Australian Unveils Prototype Hoverbike

JSF01

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Well I see that I see a lot of people that seem to believe this design is unstable and think it would flip over. The truth is that assuming that this flies at all (the 10,000 feet 170 mph part no way in hell) it actually should be very stable assuming he designed it right. The ducted fans do a couple of things for the craft. The ducts can provide up to 60% of the lift which for craft like this is usually much needed. They also create a cool phenomenon when tilted the air flowing over the lower edge speed ups creating more lift, forcing the craft back up right. (It might be air flowing over the higher edge slows down creating less lift for that side but the end results are the same. It?s been a couple of years since I researched these types of craft.) Military testing during the 50's and early 60's proved that these designs are pretty much impossible to flip over.

http://youtu.be/GgNlumaVPDw

Don't know how to embed a video
 

remedyX

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Aerograt said:
Responding to what you said what I was saying is that it is possible to get a pilots license before you are seventeen/eighteen, here.

Why did you redact your post?
 

Agayek

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Oct 23, 2008
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Worgen said:
I suppose its plausible but until I see some good evidence for it Im going with fake, I dont see how a line of fans like that could really be stable anyway
It's theoretically possible for that arrangement to be stable, or so it appears. The fans are (as best I can tell without actual measurements) far enough apart and large enough in diameter to be mostly stable, barring sudden weight shifts and the like. I certainly wouldn't want to ride it on a windy day, but if it was clear, I could see the thing working.

I'm leaning towards fake myself, but that's more because his claims about flying at 10,000 ft seem a bit ludicrous. A single strong gust (and there's lots of those at that altitude) would almost certainly be enough to flip the stupid thing over and then you're fucked.
 

Agayek

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Oct 23, 2008
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EvolutionKills said:
Thank goodness. If all you needed was a motorcycle license or something, that would be terrible. Where I live, there are a TON of weekend warrior motorcyclists, and most of them can barely ride. They really easy to spot too. They all ride Harley-Davidson's, are decked out in leather chaps and vests, and usually don't wear helmets. Dead giveaways are when they hold in the clutch with their left hand at a stop light, and never shift the bike down into neutral. They just keep holding in the clutch, and roach their transmissions. Also, if you ever see somebody riding a bike with full leather gear, and wearing loafers...

A lot of these morons just get their permits renewed every year and never even bother to get a license. These people are bad enough on the ground, we don't need them in the air too. We already have flying assholes, they're called 'Seagulls'.
I'm not sure if you're being sarcastic or you simply misunderstood what you quoted, but the original post said you do not need a pilot's license to operate the thing. Matter of fact, since it's an ultralight, you don't need any license to be able to operate it.
 

mrverbal

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May 23, 2008
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just so you know: That wifi most of you are using to read this? Australian. Tanks? australian. Etc.

We welcome your thanks.
 

benvorbeck

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Mar 18, 2011
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Jewrean said:
Some awesome Australian inventions:
http://www.whitehat.com.au/australia/Inventions/InventionsA.html

If you can't be bothered reading it some inventions include:

- Refrigeration
- WiFi
- Pacemakers
- Google Maps
- Freestyle swimming
- Dual Flush toilets

EVERYONE! Stop being so pessimistic! Jeez! There have been fuckloads of dipshits like you in the world that have doubted inventions would work before their release! Have a bit of faith. I for one (like normal people should be) am excited for what the future holds. If this turns out to be a flop... so be it. If it turns out to be awesome... THEN AWESOME! But my point is for all you idiots screaming "FAKE!" or "PICS OR IT DIDN'T HAPPEN ROFL LMAO!" you guys are missing the whole point of intellectual and scientific discovery. Mistakes will be made. Our limits will be tested. But by god let the guy have his passion because it could turn out to be marvelous.

Erm... Google earth has penises in new zealand LOL just kidding

i fully agree with ur statement, the inventors who got us so far advanced today are not at all related to the unimaginative idiots screaming 'fake!' infact i think they might be related to the people burning women because they thought they were witches... you know, the pitchfork clan. this guy actually got outside and tried something instead of sitting behind a pc trying to point out what is fake or not
anyway, with my basic physics knowledge it looks bound to fail due to lack of counter thrust or balance, but atleast he can then take it further from there. who knows, they got those mallcop transporter thingies to balance
 

Niccolo

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Veloxe said:
Ya, it could exist in a working form. But 10,000 feet? 140 mph? I'm calling bullshit on that until otherwise proven that this machine works to those claims.
The funny thing is, the physics says that 140 mph isn't too hard to believe. The bike would effectively be skating along on a cushion of air - far, far less friction than a normal bike would face along the road (and rolling friction - ie, a tyre - is really low!) so 140 mph isn't totally unbelievable.

3 km into the air? Hahahano.
 

tsb247

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I'm not an aersoapce engineer (yet), but from what I have learned so far, this partuclar machine has a host of little life-threatening issues that would make it something to stay away from, that is, if it is in fact real.

The biggest problem I see is stability and control.

- Poor rolling characteristics due to longitudinal weight distribution.

- In the event of a single engine failure or loss of power, an unrecoverable pitching roll would result.

