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Jetson One – Personal Electric Aerial Vehicle

jetsonaero.com

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Re: Jetson One – Personal Electric Aerial Vehicle

#231

Post by KineticLensman »

nikitaga wrote: post #196
KineticLensman wrote: post #176

Earlier quoted context omitted.

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 line…

What are you comparing, deaths per flight, per flight hour, per participant per year? Do you distinguish tourists, hobbyists, and competitors? What about injuries? Credible and reliable data for such comparisons does not exist, unfortunately. Paragliders who aren't idiots don't spend much time at 40ft AGL in weather conditions that can cause a collapse. And not every low altitude collapse is fatal. Spine compression…

Anecdata I know, but I parachuted for two years and paraglided for a year (before airbags were a thing). I saw more injuries in paragliding and people I know broke hips, twisted ankles and bashed into dry-stone walls (head saved by a helmet, which was itself destroyed). The broken hip was a club instructor who was caught out landing.

In my parachuting experience I saw only one really bad accident: in an accuracy contest, a guy who was going to miss the target by a few feet, reached out with his feet and landed on the base of his spine. Stretchered away.

My own skydiving parachute malfunction occurred on opening at approx 2500 ft. The bastard main failed to emerge and I deployed my front-mounted reserve. The act of flipping onto my back unjammed the main and for a moment I had two canopies opening. The main won and I spent half a minute pulling in the reserve canopy so I could see where the fuck where I was going.

I didn't get the shakes until about ten minutes after landing. The jumpmaster confirmed the sequence of events and I got back on the horse and jumped again 40 minutes later.

YMMV

Re: Jetson One – Personal Electric Aerial Vehicle

#232

Post by NovemberWhiskey »

brianwawok wrote: post #229
NovemberWhiskey wrote: post #227

Earlier quoted context omitted.

Can you provide a link to such a system? I did a best-efforts search and failed to turn up anything.

https://en.wikipedia.org/wiki/Ballistic_parachute

I'm unaware of any of those which are zero-zero. The Cirrus CAPS system has a minimum altitude of 400 ft or 920 ft after a one-turn spin, for example. BRS doesn't make specific claims for their system as far as I know but I'd be amazed if it were that much improved over the Cirrus one.

Re: Jetson One – Personal Electric Aerial Vehicle

#233

Post by yholio »

BurningFrog wrote: post #219
yholio wrote: post #183

It's a nice toy, but the problems of personal aerial vehicles were not about electric motors vs ICE: - Massive amount of sound pollution, current crop won't be allowed near cities in significant numbers; that's why the presentation videos are always silent. - Exceptionally energy inefficient and limited speed, due to the way lift is achieved; it makes zero sense to spend 10 times the energy to travel at speeds compar…

An air ambulance that flies above roads is actually a real good idea!

Airbulances are definitely a killer app. The loud noise is a feature, it makes people look up and make room for landing. A 0.005% chance of crashing on its built in airbags, and possibly damaging property or squishing somebody, while completely unacceptable for a personal recreation vehicle, would be ok for a device that can save a life every few flights. You can also find suitable infrastructure - helipads - on many urban hospitals.

Forget electric, it needs the highest density fuel system to allow at least an hour of flight, maybe a LPG fuel cell, or a piston engine geared with electromagnetic power couplers to the propellers for very rapid dynamic response.

A two person craft, lifting maybe 250Kg overall to allow for medical gear, the medic operates during liftoff/landing then autopilot takes you to predefined hospitals on predefined flight paths that are known to be safe.

This should be a thing already.

Re: Jetson One – Personal Electric Aerial Vehicle

#234

Post by obmelvin »

VLM wrote: post #202
ChrisMarshallNY wrote: post #161

Earlier quoted context omitted.

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).

> Parachutes have a minimum altitude. If you have the money, zero/zero ballistic parachutes have been a reliable thing for more than half a century. For ultralight sized aircraft, they cost about 1/5 the cost of a new airframe. Generally they don't provide much survivability IMHO. Most ultralight deaths seem to boil down to CFIT and similar "happened too fast too close to ground" incidents with a side dish of refusal…

> "happened too fast too close to ground"

The Jetson One video seemed to show them flying pretty close to the ground - I was wondering if that was to reduce fall height in the event of loss of power.

