying helicopter in 1918! Able to lift three men! Mentioned in my anno [notexactly, Jan 16 2019] Mains powered helecopters for pilot training are Baked.-- 8th of 7, Jan 14 2019 Link?-- MaxwellBuchanan, Jan 14 2019 Cicaré SVH-4 flight trainer was the closest I could find, but not mains powered. Ideal for people who get vertigo.-- not_morrison_rm, Jan 15 2019 A slightly different idea to this, but could you power a drone with a high-power laser from the ground?-- hippo, Jan 15 2019 //could you power a drone with a high-power laser//
I'm guessing a small camera-carrying drone uses at least a few hundred Watts, which is a fearsome amount of power. Add a factor of 4 for losses (or not, if your drone is steam-driven). I guess it's possible, but you really wouldn't want anything to get in the way of the beam.-- MaxwellBuchanan, Jan 15 2019 Re. the links, so it can be done for regular drones used for filming or inspection. But a man-carrying drone would be nice. Title amended to reflect this.-- MaxwellBuchanan, Jan 15 2019 But what if you wanted to use it to carry a woman?-- hippo, Jan 15 2019 I think the woman would have something to say about it.-- MaxwellBuchanan, Jan 15 2019 Not just something to say - refer to chapters 3, 4 and 5, "Coping with rejection", "First aid", and "In the hospital emergency room".-- 8th of 7, Jan 15 2019 See Air Swimming - link.-- xenzag, Jan 15 2019 Hang on, which "mains" are referring to 230v, 110v or that pathetic 100v in Japan?
Shirley no one want to get shown up by weedy electrons?-- not_morrison_rm, Jan 15 2019 Well, a man-carrying drone is probably going to be in the tens or hundreds of kW, so if you're running it on 110V you're going to need some pretty hefty cables, which means the drone has to be more powerful, which means...-- MaxwellBuchanan, Jan 15 2019 The version we've seen (actually seen, operating) uses (used) 415V 3-phase supplied through a high-flexibility cable - possibly a silicone rubber.
For 100kVA, that's only 80A per phase, which is fairly modest. Because there's no fuel, just the motor, that sort of power would lift a lightweight 2-seater airframe.-- 8th of 7, Jan 15 2019 Daft question...why not just send compressed air up a pipe to the heli-wotsit, sufficient to drive the rotors?
It could be done by A) a gear box driving the rotors [boring] or B) plumb it out further to the rotor tip nozzley-things which could remove toupees at a distance of 50m [not boring].-- not_morrison_rm, Jan 15 2019 Hmm. I would guess that a sufficiently robust air hose would be less flexible than a power cord.-- MaxwellBuchanan, Jan 15 2019 Compressed air's a very inefficient means of energy transfer. There's a huge thermal loss at the compression stage, and a risk of freezing at the motor.
It's fine for devices like air tools, or starter motors, which operate at high power on a very short duty cycle, but for a system required to operate at continuous full load it's not practical.
// plumb it out further to the rotor tip nozzley-things //
Tip-rotor designs, like the Fairey Rotodyne and others, have been tried - the main disadvantage is that they are horrendously noisy.-- 8th of 7, Jan 15 2019 Why not use a rigid telescopic arm to support everything, and then the rotors can just be for show?-- pocmloc, Jan 15 2019 3 Phase is the way to go* and aluminium might be preferable for the conductor in the tether-cable. The conductivity/weight and strength/weight both work for you there although fatigue should be a consideration.
I had an idea a while back of using an electric drone as a short term take-off thrust augmentation for conventional aircraft. Sort of an electric JATO that flies itself back after detaching. This might be a good way of doing that, particularly on an aircraft carrier where the distances are already short.
*that's true for everything though, really. So disappointing that none of the major manufacturers do an approved 3- phase phone charger.-- bs0u0155, Jan 15 2019 Or a mains-powered drone-carrying man.-- MaxwellBuchanan, Jan 15 2019 Or a mains-powered man carrying a drone. I'm sure Stross had a character using electricity instead of mitochondria. Don't ask me what his output was.-- not_morrison_rm, Jan 15 2019 How is it a drone if it carries a crew?
IIRC, one of the early flight pioneers had an electric plane that was tethered to a tower. I can't find that now, but I can find something even relevanter: A tethered electric human- carrying helicopter in 1918!! [link]-- notexactly, Jan 16 2019 //How is it a drone if it carries a crew? // That, [notexactly], is one of the great mysteries of the universe.-- MaxwellBuchanan, Jan 16 2019 //How is it a drone if it carries a crew?//
//one of the great mysteries of the universe//
To be a drone it must either be autonomous or controlled remotely, so clearly it isn't a drone if it has a crew, doesn't mean a drone can't carry cargo, people are often cargo.
People that are cargo are called "passengers".
Mystery solved.-- Skewed, Jan 16 2019 // People that are cargo are called "passengers". //
BA cabin crew used to call them "punters", whereas Lufthansa staff referred to them as "the cattle".
Of all the words and phrases used by airline employees to refer to those who use their services, oddly "esteemed and important client" is not included.-- 8th of 7, Jan 17 2019 random, halfbakery