Beta

Slashdot: News for Nerds

×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Australian-Built Hoverbike Prepares For Takeoff

Soulskill posted more than 3 years ago | from the who-needs-a-jetpack dept.

Australia 200

Zothecula writes "Adventurous motorcyclists might be familiar with the thrill of getting airborne at the top of a rise, but the Hoverbike is set to take catching some air to a whole new level. With a 1170 cc 4-stroke engine delivering 80 kW driving two ducted propellers, the inventor of the Hoverbike, Chris Malloy, says with its high thrust to weight ratio, the Hoverbike should be able to reach an estimated height of more than 10,000 feet and reach an indicated airspeed of 150 knots (278 km/h or 173 mph). At the moment these are only theoretical figures as the Hoverbike hasn't been put through its paces yet, but Malloy has constructed a prototype Hoverbike and plans to conduct real world flight tests in a couple of months."

cancel ×

200 comments

Yeah, right.. (0)

Anonymous Coward | more than 3 years ago | (#36405296)

Why even post vaporware stories? totally pointless.

NUMBER 1 APPLICATION!? (2)

Jeremiah Cornelius (137) | more than 3 years ago | (#36405338)

Hoverbike Applications:

        Aerial Cattle mustering
        Search and Rescue...

why? (2)

Thud457 (234763) | more than 3 years ago | (#36405402)

more like "useless, but cool "
I hope somebody with money to burn backs these guys to get it to actually work.

Re:NUMBER 1 APPLICATION!? (1)

peragrin (659227) | more than 3 years ago | (#36405428)

S&R is possible, but flight time on that thing will be extremely limited. if it gets a full hour of flight time I would be impressed.

Military scout patrols might work, I could also see law enforcement uses to work with helicopters.

The big problem on ducted fan machines is fuel consumption. hey burn through too much of it just staying up.

Re:NUMBER 1 APPLICATION!? (2)

SnarfQuest (469614) | more than 3 years ago | (#36405572)

S&R is possible, but flight time on that thing will be extremely limited. if it gets a full hour of flight time I would be impressed.

What do you do if you are at 10,000 feet, and run out of gas?

Re:NUMBER 1 APPLICATION!? (1)

Deus.1.01 (946808) | more than 3 years ago | (#36405656)

Parachutes....no really that's his answer.

Re:NUMBER 1 APPLICATION!? (1)

Ruke (857276) | more than 3 years ago | (#36405670)

From the FAQ:

How safe is the Hoverbike?
* Very Safe. [. . .]
* Parachutes. [. . .]

Re:NUMBER 1 APPLICATION!? (1)

element-o.p. (939033) | more than 3 years ago | (#36405942)

Well...if it's like two of the three bikes I've owned, you switch to the reserve tank and hope the carburetor float bowl refills before you hit the ground. The third bike has a fuel gauge, which does wonders for preventing you from running out of gas.

Re:NUMBER 1 APPLICATION!? (2)

HTH NE1 (675604) | more than 3 years ago | (#36406320)

Galactica 1980 re-enactments.

Re:Yeah, right.. (0)

iamhassi (659463) | more than 3 years ago | (#36406252)

Apparently you're right, hoverbike is complete vaporware, there's not one video or photo of this thing more than 3 feet off the ground yet it's "able to reach an estimated height of more than 10,000 feet and reach an indicated airspeed of 150 knots (278 km/h or 173 mph)"

Only video they have is from February of smoke through the rotors [youtube.com] , so they know how to upload videos they just don't have any videos of this thing off the ground.

Videos coming soon: [hover-bike.com]
"We did hope to film the last test flight un-tethered, but unfortunately we needed to rebuild the propeller gearboxes due to unforeseen localized stress on a section of the mounting points"
READ It crashed

Come on gizmag, I'd expect better than this, I can attach giant propellers to a seat too, would you do a whole story on it?

I Know How the Advertisement Will Say... (0)

Anonymous Coward | more than 3 years ago | (#36405306)

Comes with own complementary casket!

Re:I Know How the Advertisement Will Say... (1)

Mister Whirly (964219) | more than 3 years ago | (#36405482)

Which is exactly what they said about the first motorcycles, cars, airplanes, helicopters, submarines, etc...

I mean who would want to ride in some loud mechanical contraption when the horse and buggy are still around?

This would be (2)

adeft (1805910) | more than 3 years ago | (#36405330)

The most epic race series. Get this thing running and get it running NOW!

PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

Jeremiah Cornelius (137) | more than 3 years ago | (#36405370)

With MAGIC!

What it needs is an anchor (0)

Anonymous Coward | more than 3 years ago | (#36405424)

After you start it up, you toss over to:

1. to lower the center of gravity.

2. keep you from taking-off.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (2)

SockPuppetOfTheWeek (1910282) | more than 3 years ago | (#36405504)

And rotational inertia.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

Deus.1.01 (946808) | more than 3 years ago | (#36405614)

I was thinking; "Surely, he must have some kind of computer between the stick and the engines."

http://www.hover-bike.com/faq.html [hover-bike.com]

Not a fucking word.

Unless someone can make this thing stabilize on its own in mid-air, its not worth a dime.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

Ruke (857276) | more than 3 years ago | (#36405692)

In the FAQ he states that the hoverbike "cannot autorotate." Do you think this is what he's talking about, or does that refer to something else?

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (2)

Score Whore (32328) | more than 3 years ago | (#36405858)

No that means that when the engine stops you plummet like a stone to earth. Unlike most helicopters which if they are unpowered and falling, the propellers will spin and provide some possibility of you not dying when you hit the ground. From wikipedia:

In helicopters and autogyros, autorotation refers to generation of lift by the main rotor when it is not being driven by an engine. Should an engine fail, a helicopter may be able to use autorotation lift to slow its descent and land in a controlled manner.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

Johnny Mnemonic (176043) | more than 3 years ago | (#36405876)

Does that actually ever work in practice?

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (2)

boristdog (133725) | more than 3 years ago | (#36405976)

Yep. Some pilots are so good they say "Watch this" when you're a mile from the landing zone and they shut off their engines.

Then they gently pilot the craft to the landing while everyone else inside pisses themselves.
Been there, done that.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

chuckugly (2030942) | more than 3 years ago | (#36405884)

Autorotation is the aviation term for the technique one should use in case a helicopter suffers an engine outage. It's the rotary wing equivalent of a glide.

really? (1)

Thud457 (234763) | more than 3 years ago | (#36405916)

you don't know what autorotate [lmgtfy.com] means in terms of helimacopters?!!!

"Cannot autorotate" means if you lose power to the rotors, you have no lift. ie, you plummet, rather than glide.

ESL (2)

Jeremiah Cornelius (137) | more than 3 years ago | (#36405704)

- Very safe. The hoverbike was designed with safety as the over-riding factor in all design. If you have ever flown and pre-flight checked a helicopter you will appreciate the simplicity of this design. With so many parts on a helicopter - and a large number of single parts that could alone cause catastrophic disaster if they should fail - it is just a matter of time. The hoverbike has as many components as possible with triple redundancy which requires at least 2 other components to fail before you might have a serious airborne failure. This combined with a massive reduction in total parts (compared to a helicopter) and the hoverbike becomes safer and cheaper.

- Parachutes. With the hoverbike you have the choice to wear an emergency parachute and have two explosive parachutes attached to the airframe, with a helicopter you have no such choice. The hoverbike in it's current configuration cannot autorotate (with adjustable pitch propellers it can) but this should not be viewed as a discredit to the design. Engine failure in a helicopter or plane by no means assures you that you will survive a autorotation or glide, as air crash statistics show. The option of removing yourself from the vehicle and descending via parachute to the ground may well save your life

- The propeller blades will have on the next revision (and certainly the final product sold) a fine mesh over the entire ducting, which will stop any wandering hands or large debri from entering the duct.

WAH! TRIPLE REDUNDANCY WITH FEWER PARTS! ZOMG!

THE OPTION OF REMOVING YOURSELF FROM THE VEHICLE!

I want the optional GIANT GYROSCOPE HELMET!

Re:ESL (1)

element-o.p. (939033) | more than 3 years ago | (#36406232)

TFA says two parachutes on the "airfarme" (sic -- I would presume the mean "airframe") and an optional parachute for the pilot. So you would have the "option" of removing yourself from the vehicle, but theoretically shouldn't need to. If you have an engine failure as well as a failure in two ballistic recovery chutes AND both the main and reserve chute that you are wearing, you are having a Seriously Bad Day.

Re:ESL (1)

Jeremiah Cornelius (137) | more than 3 years ago | (#36406318)

Tangle

Re:ESL (1)

Deus.1.01 (946808) | more than 3 years ago | (#36406334)

What makes you think you'd be in high enough altitude to make parachutes effective in the first place?

