NASA Designs All-Electric Personal Flight Vehicle 276
MikeChino writes "NASA is currently working on a personal aircraft that will put jet packs to shame. The Puffin is an all-electric one-man airplane that could be the start of some new and amazing air travel technology. With two prop electric engines, lithium phosphate batteries and a top speed of almost 300 mph, the vertical take off and landing vehicle was originally designed for covert military insertions because it has a lower heat signature than combustion engines. The Puffin would also be super quiet – 10 times quieter than current low-noise helicopters, and since the engine is electric it has no flight ceiling and can fly up to 9,150 meters high, uninhibited by thin air."
"No flight ceiling" (Score:5, Interesting)
Re:"No flight ceiling" (Score:5, Interesting)
I'm not an engineer so I can't comment on the operating ceiling of the the thing but speaking as a former private pilot, 9,150 meters (FL 28, roughly) is already well above the point where the pilot-in-command would be allowed to operate without supplemental oxygen.In fact, up that high you'd be messing with the three-holer transport jets and would probably need a pretty high-quality heated flight suit.
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Well Everest is just under 9km up, and people have scaled it without oxygen. However these were mountaineers, and not duty free guzzling pilots.
I also am completely unqualified in aerodynamics, but I would assume (most probably incorrectly) that the ceiling would be limited by the speed the rotors turn and also the length/surface area they have (assuming the pilot is appropriately dressed for the occasion).
I'm quite interested actually in any responses that could shed some light on this... seems pretty coo
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Well Everest is just under 9km up, and people have scaled it without oxygen.
[citation needed]
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Well Everest is just under 9km up, and people have scaled it without oxygen.
That may very well be true but, at least in the US, the pilot-in-command of an unpressurized aircraft is required by FAA regulations to use supplemental oxygen when flying at 10,000 or feet for more than a certain amount of time.
Re:"No flight ceiling" (Score:5, Informative)
Also that's a totally different scenario. High altitudes like that without oxygen while mountain climbing are achievable only by letting the body acclimatize for several weeks at progressively higher altitudes during the climb.
You take anyone at sea level and put them immediately at 9km up without oxygen, they will pass out within minutes.
Re:"No flight ceiling" (Score:5, Interesting)
Ask the fucking craziest of them all, http://en.wikipedia.org/wiki/Joseph_Kittinger [wikipedia.org] .
Personal experience is as good as it gets...
"Capt. Joe W. Kittinger achieved the highest and longest (14 min) parachute jump in history on August 16, 1960 as part of a United States Air Force program testing high-altitude escape systems. Wearing a pressure suit, Capt. Kittinger ascended for an hour and a half in an open gondola attached to a balloon to an altitude of 102,800 feet (31,330 m), where he then jumped. The fall lasted 4 minutes and 36 seconds, during which Capt. Kittinger reached speeds of 1142 km/h (714 mph) [9]. The air in the upper atmosphere is less dense and thus leads to lower air-resistance and a much higher terminal velocity."
Gives the phrase "No Fear" a whole new meaning.
Capt. 'Cannonballs' Kittinger (Score:4, Interesting)
Wow! And I thought I was nuts for loving HALO[High Altitude, Low Opening] jumps!
[With full equipment/kit load+body wt. @ around 275 lb./125 Kg] I was told that the max. velocity was around 130 mph/209 kph...compared to 714 mph, I guess I was a piker!
Offtopic side note:The highest we ever jumped from was around 17,000 feet altitude; I found my minimum altitude for releasing my chute was approximately 385 feet, but it hurt!
(we were advised that the minimum altitude was 500 feet...I had to test this)
[using the US Army version of the Ram Air-square type 'chute [wikipedia.org]]
That was also where I got over my fear of heights, once I was thrown out of a perfectly good airplane!