Your comment seems to indicate that one is sort of trading problems, not really significantly reducing risk (at least at the speeds one would want to go) - do I understand that correctly? Mind slightly expanding? Is the problem that you basically hit the ground with your full speed rather than having some wind resistance reduce your speed before impact?

Re: Jetson One – Personal Electric Aerial Vehicle

#235

Post by CryptoPunk »

gorgoiler wrote: post #230
CryptoPunk wrote: post #189

Earlier quoted context omitted.

Knee-jerk ascription of new product classes to elitism isn't constructive. The iPhone, when first released in 2007, cost $500, or about $800 today after adjusting for inflation, but launched a smartphone industry that today produces devices that are affordable enough that 3 billion own one, including some that go for as little as $50 and have better performance than the original iPhone.

Dude, it’s a helicopter .

It's a multicopter..

Re: Jetson One – Personal Electric Aerial Vehicle

#237

Post by nradov »

VLM wrote: post #200
t0mas88 wrote: post #131

Earlier quoted context omitted.

12 minutes endurance is absolute madness to any pilot. No way to fly this thing within the current regulations. A fuel powered aircraft needs to land with a legal minimum fuel reserve of 30 minutes when flying visually (good weather only), in worse weather it's 45 minutes + the time it takes to get to an alternate airport in case of problems at the destination. So usually 1 to 1.5 hour of reserve/alternate fuel on to…

Depends a lot on use case. I have some experience with visual inspection of aerial optical fiber. You can rent a very large and expensive helicopter to fly uncomfortably close to swaying fiber and power lines, or fly this thing up and down the line. There's also a lot of money in visual inspection of power lines. Not in California, LOL, where they just let it burn, but in better areas, when trees or vines get too clo…

A US Navy carrier strike group already always has a search-and-rescue helicopter airborne during flight operations. That has been standard procedure for years. They can respond to a crash in a matter of seconds.

Re: Jetson One – Personal Electric Aerial Vehicle

#238

Post by nradov »

yholio wrote: post #233
BurningFrog wrote: post #219

Earlier quoted context omitted.

An air ambulance that flies above roads is actually a real good idea!

Airbulances are definitely a killer app. The loud noise is a feature, it makes people look up and make room for landing. A 0.005% chance of crashing on its built in airbags, and possibly damaging property or squishing somebody, while completely unacceptable for a personal recreation vehicle, would be ok for a device that can save a life every few flights. You can also find suitable infrastructure - helipads - on many…

That's just silly and completely unrealistic. We already have helicopter ambulances. They work, but have a relatively high accident rate due to being called to fly frequently in bad weather and near obstructions (trees, power lines). The FAA and crew members won't tolerate something that's even more dangerous for domestic civilian use.

There are no such thing as predefined flight paths that are known to be safe, at least not in the areas where air ambulances have to operate. There is always a risk of collision with other aircraft operating under VFR. And a human pilot is always needed to cope with in-flight emergencies that autopilots can't handle.

There could be a limited use case for military casualty evacuation drones. The military is researching those for use in combat zones where sending a manned helicopter would be too risky.

https://taskandpurpose.com/gear-tech/army-drone-helicopter-m...

Re: Jetson One – Personal Electric Aerial Vehicle

#239

Post by nradov »

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…

That is dangerously incorrect. Successful autorotation requires high inertia rotor systems with controllable blade pitch. Small rotors like on this Jetson don't have anywhere near enough inertia, and it looks like they're running fixed pitch props. The type of motor is irrelevant as long as the motors can be de-clutched from the rotors.

Re: Jetson One – Personal Electric Aerial Vehicle

#240

Post by nradov »

pininja wrote: post #115
edrxty wrote: post #109

Earlier quoted context omitted.

I haven't heard of any deaths as a result but I'm sure there are a few. Usually it's just a hull loss. That said, this looks like another Icon A5 situation...

I don’t have great sources, so take my claim with a grain of salt. But overall this analysis of Cirrus incidents over 25 years [0] was interesting to read. In response to fatalities and pilots choosing not to use the parachute when that could have saved lives, Cirrus improved training and saw significant safety record improvements. > By then, Cirrus had already upgraded its training twice, eventually pulling it entir…

The new Garmin Autonomi system is designed so that a passenger can push one button to land the airplane if the pilot passes out.

https://discover.garmin.com/en-US/autonomi/

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