Re:ESL (1)

idontgno (624372) | more than 3 years ago | (#36406482)

Not a problem. Add a rocket-powered ejection seat. Oh, wait, not in an airframe with an unadorned saddle and a dry weight of 240 pounds. A modern zero-zero egress system probably weighs close to that by itself.

Jetpack?

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (0)

Anonymous Coward | more than 3 years ago | (#36405712)

I know it's unusual to RTFA, but...

But he initially wants to fine-tune the controls mechanically first to ensure he produces the most stable design. Eventually however, he says there will be room for a computer override of sorts to stop amateur pilots tipping over.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

Deus.1.01 (946808) | more than 3 years ago | (#36406214)

All the fine tuning in the world is not gonna help, the moment this thing gains some momentum not even Ace Rimmer could keep this from spinning out of control.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

element-o.p. (939033) | more than 3 years ago | (#36406188)

From TFA: "Malloy also says he plans to have the whole system controlled by gyros..." The wording could be a little clearer, but there it is.

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (1)

GameboyRMH (1153867) | more than 3 years ago | (#36406266)

The one thing I don't get is how do you control roll on this thing. The control surfaces under the ducted fans will give very little if any. If it goes upside down do you just pull the chute?

Re:PLEASE KEEP ME STABLE AND HORIZONTAL! (2)

Jeremiah Cornelius (137) | more than 3 years ago | (#36406356)

"This one goes like a bitch, carving up the road like a frenzied lesbian with a meathook"
-- Jeremy Clarkson, reviewing the new Mini in 2001 [wikia.com]

Breaking (0)

Metabolife (961249) | more than 3 years ago | (#36405392)

How exactly to they expect this thing to stop?

I see this scenario playing out:

1. Guy goes too fast on hoverbike
2. Kid runs after ball, runs in front of bike
3. Bike attempts to stop by adjusting pitch
4. Bike ends up becoming nearly upright
5. Kid looks at oncoming blades in horror

Re:Breaking (1)

Anonymous Coward | more than 3 years ago | (#36405410)

Or you could just turn? I bet you're one of those people that slams into the car in front of you with both lanes on either side wide open.

Re:Breaking (2)

Daniel_Staal (609844) | more than 3 years ago | (#36405420)

Why are you flying so low you can hit a kid anyway?

Re:Breaking (2)

xMrFishx (1956084) | more than 3 years ago | (#36405432)

Just rev up and give him a hair cut on the way over.

Re:Breaking (1)

Metabolife (961249) | more than 3 years ago | (#36405484)

Because the gov't isn't going to allow these things to fly unrestricted probably. It really should be called a helibike.

Re:Breaking (0)

Anonymous Coward | more than 3 years ago | (#36406024)

ultralite aircraft ... restricted by weight ... .no license necessary.

Re:Breaking (1)

jimrthy (893116) | more than 3 years ago | (#36406090)

It's getting classified as an ultralight, so riders won't need a pilot's license.

For whatever *that's* worth

Re:Breaking (4, Funny)

Nadaka (224565) | more than 3 years ago | (#36405896)

Why are you flying so low you can hit a kid anyway?

The kid is playing hover ball with his jet pack you insensitive clod.

Re:Breaking (1)

Anonymous Coward | more than 3 years ago | (#36405460)

Or you could, I dunno, stay more than 6 feet off the ground? With a 10k ft. limit, I don't think too many children are playing in the clouds.

Re:Breaking (3, Funny)

mandark1967 (630856) | more than 3 years ago | (#36405524)

How exactly to they expect this thing to stop?

I see this scenario playing out:

1. Guy goes too fast on hoverbike
2. Kid runs after ball, runs in front of bike, then realizes the guy is riding at least 50 ft above him, then he gets his ball
3. Bike makes no attempts to stop since it is far above the boy on the street
4. Bike passes kid harmlessly remaining upright and under control
5. Kid looks at oncoming car in horror
6. Mel Gibson runs over kid and yells, "You Abo scum will not grow up to sleep with me wife!

FIFY

Re:Breaking (1)

BJ_Covert_Action (1499847) | more than 3 years ago | (#36405540)

How many kids do you know that play with balls at 10,000 feet of altitude? Or did you even bother to read the summary?

Re:Breaking (1)

Deus.1.01 (946808) | more than 3 years ago | (#36405678)

About as many as the number of hoverbikes.