Re:Capt. 'Cannonballs' Kittinger (Score:4, Funny)
I found my minimum altitude for releasing my chute was approximately 385 feet, but it hurt! (we were advised that the minimum altitude was 500 feet...I had to test this)
So are you still chasing that Darwin Award, or have you given up ;-)
Re:"No flight ceiling" (Score:5, Informative)
The other factor is that the typical propeller does become less efficient as the air gets thinner, so there is still a ceiling. Jets (turbofans) have less of an issue with this. From a quick Google, It appears that above Flight Level 240 (24000) the majority of the thrust of a turbofan comes from the jet exhaust, while at sea level most of it comes from the fan.
For me, the sheer fear factor of looking down from 9000 meters (30,000 feet) in not much more than my flight suit would be more than I'd be ready for.
But I think this could be the inspiration for the long-awaited personal aerial commuter vehicle - especially if operation can be automated, and if the redundancy mentioned in TFA can achieve no-single-point-of-failure. If routing were handled by a central traffic control system, and local traffic position were handled by an agent swarm, it could work pretty well. The VTOL capabiliy means you could land in a parking space, or on the roof. And the 80 mile cruising range would be sufficient for commuting.
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As a skydiver with HALO experience I can tell you that there is nothing to fear. You do not really have depth (or is that height) perception at that altitude. Yes, everything does look tiny and as a skydiver I sometimes wonder if I will make the target (a football field looks like a tiny dot or button below). However, since this is powered flight, that's no
Re:"No flight ceiling" (Score:4, Informative)
From a quick Google, It appears that above Flight Level 240 (24000) the majority of the thrust of a turbofan comes from the jet exhaust, while at sea level most of it comes from the fan.
While possibly true in practice, it has nothing to do with altitude. Thrust comes from the mass flow rate, times the change in velocity. Aside from fighter jets on afterburner, the exhaust coming out of a jet engine will be subsonic. The speed of sound is proportional to the square root of temperature, so the hot core flow will be much faster than the relatively cool bypass flow.
So what relevance is this to anything? By 'sea level' the quote you saw probably meant 'take off', or zero forward velocity. FL240 would be cruise at 500-550 knots. You have high mass flow but low velocity through the bypass fan, and high velocity but low mass flow through the core. At cruise speed, the velocity differential of the bypass flow may only be 1/4 what it was static, while the much hotter and faster core flow still has more than half its differential. Modern high bypass turbofans have ratios of 9:1 or better, so the bypass will still be producing more thrust than the core even at the reduced efficiency.
Re:"No flight ceiling" (Score:4, Funny)
Yeah. To correct the GP:
Justin.
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Hmm. Interesting point. Also, to some extent I think it is a matter of choice. I never had issues with height when I was a kid - climbed 200 ft. fir trees like a monkey, used to hang out in the top and read books. More recently I've had issues. But then I bought a sailboat. It took me a while to get myself to start climbing the mast but once I got up there (65+feet above ground at the time) and started appreciating the view, the fear went away. I still respect the height but I don't seem to have the
Thank you, Google! (Score:5, Funny)
PSA: don't blindly search Google if you want to find out what a "three-holer" is - I don't think any of the top hits are what he's referring to.
Re:"No flight ceiling" (Score:4, Informative)
Your about 10,000 feet off.
Class "A" Airspace begins at FL180 (18,000 ft AMSL) and continues up to FL600 (60,000ft AMSL). AMSL = "Above Mean Sea Level"
To fly in class "A" airspace you must be following a filed IFR Flight Plan and have two way radio communication. These are the only requirements.
There is one instance where one is required to fly VFR in class "A" airspace. Look it up! I will give you a hint: FAR part 91 and AIM 6-x-x
yes I am a pilot.
Re:"No flight ceiling" (Score:5, Funny)
That was my personal favorite quote.
It has no flight ceiling... so it could go up to about 9,150 meters
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From TFA:
so it could go up to about 9,150 meters before its energy runs low enough to drive it to descend
i.e. not a flight ceiling, a limitation of energy capacity.
