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Jetson One – Personal Electric Aerial Vehicle

jetsonaero.com

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Re: Jetson One – Personal Electric Aerial Vehicle

#171

Post by y4mi »

fragmede wrote: post #156
nikitaga wrote: post #121

If you're interested in the components, looks like both motors and propellers are from https://www.mad-motor.com It's quite hard to find high quality electric drive components in this size – too big for drones, too small for full scale airplanes. https://store.tmotor.com/ is another alternative.

Where do Tesla's motors fit in on that scale? They don't (afaik) wholesale them, but used drive units are purchasable.

Not in the same market, so it's too heavy.

It could handle the required rpm to create lift/takeoff (up to 18k according to their marketing material, it would probably overheat if you had that kind of rpm for an extended period of time though), but you'd probably need a cable to an energy source.

Re: Jetson One – Personal Electric Aerial Vehicle

#172

Post by lovemenot »

taneq wrote: post #97
nine_k wrote: post #7

I wonder why the rotors are positioned so low. Should a propeller get fractured, the splinters would hit the pilot's chest and neck. OTOH putting the propellers above would change the shape and thus the aesthetics seriously.

You see this in so many ridable multicopters and it always makes me cringe... the plane of rotation of a heavily loaded, high speed rotating part is not a healthy place to hang out. The shared plane of rotation of 8 of them is 8x as bad.

Worse than 8x as one prop can disintegrate into another, cascading into the pilot.

Re: Jetson One – Personal Electric Aerial Vehicle

#174

Post by SideburnsOfDoom »

mortenjorck wrote: post #54

From the video, it looks like this craft is limited to about 10 feet in altitude (certainly as high as I’d want to go, but I imagine their primary market at first is going to be thrill-seekers). And yet that’s really all you need for a lot of point-to-point transport, especially in rural areas (which I also imagine will be the only legal places to fly these for the foreseeable future).

It does not appear to be limited by the Wing-in-ground effect. This effect apparently tops out at approximately half the vehicle's wingspan; and they are above that.

https://en.wikipedia.org/wiki/Ground_effect_(aerodynamics)

Re: Jetson One – Personal Electric Aerial Vehicle

#175

Post by ramesh31 »

hwillis wrote: post #168
Jnr wrote: post #157

Lacks the safety features of airplanes (gliding) or helicopters (autorotation), has terrible rotor placement and small air time. I would advertise it as "your personal death machine". :) No amount of money would make me use that thing. EDIT: Ok, sorry, it says it has a parachute, but I still would not use it.

Electric motors can autorotate just fine: https://youtu.be/QADYnVeHQOQ You can't descend quite as slow as a normal engine because the motor has somewhat more friction at low RPM, even though it's similar to free-spinning at higher RPM. That makes for a rougher final approach but just as much glide distance and control. Small rotors will make it more of a hassle but should still be quite safe. Even if you do end up to…

>Even if you do end up touching down hard, there's way less angular momentum stored up and you wouldn't have the chaos of giant blades exploding.

That angular momentum is what allows autorotation to be possible. Theres zero chance a quadcopter blade could maintain enough energy to autorotate while carrying the weight of a person. The blades are also fixed pitch, which would make a landing flare impossible.

Re: Jetson One – Personal Electric Aerial Vehicle

#176

Post by KineticLensman »

ChrisMarshallNY wrote: post #161
Jnr wrote: post #157

Lacks the safety features of airplanes (gliding) or helicopters (autorotation), has terrible rotor placement and small air time. I would advertise it as "your personal death machine". :) No amount of money would make me use that thing. EDIT: Ok, sorry, it says it has a parachute, but I still would not use it.

Parachutes have a minimum altitude. For standard human chutes, that’s 300 feet (100 meters) or so. Not sure what the ceiling is on this. They don’t have footage of it going too high. You only need to fall 30 feet (10 m), to buy the farm. Less, in many cases (depending on how you fall, and onto what).

Yes. This is why paragliding from hills is more dangerous than regular parachuting from a plane. Your paraglider canopy can collapse due to bad wind or unexpected updrafts at say 40 feet from the ground and you slam into the ground before it recovers. In contrast, when a parachute malfunctions on a freefall deployment, you are often higher than 2000ft, and there is plenty of time to deploy a reserve, fix twisted lines, etc.

Re: Jetson One – Personal Electric Aerial Vehicle

#177

Post by ramesh31 »

rbanffy wrote: post #127
fastball wrote: post #79

Earlier quoted context omitted.

Well at 210 lbs you're either tall enough that you probably won't fit in this thing lengthwise or you are in fact overweight and losing a few lbs wouldn't hurt.

I have this problem with Lotus cars. They “fit like a glove”.

>They “fit like a glove”.

That's the whole point of a Lotus.

Re: Jetson One – Personal Electric Aerial Vehicle

#178

Post by maxcan »

nine_k wrote: post #7

I wonder why the rotors are positioned so low. Should a propeller get fractured, the splinters would hit the pilot's chest and neck. OTOH putting the propellers above would change the shape and thus the aesthetics seriously.

Not to mention that having the center of lift above the center of gravity gives you some dynamic stability for free. This approach is the opposite.

Re: Jetson One – Personal Electric Aerial Vehicle

#179

Post by HPsquared »

t0mas88 wrote: post #148
hef19898 wrote: post #138

Earlier quoted context omitted.

That depends under which class the aircraft will be certified, depsite it being electric I could image that it falls under the ultra-light class (I'd have to look up the exact Name under EASA so).

EASA doesn't have rules for ultra- and microlight aircraft, they're only in national regulations. So then it depends on what the country you're in decides. But even if you're allowed to fly with only minutes of fuel reserve. The big question is whether you should want to. When you're in a more basic aircraft, that didn't go through all the certification requirements that other aircraft go through, it would not be a g…

This also doesn't look like it can glide or autorotate, so if you run out of fuel it's pretty much guaranteed to crash.

Edit: I guess that eventuality is managed by the parachute system and a structure designed to handle the resulting "hard landing".

Re: Jetson One – Personal Electric Aerial Vehicle

#180

Post by unwind »

Cederfjard wrote: post #162
unwind wrote: post #126

I found this [1] article when I started googling the people in the company, I thought this quite from their CTO Tomasz Patan was fun: Vi vill inte att folk ska köpa vår produkt och krascha den direkt, så vi har sålt till välkända personer främst i USA som skulle få för mycket skit om de gjorde dumheter med den which translates to (note: native Swedish speaker, but not a certified translator): We don't want people to…

They may have updated the article since you wrote your comment, but as of when I’m reading it, it’s attributing that quote to Peter Ternström, the other founder and CEO.

Oh! Yeah, you're right ... probably my bad, apologies for mis-attributing. Can't edit my comment any longer.
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