Re:Breaking (1)

Anonymous Coward | more than 3 years ago | (#36405644)

um.
1. Guy goes too fast on hoverbike
2. Kid runs after ball, runs in front of bike
3. Bike attempts to avoid kid by GOING UP IN THE AIR
4. Bike, having access to the third dimension, is not concerned with Kid or Ball.

Re:Breaking (1)

mangu (126918) | more than 3 years ago | (#36405734)

How exactly to they expect this thing to stop?

By hitting a tree.

Cool, but needs more guarding (1)

sl4shd0rk (755837) | more than 3 years ago | (#36405418)

I sure wouldn't want to faceplant into the cuisinart on the front of that thing.

Re:Cool, but needs more guarding (1)

xMrFishx (1956084) | more than 3 years ago | (#36405500)

if you ducked under it though, you'd be fine, if a little breezy.

Re:Cool, but needs more guarding (1)

blair1q (305137) | more than 3 years ago | (#36405684)

unless it lost lift

those blades probably keep turning even when it grinds you into salsa

to clarify (2, Insightful)

nimbius (983462) | more than 3 years ago | (#36405442)


# Airspeed Vne - 150 KIAS (untested)
# Hover (out of ground effect) - >10,000ft (estimated)

seriously slashdot, theres a difference between actual news and pure backyard bullshit.
anyone with even the most remote fucking grasp of physics and flight
should be comfortable debunking his claims as a complete lie.
most commercial helicopters stall out at anything greater than 8000ft; most of the ones flying around my city stick to around 600-800 ft ceilings..
The CH-47 Chinook twin rotor helicopter is used by the USAF to rescue climbers
on Mount Denali (McKinley) in AK. It can reach an altitude in excess of 19000 to land at an elevation of around 18000.
The biggest problem at that point is restarting the engines,
so a special storage device directs pure oxygen into the engine inlet to restart.

the highest altitude helicopter currently in existence is the AS350. A pilot named Didier Delsalle of France landed it on the summit of Mount
Everest (8,850 meters) in 2005...and the record is entirely speculative/disputed.

finally, A blackhawk military helicopter with a 1700 horsepower engine still only goes ~190 kias.

Re:to clarify (1, Informative)

Palmsie (1550787) | more than 3 years ago | (#36405518)

Meta rate garbage stories down next time. You're part of the community too ya know.

Re:to clarify (0)

Score Whore (32328) | more than 3 years ago | (#36405908)

Yes, watch slashdot externalize costs and internalize profits.

Re:to clarify (3, Insightful)

blair1q (305137) | more than 3 years ago | (#36405626)

Is your average helicopter ducted? No? Then its aerodynamics are not the aerodynamic comparison you're looking for.

This thing is a lot lighter than your average helo, and the ducting makes it more efficient in generating downforce.

Which isn't to say its claim of 10 Kft isn't an unsupportable guess. Just that your arguments are not sufficient to refute it.

Re:to clarify (0)

Anonymous Coward | more than 3 years ago | (#36406018)

Actually the ducting would make little difference, the maximum ceiling of a helicopter has to do with the rarity of the air at that altitude not allowing the rotors to provide sufficient lift. Ducting would increase thrust, but would enhance the rare air problem. I think a much more worrisome aspect of the design (as other posters indicate) is the lack of lateral inertia. The thing looks like a kayak, and we all know what they like to do, how'd you like to perform an Eskimo roll at x,000 feet up?:O
 

Re:to clarify (1)

blair1q (305137) | more than 3 years ago | (#36406080)

Think about that again. Ducting increases thrust at any given density. Hence more altitude, if your limiting factor is density.

Regardless, this thing will go nowhere useful without a roll stabilizer.

Re:to clarify (5, Insightful)

modecx (130548) | more than 3 years ago | (#36405676)

Because a UH-60 with a max takeoff weight of over 20,000lbs, and a sectional area of a school bus is at all comparable to a single-seater with a max takeoff weight of 600lbs.

In other news, scientists say a 600cc sportbike is faster than an unladen Freightliner tractor powered by a 600 horse Detroit Diesel. Who could have guessed.

Re:to clarify (1)

Anonymous Coward | more than 3 years ago | (#36405760)

The bike's counter-rotating rotar system is the same thing the Chinook uses which just might have something to do with its estimated altitude.
A blackhawk has a maximum speed of around 190 knots (218 mph ) and this bike is listed at 150 (173 mph) and with a differing weight of 231 lb from the bike to 11,000 lb to the blackhawk.