Earth to Orbit vehicle? (Score:2)
This is odd that someone hasn't already cashed in on this. Is this a possible precursor to a simple earth to orbit vehicle? From what I read in TFA, the limit quoted is simply due to the capacity of the batteries, however this uses a simple rotary blade system similar to a helicopter for lift. It would definitely fail when the atmosphere thinned out.
Can someone familiar with this type of design give an idea of exactly how high this could be expected to fly if the batteries were not the limiting factor?
Re:Earth to Orbit vehicle? (Score:4, Informative)
Not in any way, shape, or form. Getting to 20-30000 feet, if it was capable of that, with a very small payload, it essentially worthless in terms of orbital. To get into orbit the chief challenge is velocity. To get that (without other far more interesting technical breakthroughs) you need a HUGE rocket with very large amounts of fuel. So there is really no role at all for this teeny little helicoper/VTOL airplane.
Brett
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I'm not implying they could get into orbit with this vehicle as it obviously will require atmosphere for the rotor blades to be effective, but in a general sense. Specifically getting a launch vehicle as far into the atmosphere as possible before switching to a different means of propulsion like a typical rocket.
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But you can't possibly lift a big enough rocket with this little airplane. It barely works for tiny payloads when you drop the booster from an L1011. What this would amount to is far less effective than a rockoon, where a HUGE balloon lifted small rockets to ~100,000 feet. None of them came close to gaining sufficient velocity. Trying to raise the launcher 10-20000 feet ( at essentially zero velocity) is not worth the effort, no matter how big the lifting device is. This little thing is going to have proble
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From TFA: "the Puffin can lift a person with just 60 horsepower."
Again, I'm not saying this specific vehicle is what would be used. I asked if it could be a precursor to future designs. What is to prevent someone from putting higher HP electric motors? The scale on this one is tiny. Imagine putting a little muscle into this.
Re:Earth to Orbit vehicle? (Score:5, Informative)
I'm not implying they could get into orbit with this vehicle as it obviously will require atmosphere for the rotor blades to be effective, but in a general sense. Specifically getting a launch vehicle as far into the atmosphere as possible before switching to a different means of propulsion like a typical rocket.
Achieving orbit is about speed ('delta v'), NOT altitude. It takes much more energy to get the horizontal speed to the required level than to reach the required altitude. Getting above the atmosphere helps, but not all that much.
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"The orbital velocity of a satellite depends on its altitude above Earth. The nearer Earth, the faster the required orbital velocity."
Is this accurate?
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Yes. What you need is for the force pulling you towards the earth to be equal to the force necessary to pull the satellite into a circular orbit rather than inertial straight line motion: G*m_earth*m_sat/r^2=m_sat*v_sat^2/r. So v_sat is inversely proportional to sqrt(r). Any faster and you'd be spiralling outwards; any slower and you'll spiral inwards.
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That's exactly what a 3 stage rocket is designed to do. There are no free rides in physics.
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VTOL aircraft have to be overpowered to pull off the takeoff and landing, but with a top speed of 250 km/h (ground speed, presumably) and those little wings I wouldn't count on getting to 9000 metres, never mind higher.
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Not only does it become difficult to generate lift, but to keep the electric motors cooled. You're always going to have losses in the form of heat and that's generally carried away by the air moving past the motor. An overheated motor when that's what's keeping you from plummeting isn't cool... literally.
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At those altitudes, wouldn't the fact that the air be EXTREMELY cold? (I think -52c or so at 30k feet?)
Re:"No flight ceiling" (Score:4, Informative)
At those altitudes, wouldn't the fact that the air be EXTREMELY cold? (I think -52c or so at 30k feet?)
The problem is that air is far less dense at those altitudes. There's roughly a third the air at sea level. For example, suppose you're trying to keep the engine below 80C. An air flow at sea level and 20C that barely does it, would be equivalent to a third the airflow at -100C.