- The turning thrusters look as though they would provide for very slow turns. That's all well and good until a tight turn is needed, but this machine looks to be incapable of such things as a roll of 90 degrees or greater would likely result in a crash.

- Stall characteristics???? WHAT stall characteristics! There are ZERO lifting surfaces on this thing. Flying by propulsive force alone is a bad idea! I cannot stress this enough!

Ultralight or not, the FAA would never allow these in the skies.

I am also very skeptical of their claim that it can reach 10,000 feet.

This machine looks akin to balancing on a surfboard at 160mph and 120 feet off the ground. That is NOT my idea of safe!

There are reasons why airplanes evolved the way they did - with wings and tails. Sure, you can break from convention (see the B-2, X-36, and the V-22), but doing so creates new problems; some of which require complex solutions.

In fact, we can look to the V-22 as an example of how this machine is a bad idea. Let's take a look at the V-22.




This particular aircraft has a tilt-rotor design that allows it to transition between a helicopter and conventional airplane configuration. For the sake of this discussion, we will focus on it's engines in the helicopter configuration with respect to stability and control.

What do you imagine would happen if an engine on this aircraft were to fail or lose power while it is in it's, "Helicopter," mode? It would roll and crash.

Here is an example of what happened to the V-22 during early testing.


See any similarities???

The bike would likely suffer from the same stability issues due to its configuration.

The problems with the V-22 were (mostly) ironed out after a decade or so of rethinking the design and billions of dollars in R&D. Now, the V-22 compensates for engine failure or loss of power with a complex transmission system. In the event of an engine failure, a single engine is used to drive both rotors with a significant loss of performance.

DISCLAIMER: I do not know enough about the hoverbike to draw any specific conclusions. I have also not yet completed my AE degree. However, I have enough knowledge about what should fly and shouldn't (or shouldn't be allowed to) in order to draw my own conclusions and/or draw parallels to existing aircraft. There also may have been some things that I have overlooked. I put this together fairly quickly.
 

Kakashi on crack

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Aug 5, 2009
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briunj04 said:
Scientists still need to create hologram advertisements and automatic lacing shoes before I'm impressed (-_-)

Actually hologram technology has existed for a while now, it just sucks hardcore because its difficult to manage, and extremely expensive to produce on a mass scale.

And I thought that shoes without laces were automatic lacing shoes =D

OT: The way its designed, he'd have to lean forward to move forward, and assuming that's the case, its likely he'd easily be able to lean too far forward and it would flip on him due to the way the fans work. Overall its a system based solely on balance assuming its a real hover bike. It won't work anything like the old star wars ones.

I don't doubt it can reach 140 MPH if the fans move fast enough, but that will be going 140 MPH up, not forwards. If I'm correct. That or because of altitude and applying "airplane/helicoptor mechanics" it won't really be moving that fast, but will be going that far.

Also, sorry, but this is not real hover technology, its propeller based technology used in a new way. Think of it like a helicoptor for one person, but more dangerous.

The closest thing we have to a real hover technology is magnet-based tech that causes ojects to rise into the air due to opposite polarities.

... I want my reverse black hole repulsorlift tech. >.>
 

Unesh52

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May 27, 2010
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I'm calling bullshit. There's no way this thing is getting off the ground without immediately slamming into it. But...

 

tsb247

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JSF01 said:
Well I see that I see a lot of people that seem to believe this design is unstable and think it would flip over. The truth is that assuming that this flies at all (the 10,000 feet 170 mph part no way in hell) it actually should be very stable assuming he designed it right. The ducted fans do a couple of things for the craft. The ducts can provide up to 60% of the lift which for craft like this is usually much needed. They also create a cool phenomenon when tilted the air flowing over the lower edge speed ups creating more lift, forcing the craft back up right. (It might be air flowing over the higher edge slows down creating less lift for that side but the end results are the same. It?s been a couple of years since I researched these types of craft.) Military testing during the 50's and early 60's proved that these designs are pretty much impossible to flip over.

http://youtu.be/GgNlumaVPDw

Don't know how to embed a video
Ducted fans do not provide any, "Lift," by the true sense of the word. They are merely a means of generating thrust. That's it.

Lift is defined by the following equation:

L = (1/2)*ñ*(V^2)*S*(CL)

Where:

L = Lift (as a force)
ñ = Density of the fluid (air) **Should be lower case ro. It won't display correctly**
V = Velocity of the craft
S = Wing area
CL = Coefficient of lift from the given wing.

Lift is not generated without a lifting surface. That's all there is to it. What you are describing is propulsion. Propulsion =/= Lift.

Ducted fans are a nuscance when it comes to control. They are a means to provide directed thrust on command. There is very little more to them than that. The apparent stability comes from a gyroscopic effect due to the spinning of the blades. However, this can also cause control issues because they want to 'right' themselves. Most of the time though, those effects are minimal. If you tip one, it will go in the direction it is pointed.



I think you are thinking of what is known as, "Ground effect," in your explanation since many older ducted fan designs relied on this to function (except the X-22). Ground effect aircraft are a whole new aerodynamic can of worms as you then have to start worrying more about wingtip vortices and stranger airfoil shapes as well as more unusual wing design. I have not researched ground effect aircraft in depth, but here is a nifty visual describing it. It's essentially that, "cushioning," effect you see in many of the early test demonstrations that make the aircraft appear to be more stable that is really is.