The guy admits the numbers are theoretical at this point as all of his tests have been carefully anchored to the ground as they are concerned with stability and control to this point.
FTA: '...Malloy works in the mechanical design of airborne and ground based hyperspectral sensors at an optical engineering company in Australia.'
It certainly sounds like his work has a good amount to do with the bike he's building so I'd say he has a better idea of its true capabilities than either of us do.

Surely these numbers will change as well probably lowering to more moderate numbers but that it works at all is pretty impressive.
According to the article he's planning tests where he is unanchored from the ground so we can see how well it works at the point or if he manages to make his bike and himself explode soon enough.

Re:to clarify (3)

Johnny Mnemonic (176043) | more than 3 years ago | (#36405856)


anyone with even the most remote fucking grasp of physics

You used 0 physics to rebuke his claim. You only supported your argument with non-analogous airframes.

I don't know if getting to 10K feet is possible with this thing, and I suspect it isn't--it wouldn't be matter of just air density, but also the rider would need protection, like air and temperature controls. Also the horizontal wind speeds would be a whole different factor, and it's not clear that he's taken those into account.

But shit, if it can fly stably at 30 feet at 50 mph that would be good enough for me. I could get off the roads, and therefore avoid traffic and use line of sight to travel.

Re:to clarify (0)

Anonymous Coward | more than 3 years ago | (#36406078)

No forced induction for the engine either. The designer doesn't seem to be aware of the 30% power loss at 10k feet, in addition to the reduced propeller efficiency.

The hoverbike in it's current configuration cannot autorotate (with adjustable pitch propellers it can) but this should not be viewed as a discredit to the design

Auto-rotate with a ducted fan? Not likely.

Finally, contrary to the FAQ, this(as described) is not legal in the US as an ultralight. Those cannot exceed 55 knots and cannot carry more than 18 liters of fuel.

Looks like fun otherwise. I just hate exaggerated/unsubstantiated claims by inventors, particularly when they are asking for money.

Stabil? (0)

Anonymous Coward | more than 3 years ago | (#36405454)

How in the world is it flight stabilized? It looks to me like there's nothing keeping it from flipping sideways and pile-driving into the ground. If the center of gravity was lower or there was some advanced computer controller system I could see it working quite well but without that I'm a bit dubious as to its ability to stay off the ground and/or keep the "rider" alive for long.

Re:Stabil? (1)

Jeremiah Cornelius (137) | more than 3 years ago | (#36405560)

Exactly. All stable, multi-fans have triangle or quadrangle arrangement to create a stable platform.

http://www.youtube.com/watch?v=bxktEwqxbC0 [youtube.com]

Draw a triangle on paper. Next, draw a square.

Very good. Now, draw a line.

If the problem doesn't leap out at you immediately, you are lacking in the ability to perform some very basic assessments.

Re:Stabil? (1)

bragr (1612015) | more than 3 years ago | (#36405786)

To compound this problem, I don't seen any way to direct airflow sideways in the design.

Re:Stabil? (0)

Anonymous Coward | more than 3 years ago | (#36405654)

How in the world is it flight stabilized? It looks to me like there's nothing keeping it from flipping sideways and pile-driving into the ground.

Good question. Why don't Chinook helicopters flip sideways and pile-drive into the ground?

Re:Stabil? (1)

idontgno (624372) | more than 3 years ago | (#36406054)

60-foot rotor span. [ch47.org] And a 15-foot fuselage width. And the center of gravity several feet below the rotor plane.

In comparison, with the Hoverbike, "Contrary to popular belief, having greater mass above the centre of pressure does not mean an unstable craft (yes it is less inherently stable than below)." [hover-bike.com]

Or, in the immortal words, "one of these things is not like the other."

I expect that the Hoverbike is has about the same static lateral stability as a real bike: not very much. I suppose you could market it as "relaxed aerodynamic stability [wikipedia.org] ", although without fly-by-wire and computer stabilization, it doesn't sound like it'd be much fun to ride.

Re:Stabil? (1)

GameboyRMH (1153867) | more than 3 years ago | (#36406406)

Or more importantly, the Chinook has swash plates, so the rotors themselves can roll the aircraft.

But does it work on water? (1)

mfnickster (182520) | more than 3 years ago | (#36405472)

In case I'm being chased by a thug with a meat tenderizer on his head.