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Most of a ~200 mile commercial flight is spent ascending and descending. Not so much time spent at cruising altitude. Props are significantly more efficient at low altitudes, compared to turbofans. Recall that we are talking about turbine engines in both cases! The 'burn fuel in air' part of the engine is *exactly* the same. The efficiency com
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As for ultimate limits, the difference between stalling and breaking the sound barrier was about 50 knots for the U2 flights. That may have been plus or minus 50', but I think it was actually +/-25. Memory fails. Anyway, 68K feet is a *seriously* nerve-wracking place to fly if your airplane can't do Mach.
It was +/- 5 knots. Luckily at that altitude, there are no gusts.
CG concept only (Score:5, Insightful)
By March, the researchers plan on finishing a one third-size, hover-capable Puffin demonstrator, and in the three months following that they will begin investigating how well it transitions from cruise to hover flight. They are already looking past the Puffin, however.
And that's why we'll never see a full sized vehicle.
The next-generation of this design might incorporate more than just two pairs of prop rotors, so that if one was struck by, say, a bird or gunfire, the aircraft could survive on redundant systems. "We could make it so there's no single point of failure--that's the cool next step," Moore says.
Ya know what a cool next step would be? Actually making the vehicle.
Still only 20 minutes (Score:2)
n principle, the Puffin can cruise at 240 kilometers per hour and dash at more than 480 kph.
With current state-of-the-art batteries, it has a range of just 80 kilometers if cruising,
That's a flight time of (80km/(480km/hr)) = 20 minutes. Less than impressive even if they actually were to produce it.
Although that is a problem they seem to have solved by making it with batteries which don't exist yet.
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Your V-22 video was an unfortunate example. The V-22/XV-15/BA-609 tilt rotor platform is generally stable and easily controlled, ala this video [youtube.com].
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4 crashes since its inception? That really isn't so bad. You should compare with other military planes. Also at least half of those crashes were due to maintenance, parts failure issues and really have nothing to do with the actual design of the craft. I would say the press did a pretty good job of convincing everyone that the V-22 was a flying deathtrap.....
Comment removed (Score:4, Insightful)
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To be fair, it has a body count [wikipedia.org] of 30 people in 3 separate incidents, even before it reached operational status. Very few defense programs must own up to that kind of numbers.
That said, I now see them flying around most days of the week and they are sure cool!
thin air? (Score:2)
since the engine is electric it has no flight ceiling and can fly up to 9,150 meters high, uninhibited by thin air
Seriously, who who wrote this? Thin air = less air for the props to bite, and less air to provide lift for the wings.
And who calls an electric motor an "engine"? Gaaaah. If this were Wired, I'd be more forgiving on both counts- but this is Scientific American!
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Seriously, who who wrote this? Thin air = less air for the props to bite, and less air to provide lift for the wings.
While you're right about this, of course, the problem is compounded with combustion engines because with altitude the thinner air means less oxygen to burn fuel with. Just when you need more power to turn the prop faster (or at higher pitch)*, you have less power because of relative oxygen starvation. Electrics avoid that problem, but yes ultimately you reach an altitude where you can't get
I understand all this (Score:2)
While you're right about this, of course, the problem is compounded with combustion engines because with altitude the thinner air means less oxygen to burn fuel with
No kidding; I don't deny this. But the article doesn't say that it has a higher ceiling; it says: "It has no flight ceiling."
That is utter bullshit!
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I don't think this was a scientific error or reporting error but rather an English error.
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I thought NASA had solved our orbital launch problems for ever.
Re:thin air? (Score:5, Interesting)
Note well that the highest flying prop plane ever, the Aerovironment Helios [wikipedia.org], flew to 96,000 ft -- far higher than almost any other plane (probably the only one that could sustain that altitude was the SR-71). The Helios was powered completely by solar cells and electric motors.
psst, NASA, just one little thing. (Score:5, Funny)
My question is.. (Score:2)
How long will this stay in the air?
Jet packs last about 90 seconds? Hmmm
Re:My question is.. (Score:5, Informative)
Well, let's see...
FTFA:
[...] the Puffin can cruise at 240 kilometers per hour [...] With current state-of-the-art batteries, it has a range of just 80 kilometers if cruising [...]