As I stated in my previous post, flight based on propulsive force alone is a bad idea. If your propulsion system should lose power or fail, you are done for, and if the craft in question got more than 50 or so feet off of the ground, the ground effects would be lost and you would essentially be held up by engine thrust alone - NOT good.

EDIT: There should be a lower case ro in that equation. I had trouble making it display correctly.

EDIT 2: Edited for organization and better explanation
 

LorienvArden

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Feb 28, 2011
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From whats shown in the video, I call BS.

Compare the design to this:
http://www.youtube.com/watch?v=SHPedpE70Es&feature=player_embedded

from what I've seen on the homepage, I don't think this would work - even if it did, it would be quite uncomfortable to ride and steer.
 

Worgen

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Agayek said:
Worgen said:
I suppose its plausible but until I see some good evidence for it Im going with fake, I dont see how a line of fans like that could really be stable anyway
It's theoretically possible for that arrangement to be stable, or so it appears. The fans are (as best I can tell without actual measurements) far enough apart and large enough in diameter to be mostly stable, barring sudden weight shifts and the like. I certainly wouldn't want to ride it on a windy day, but if it was clear, I could see the thing working.

I'm leaning towards fake myself, but that's more because his claims about flying at 10,000 ft seem a bit ludicrous. A single strong gust (and there's lots of those at that altitude) would almost certainly be enough to flip the stupid thing over and then you're fucked.
not to mention that if you get over 7k feet you start to get into thin oxygen and too long there can mess you up. That lil thing doesn't look pressurized so its pointless to even say it can go that high
 

tsb247

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Worgen said:
Agayek said:
Worgen said:
I suppose its plausible but until I see some good evidence for it Im going with fake, I dont see how a line of fans like that could really be stable anyway
It's theoretically possible for that arrangement to be stable, or so it appears. The fans are (as best I can tell without actual measurements) far enough apart and large enough in diameter to be mostly stable, barring sudden weight shifts and the like. I certainly wouldn't want to ride it on a windy day, but if it was clear, I could see the thing working.

I'm leaning towards fake myself, but that's more because his claims about flying at 10,000 ft seem a bit ludicrous. A single strong gust (and there's lots of those at that altitude) would almost certainly be enough to flip the stupid thing over and then you're fucked.
not to mention that if you get over 7k feet you start to get into thin oxygen and too long there can mess you up. That lil thing doesn't look pressurized so its pointless to even say it can go that high
If I'm not mistaken, the maximum altitude that one can travel to using VFR and an unpressurized cabin is 12,000 feet. However, I could be mistaken. I'm not a pilot yet. either way, it would be freak'n COLD up there!
 

Worgen

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tsb247 said:
Worgen said:
Agayek said:
Worgen said:
I suppose its plausible but until I see some good evidence for it Im going with fake, I dont see how a line of fans like that could really be stable anyway
It's theoretically possible for that arrangement to be stable, or so it appears. The fans are (as best I can tell without actual measurements) far enough apart and large enough in diameter to be mostly stable, barring sudden weight shifts and the like. I certainly wouldn't want to ride it on a windy day, but if it was clear, I could see the thing working.

I'm leaning towards fake myself, but that's more because his claims about flying at 10,000 ft seem a bit ludicrous. A single strong gust (and there's lots of those at that altitude) would almost certainly be enough to flip the stupid thing over and then you're fucked.
not to mention that if you get over 7k feet you start to get into thin oxygen and too long there can mess you up. That lil thing doesn't look pressurized so its pointless to even say it can go that high
If I'm not mistaken, the maximum altitude that one can travel to using VFR and an unpressurized cabin is 12,000 feet. However, I could be mistaken. I'm not a pilot yet. either way, it would be freak'n COLD up there!
yeah I think 12000 is the max but anywhere over 7000 and if your up there for too long then you will start to suffer the effects of oxygen deprivation, and yeah it does get cold
 

whiteshark12

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Jan 30, 2011
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Total Thrust 295kg, off their website

yeah, i doubt this will really work, 300kg of thrust is considerable in a lateral direction, but not vertical. the actual bike is 105kg, so tough luck if you are over 18 or are relatively muscly/fat.
 

derelict

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Oct 25, 2009
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Well, it's not going to hit 170, or even 100 without a rear fan or rear ducted fan, and honestly it doesn't look like it's got enough control surfaces to fly straight and level in the first place.

I wouldn't hold my breath.

Worgen said:
yeah I think 12000 is the max but anywhere over 7000 and if your up there for too long then you will start to suffer the effects of oxygen deprivation, and yeah it does get cold
Gotta be higher than 7000. There's a bunch of places just here in the US that are over that, and the only real effect that's not related to baking is shortness of breath after exercise.
 

Twilight_guy

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Nov 24, 2008
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10000 feet? Using fans? Unless those fans are moving at the speed of light or so huge it makes the bike look comical or 10000 if he's dropped out of a plane I don't think that sounds real.