Flight Stability (1)

Anonymous Coward | more than 3 years ago | (#36405480)

This thing seems like it would be unstable in roll, with the thrust apparently happening at or below the cg height of the vehicle. There might be some gyroscopic stability but I doubt that is enough for the vehicle to be safe under gusts or even manuevering, even though the guy claims some marginal instability is ok in the FAQ (what is the time to double a disturbance in roll attitude for this setup?). For what it's worth, I'm a fourth year aerospace engineering student.

Re:Flight Stability (0)

Anonymous Coward | more than 3 years ago | (#36405824)

He says in the FAQ he's looking for aerospace people -- give him a hand! :p

Great way to beat automatic photo speed traps... (1)

CCarrot (1562079) | more than 3 years ago | (#36405492)

...although the manned ones would probably still get you.

I don't know how they'd catch you, though...

Pure BS (1)

psyque (1234612) | more than 3 years ago | (#36405522)

How would he maintain lateral stability in that thing? Flap his arms? Looks like it would roll over as soon as you gun it. There doesn't appear to be any engineering to take that into account. What is this guys hoping this thing will fly on, hopes and prayers?

Aaah.... (3, Funny)

roc97007 (608802) | more than 3 years ago | (#36405532)

So there's my flying car. About damned time.

Re:Aaah.... (1)

SnarfQuest (469614) | more than 3 years ago | (#36405646)

This isn't a car! I want my flying CAR, with a trunk to haul anyone I run over!

Darwin Awards (1)

Jagungal (36053) | more than 3 years ago | (#36405568)

When I look at the design, its lack of stability and a rider sitting above the fan, only one thing comes to mind - what a perfect candidate for the darwin awards.

Re:Darwin Awards (0)

Anonymous Coward | more than 3 years ago | (#36405836)

Though it does look like it should be exceedingly unstable, especially when leaning to either side, apparently stability is a major concern of the designer.
FTA: 'With safety an obvious concern for airborne vehicles, Malloy says he has given as many components as possible triple redundancy and made the Hoverbike design as simple as possible.'

At this point it sounds like not everything that is planned to put in for stability and safety is in yet.
Also FTA: 'The propellers, which are currently largely exposed, will also be fully covered in a mesh to ensure limbs don't get too near the blades.'
Currently with each propeller having half of it not covered by mesh (the half furthest from the seat), it is still quite dangerous and similar thoughts to yours entered my head, too.

Re:Darwin Awards (0)

Anonymous Coward | more than 3 years ago | (#36406362)

+5 darwin award, unbalanced design

Lack of backup (3, Insightful)

bragr (1612015) | more than 3 years ago | (#36405594)

Airplanes have to ability to glide to an extent, helicopters can auto-rotate. I seriously doubt that the rotors on this are big enough to auto-rotate, or that the designer made the calculations necessarily in order to design something that can auto-rotate.

You could use a parachute but parachutes take time to deploy and slow your decent so while effective at higher altitudes, at lower altitudes, like say the altitude at which you would be herding cattle, an engine failure would leave you heading towards the ground without enough time to deploy the chute.

I'd fly this is there were 2 engines such that one engine could power both fans, and 1 engine had enough power to at least hover and make a safe decent. Even then, I'd still probably bring a parachute.

Re:Lack of backup (1)

drinkypoo (153816) | more than 3 years ago | (#36406004)

Sounds like it will be most dangerous at the same place as normal helis, low altitude. At high altitudes you can have high confidence that you will have time to ditch and pop your chute.

Do trolls always run from simple questions? (-1)

Anonymous Coward | more than 3 years ago | (#36406162)

http://tech.slashdot.org/comments.pl?sid=2225174&cid=36390518 [slashdot.org] Yes, it appears they do, don't they, drinkypoo?

This story works as concept art (1)

metrometro (1092237) | more than 3 years ago | (#36405640)

It's a beautiful piece of kit. If this were a Deviant Art sculpture project, I'd be in. The fact that these jokers think it'll actually FLY makes it better.

Looking forward to more tests. I also think this thing will kill a lot of pilots. But whatever.

Blade depth is rubbish? (1)

Twinbee (767046) | more than 3 years ago | (#36405710)

Why don't the blades have a deeper pitch/depth to them. From what I've heard, this increases the efficiency of the wind sucked underneath.