So it can stay up about 20 minutes.
It would work for me. I could get to work in about 15 minutes and plug it in. At the end of the day, it's all charged up and I take it home.
So, yes. I want one.
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"Puffin Man" doesn't have quite the same ring to it though, compared to the names of other super hero's...
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Seeing as how they are now making R/C planes with electric motors (the jet models come to mind) I think this could have some sort of reasonable range. Even a couple of hundred miles would be plenty. Remember that airplanes can be more efficient than cars because there is actually much less resistance.
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Becoming airborne is not a requisite of a body with a lower coefficient of drag.
Design a car with a body of an airplane and you will get great fuel efficiency, the only problem is convincing people to drive it.
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Go the "Green Spin" (Score:2)
Moore and his colleagues ... named their craft the Puffin because "if you've ever seen a puffin on the ground, it looks very awkward, with wings too small to fly, and that's exactly what our vehicle looks like," he explains. "But it's also apparently called the most environmentally friendly bird, because it hides its poop, and we're environmentally friendly because we have essentially no emissions.
Yeah, environmentally friendly except for that nasty lithium stuff in the lithium phosphate batteries.
I can't help but wonder what the glide slope on this thing is like - with those small wings, how quickly will it hit the ground if it runs out of power.
Comment removed (Score:4, Interesting)
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Oh great, so not only would you break both of your legs but you would have a wicked case of motion sickness to boot.
*spinspinspin* *thud* *crack* *BLEEEEEEEEEEGH* *whimper*
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Could always install one of those light aircraft parachutes they've got now a days. Trick would be finding a place to set it down in an urban setting.
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> ...that nasty lithium stuff...
There is nothing particularly nasty about lithium.
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when i can buy one at walmart (Score:2)
Cool toy, but we can't have it. (Score:2, Insightful)
Been there, done that (Score:2, Insightful)
Is Elmer Gantry Available? (Score:3, Insightful)
I will believe it when I see it. Batteries that good are a dream. And as far as the nearly 30,000 foot ceiling of this device cold and thin air might be a serious issue. Pilots generally like to breath and being turned into a frozen, air starved corpse is not a goal for most of us. Or are we supposed to think this thing with have a closed cabin with oxygen and heat available? Jesus, we can't even get good batteries for electric bicycles yet.
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Exceptions for lawyers, politicians, and SCO employees.
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Three words: Heated pressure suits.
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And part of the project is named Icarus? (Score:5, Insightful)
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Let's try to see if we can get them to test out a project named after a flightless bird.
There is an ISP in Australia called 'Dodo', and their most commonly used marketing statement is 'Internet that flies'. I thought that was kind of clever given that the Dodo is flightless, and extinct.
Uncle (Score:2)
Seriously, it would be a hell of a lot of fun, and probably a challenge to learn to fly as competently as a good driver drives a car.
But the day they open a dealership in Toronto is the day I stop driving. Not that pedestrians are all that safe in this city these days, but I'm already concerned enough with a significant portion of the other people on the road. No way I'm going to share airspace with them too!
Computer-Controlled (Re:Uncle) (Score:2)
I suspect it wouldn't be sufficiently safe unless it was computer-controlled. It's not that I fully trust computers, just more than I trust everyday humans controlling flying machines.
Unlike most cars, proper proximity broadcasts and other requirements would allow the computer to have
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Why have a pilot? I doubt the thing will stay airborne without a computer anyway. I can't believe that a pilot would be as capable as an autopilot computer in this instance.
Innumeracy? (Score:3, Interesting)
From TFA:
electric aircraft are much quieter than regular planes—at some 150 meters, it is as loud as 50 decibels, or roughly the volume of a conversation, making it roughly 10 times quieter than current low-noise helicopters.
I admit that I never have gotten a handle on math beyond algebra but am I wrong by being bothered by statements like 10 times quieter? Wouldn't be better to say "makes only one-tenth the noise?" Or am I being pedantic?
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just imagine "X times quieter" means x^(-1) the volume
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If I make a noise of N volume, you make a noise of N-M volume, and bob makes a noise of N-3M volume, bob is 3 times quieter than you. Quiet is relative. Quieter is a measure of the difference between differences.
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No, not as far as I am concerned. You are not being overly pedantic, even by local standards. It's a very awkward choice of words.
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You're not being bad. The "x times less" construct is really clumsy. IMO, it's mainly journalists and marketers using it; they're just punching (small new number) / (big old number) into a calculator, rounding it, and then the brain shuts off and they just say the new one is (result) times less.
The slashdot summary blurb is even worse, since sound is measured in decibels, which aren't linear. (IIRC, 3 db is a factor of two... so 33 db would be twice as loud as 30 db, and half as loud as 36 db). So if a norm
Battery powered aircraft:Completely unrealistic (Score:4, Interesting)
Li-ion-anything has an energy density equaling 1% of gasoline. Lithium phosphate batteries are worse than others in energy density, but safer.
So for the same fuel weight, instead of a 2 hour flight reserve, you would have 72 seconds.
Until there is a radically different battery, this is unrealistic.
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http://www.yuneec.com/
http://www.electraflyer.com/
http://www.pipistrel.si/planes/35
Yes, the energy density of the best batteries are about 5% that of gasoline (not 1%) but a gasoline engine is only about 20% efficient at converting chemical energy to mechanical. An electric motor is more like 90%. It's no where
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According to TFA, the electric engine is ~95% efficient, vs ~20% for a gasoline engine. So we're up to nearly 6 minutes now :)
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Unless I'm mistaken, AV gas is pretty much regular gas with an octane rating of between 105 and 109. It's not nitro-methane or anything special.
When I was young and stupid I used to mix it about 50/50 with pump gas in my GSXR-750 and pretend to be a street racer. It didn't make much difference if any - for reasons that are obvious to me now, but back then I wanted to believe.
Poor design of tail (Score:2)
If it had a frikkin' laser... (Score:2)
...I'd buy THAT for a dollar!
Actually, if this thing ever becomes an actual product, I'll buy one.
I can always get the laser in the aftermarket.
A Tail Sitter? (Score:2)
Tail sitters like the Convair Pogo [fiddlersgreen.net] were a beast to land.
The transition from horizontal to vertical flight has always come with substantial penalties - weight, complexity, power, control and cost.
There's some truth still to old adage that what "looks right, flies right." To my eyes this thing looks all wrong.
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I don't think this will be flown stick and rudder. More like point to a map location on your iPhone and press the "Go There" button.
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The Puffin would have the pilot in a standing position during takeoff and landing.
I'm still not convinced this gives him the visibility and control he needs.
The tail sitters spend most of their time in tethered flight inside a hanger. This ultralight tail sitter looks like it could be batted about by a heavy breeze.
Hard ceiling (Score:2)
Have installed aircooled equipment in aircrafts. Already at 5000m, air density is 50% of sealevel. Your cooling fan will have to suck in 200% of the air. At the same time, the rotors have to work harder to hold you up in the thin air. That requires more cooling as well. Maybe 300% at 5000m. At 10000m, maybe 1,000% increase.
You will quickly reach a hard ceiling. And with 60 seconds of battery life it is pretty theoretical anyway.
Japan got it first (Score:2)
Cobra was first! (Score:2)
Bah! Hardly original. Cobra C.L.A.W. anyone?
http://www.yojoe.com/vehicles/84/claw/ [yojoe.com]
Do I understand this correctly? (Score:2)
It's late and I'm tired, but what they're saying is, if you be Puffin, you be flying high?
I'm down with that.
I see... (Score:5, Funny)
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At 9150m, a plane such as this which is 180kg + say 80kg human (260kg) holds about 23.34 Mega Joules [wolframalpha.com] of gravitational potential energy. Can 45kg batteries hold this much energy to push it up that high? (Not even considering the power required)