It's the same with cooling fans. Manufacturers (apart from the previous few) always make the blades super thin. It's really dumb, and it causes them to be much louder and waste more energy. Compare:

http://www.skytopia.com/stuff/fan.jpg [skytopia.com]

Re:Blade depth is rubbish? (1)

Amouth (879122) | more than 3 years ago | (#36406094)

that deep pitch is the cup.. and while it allows for more thrust at lower RPM it limits your max RPM which limits your max throughput. it can also cause disturbance behind the blade which can cause cavitation at higher RPM

Re:Blade depth is rubbish? (2)

Gubbe (705219) | more than 3 years ago | (#36406272)

For hover applications where the air doesn't need to be moved fast, maximum rotor diameter is always the best, because it lets you move the blades relatively slowly, avoiding parasitic drag (air friction) while still moving a lot of air. That's why helicopters have such big rotors. With this hoverbike, practical matters dictate that the prop diameter is very limited, meaning that in order to move enough air, you need to spin the blades really fast. In order to not waste all energy on air friction, the blades need to be very slim and low-drag.
Think of the wings of a jumbo-jet. At low speeds for landing, slats and flaps are extended to make a big curved wing. It creates more lift, but it's inefficient. It wastes much more of the kinetic and potential energy of the plane, slowing it down. At cruise speeds the slats and flaps are retracted, making the wing very streamlined and giving it maximum efficiency.
Finally, there's the pitch or steepness of the propeller. The propeller has the lowest drag when cutting the air at zero angle. Of course at that point it doesn't generate any lift either, so the efficiency sucks. When the angle is increased, the prop starts pushing air and creating an equivalent induced drag. The propeller is still almost parallel to the air, so the parasitic drag remains small. Since most of the drag is induced drag at that point, the efficiency is high. If the pitch is increased further, the propeller cross-section against the air increases and parasitic drag goes higher. Sure, it pushes air faster when spinning at the same speed, but since the parasitic drag is high, it can't be spun as fast anymore. High-pitch propellers are used in fast planes, because when the planes move quickly through stationary air, the effective angle of attack of the propeller (the angle at which the forward-moving prop meets the non-moving air) decreases, making it efficient again! In hover applications the prop doesn't move forward through the air at anywhere near those speeds so it's most efficient to use a low angle that provides the optimum lift and minimum drag.

A Long way to go (0)

Anonymous Coward | more than 3 years ago | (#36405758)

If you check out the Martin Jetpack (http://martinjetpack.com) you will see what this could become, but you'll quickly realise the co$t of getting this from a concept to a practical solution is very expensive. Aviation is an expensive business, and safety issues will dominate. Martin spent 25+ years getting the technology right, and only this year went untethered to 5000ft - and that was with a crash test dummy, and the thing flown by remote control, and also testing the ballistic parachute.

Anything so reliant on the pilot's ability to maintain stable control, will require a sophisticated (computerised) flight control system to keep it safe, and this device looks to be a wee way off that yet. Imagine some Aussie musterer 'hoovering" along at some fantastic speed, and belching after his aussie beer revisited his gills .... could make the keystone cops look somewhat boring.

There might be regulatory issues in the U.S. (1)

idontgno (624372) | more than 3 years ago | (#36405780)

From the FAQ:

Having previous experience in a helicopter or plane would be a great help. That said, this is a new way to fly and one would need to learn to ride the hoverbike in much the same manner as a helicopter or riding a motorcycle. If you live in the USA or your country has similar civil aviation regulations, then the hoverbike will be classed as a 'ultralite' which means you do not need a pilots license to fly the hoverbike.

From the summary of vehicle regulations for ultralight aircraft at http://www.ultralightflying.com/ultralight-vehicle-regulations/ultralight-vehicle-regulations.html [ultralightflying.com] :

FAA describes a powered ultralight vehicle as a vehicle that:

* Is used or intended to be used for manned operation in the air by a single occupant (through exemptions, FAA allows 2-place ultralights to be used for instruction only - see below);

* Is used or intended to be used for recreation or sport purposes only;

* Does not have any U.S. or foreign airworthiness certificate; and:

Single-Place

* Weighs less than 254 pounds empty weight, excluding floats and safety devices which are intended for deployment in a potentially catastrophic situation;

* Has a fuel capacity not exceeding 5 U.S. gallons;

* Is not capable of more than 55 knots (63 mph) calibrated airspeed at full power in level flight; and

* Has a power-off stall speed which does not exceed 24 knots (28 mph) calibrated airspeed.

The two items I've emphasized above in bold conflict with current specifications [hover-bike.com] of the prototype: A 30 litre fuel tank and a 150 knots indicated airspeed max. And, the dry weight (105kg) is skirting perilously close to the maximum permissible dry weight of an FAA ultralight, too. They can't afford to add 10kg to the weight of the prototype before going production, or it busts that standard too, and if they're going to a more robust prop design or a bigger engine, it could happen.

And, btw, anyone care to speculate what the power-off stall speed of a direct-lift non-autorotating rotary wing aircraft might be?

So, no, if nothing else changes, the FAA will not accept the Hoverbike as an ultralight.

Re:There might be regulatory issues in the U.S. (2)

Nadaka (224565) | more than 3 years ago | (#36406030)

I am pretty sure its stall speed is going to be 0 laterally, and that is less than 28mph, so he may still qualify. Unless of course that stall speed accounts for vertical motion, in which case his is going to be approximately terminal velocity.

Re:There might be regulatory issues in the U.S. (1)

Johnny Mnemonic (176043) | more than 3 years ago | (#36406098)

They could reduce the size of the fuel tank by 2 gallons, and limit the speed. Smaller fuel tank would reduce weight too, right? Naturally it would also reduce range.

It'd a lot easier to reduce the capabilities to meet regulatory requirement than have to improve something to make it useful.

Re:There might be regulatory issues in the U.S. (1)

idontgno (624372) | more than 3 years ago | (#36406404)

Agreed. It wouldn't be hard to shave off capability until it fits the regulatory guidelines. Of course, since the regulatory guidelines aren't built around the idea of a direct-lift rotorcraft which has to expend engine power just to get off the ground, the Hoverbike's at a distinct disadvantage compared to current-technology ultralights. TBH, as you point out, if you shave off enough capability, you've probably eliminated any practicality.

I just thought I should point out the disingenuous handwaving away of the regulatory challenges in the FAQ's breezy language. "Of course it'll be regulated like an ultralight, if you're unfortunate enough to live in a country blighted by an actual aviation regulation agency."

Does Dr. Venture Know? (1)

F34nor (321515) | more than 3 years ago | (#36405830)

His two ass-clown sons need a place to rest their no-nos.

Yes! Flying cars! (1)

ipwndk (1898300) | more than 3 years ago | (#36405900)

We're way behind on schedule already. They should have happened now.

I really, really hope that this guy and the jetpack guy manages to create a safe and working product. We need flying cars in this world. Why? It was promised so long ago!

It doesn't qualify as an ultralight.. (1)

whizbang77045 (1342005) | more than 3 years ago | (#36405952)

..at least, not under U.S. rules. The bottom speed is slow enough, but the quoted top speed is much too high. Those who point out it probably can't fly as high as quoted are dead on target. Helicopters quote two values: hovering in ground effect (HIGE), and hovering out of ground effect (HOGE). The reason they're quoted is that there is a real problem in getting altitude performance from a rotary wing aircraft. Like all too many new aircraft announcements, the numbers we are quoted appear to be paper calculations, likely by someone not all that well qualified to do the calculations. One of two things is likely to happen: the thing will slide quietly into oblivion, or we'll hear of this spectacular crash. Let's hope it's the former, not the latter.

Holy Crap! (1)

T-Bucket (823202) | more than 3 years ago | (#36405956)

From a pilot's point of view, that looks hideously unstable and unbelievably unsafe... But I'd sure as hell go fly it. It also looks AWESOME...

*yawn* (3, Informative)

Lazy Jones (8403) | more than 3 years ago | (#36406074)

I'd rather take this one [youtube.com] , because it isn't vaporware...

Back to the Future. (0)

Anonymous Coward | more than 3 years ago | (#36406364)

As far as I am concerned I was promised things like this the first time I watched Back to the Future.

I'm torn (1)

antifoidulus (807088) | more than 3 years ago | (#36406400)

I dunno, I want the hoverbike, but I do love The Leader and his Movementarians.

very dangerous you go first (1)

Adam Appel (1991764) | more than 3 years ago | (#36406504)

I see, um, fatal flaws. Mainly the ability to self-right, glide or auto rotate. Basically, anything that might go wrong will result in a uncontrolled flight into terrain.
Load More Comments
Slashdot Account

Need an Account?

Forgot your password?

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>
Create a Slashdot Account

Loading...