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Air Force Lab Test Out "Aircraft Surfing" Technique To Save Fuel
coondoggie writes "It's not a totally new concept, but the Air Force is testing the idea of flying gas-guzzling cargo aircraft inline allowing the trailing aircraft to utilize the cyclonic energy coming off the lead plane — a concept known as vortex surfing — over long distances to save large amounts of fuel. According to an Air force release, a series of recent test flights involving two aircraft at a time, let the trailing aircraft surf the vortex of the lead aircraft, positioning itself in the updraft to get additional lift without burning extra fuel."
Drafting.. nuff said.
Works for cars, bikes, motorcycles, swimmers, why not planes?
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Didn't birds file a patent in this hundreds of thousands of years ago?
What about the lead aircraft? Does he run out of gas first and crash and burn, leaving a new lead to continue the cycle?
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I for one welcome our heavily-armed cyborg goose overlords, and their "V"s of freedom.
So the geese flying in a "V" were on to something all along?
I wonder if you could start using something like this for commercial aircraft. With careful scheduling, you can have aircraft flying in adhoc formations when they are traveling the same corridors.
What could go wrong?
https://www.google.be/search?hl=en&q=geese+flying+in+formation&bpcl=35243188&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&biw=1914&bih=1003&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=tDN3ULuXMMrDtAaV04DgCg
I wonder if they realize that "Apocalypse Now" was not a documentary, and not filmed in real time?
In order to expand our pool of aeronautic expertise, the USAF is offering research positions to those with experience at bicycling long distances. ...Or something like that.
Been there, done that....
Apparently things are a bit more complicated in the air...
Drafting helps by reducing air resistance (drag) and requires you to be really close, this technique is a bit more subtle in that it involves using trailing air vortices to get free "lift". The article had a handy link to explain this... http://www.av8n.com/fly/vortex.htm
Of course I'm sure that someone will draw such an analogy in a pop-science article...
I see folks at the DoD have been watching Mythbusters. As well they should.
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& people think nothing useful comes from turning left for 500 miles...
We're caught in his jetwash! Flame out! We're going in a flat spin! Eject! Eject! Hightway to the danger zone!
Migrating birds have been doing this for years
How would this compare to bird formations?
Wasn't there a Mythbusters that demonstrated that tailgating while an effective way to save gas by drafting, is so dangerous that it isn't worth it.
How is this different? I can't see it being safer to draft/tailgate a plane than a car.
how Goose died in Top Gun?
Why can't large airplanes fly to a very high altitude, then turn off their engines and 'hang glide' down to some lower altitude over a long distance, then turn the engine back on and climb up again?
Geese are going to sue the Air Force for intellectual property infringement.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
It also works for swimming. Swimmers do it, dolphins do it...even educated, bees, oh never mind.
Here you go:
http://www.pezcyclingnews.com/photos/races05/tdf05/mahaney-paceline2.jpg
http://www.ifp.illinois.edu/~smallik/cycling/Paceline.gif
The Airlines should take notice.
Judging by the formations of geese and pelicans I've watched flying by in large groups, I have to assume this effect can be carried from one flyer to the next in a chain and isn't confined to just two flyers. The next question would be "Do all trailing flyers receive this 10% fuel savings, or is there some sort of diminishing return at play?"
If all of the flyers receive the savings, then the airlines might find that sending a small squadron of aircraft, say five DC-10 sized aircraft in formation as opposed to one large "super-liner", is economically beneficial both in terms of lower costs AND lower CO2 emissions. It would also relieve a common problem with current flight scheduling--empty seats. If the "flight" (I'm referring to the squadron idea) did not sell all the seats, they could simply send one less plane--it allows for options in balancing demand vs resource allocation, which would, I assume, allow the airlines to lower costs across the board including ticket prices. It would also allow the airlines to scale specific routes based on demand more accurately--if there is a sudden surge in demand on specific route, they simply increase the squadron size as required.
There is the added benefit of "diluting" the severity in repercussions as a result of mechanical failures/human error--when a super-liner suffers catastrophic failure, everyone dies. In a squadron of planes, a failure on one craft wouldn't mean the death of everyone. Not putting one's eggs in one basket has it's benefits.
Would'nt this have been done by either the British or Germans during the war?
Why don't they just install winglets like the airlines are doing? Winglets reduce fuel usage by minimizing the drag associated with the creation of the vortexes. You get the benefits, even if just one plane is flying.
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Didn't they do this on Mythbusters?
...
They've been talking about doing this for years.
...not jetwash. Jetwash is the turbulent stream of air behind a jet coming from out of the back of the engines. That is mostly dangerous while on the ground, when there is a small, light aircraft sitting behind the jet.
Wake Turbulence comes off the wingtips of *all* airplanes in flight, while the wing is generating lift. It's like horizontal tornadoes spinning off the wingtips. It can flip another airplane upside down Lots of pictures of what it looks like here.
I almost got rolled 90 degrees on short final while landing at EAA Airventure in Oshkosh, WI a few years ago landing behind a P-51 Mustang. I was in a Van's RV-8, which fortunately is very aerobatic and has a quick roll rate. It took full right stick to get the aircraft rightside up again and the whole event was over in a split second, and I landed normally. but with quite the adrenalin dump flowing in my bloodstream, and almost experienced a brown smelly dump flowing in my pants! As soon as I touched down, the tower controller said, "Nice job RV.... Uh, sorry bout that..... (sheepishly) Uh, caution wake turbulence?"
i couldn't be bothered googling, but surely there's a "someone's law" to the effect of "he who uses 'illiterate' in a sentence will invariably misspell it"
I remember an airplane crash near Pittsburgh in the early 1990s, when a plane got too close to another plane and got caught in the wake, causing the plane to plunge.
Once you are out of controlled U.S. Airspace, you are no longer under the jurisdiction of the FAA and this technique could be used by commercial operators to save fuel as well. I wonder how many freightliners you could stack up behind and A380?
You get the most savings at distances that would probably be dangerous due to turbulence. But even further out, you still realize some savings from the formation.
I'm trying to teach myself to set people on fire with my mind... Is it hot in here?
The U.S. Armed Forces can save fuel by not blowing up so much stuff? Things like civilians, weddings, funerals... just an idea.
vorticity is conserved. The flow over a wing is a rotation superimposed on a translation which results in the slower flow underneath and faster on top.The rotation, usually called circulation, embodies a certain value of vorticity which can't disappear. Where it goes is it turns 90 deg at the tip and trails back behind the a/c all the way to the tarmac (vortexes have to terminate at a boundary...the ground).
If the wing is longer, for constant lift, the circulation reduces because a wider swath of air is turned downward so to give the same z-direction momentum flux the amount of "turning" is less.
By flying tip-to-tip, a/c effectively create a longer wing. Physically of course it isn't one wing but happily the highly coherent trailing vortices can be coupled by overlapping them, they rotate in opposite directions so tend to cancel each other out.
(The reason "bees shouldn't be able to fly" is that it appears to take too much energy to create the circulation around their wings every flap. It takes energy to "spin up" the air. How they do it is they slap their wings together at the top, when they separate they shed a vortex back over their wings which gets the circulation going. Not obvious.
Equine Mammals Are Considerably Smaller
Mythbusters did this... worked, but very rough ride.
Didn't birds file a patent in this hundreds of thousands of years ago?
You're not the first and you won't be the last, but birds have been flying for tens of millions of years (or hundreds of millions for various definitions of 'bird'). This is the second time this week I've seen someone talk about an evolved natural phenomenon (like flocking birds) being done for thousands of years. Is it just creationists posting or is it the Führer's fault?
-- Goodwin'd to highlight rhetorical nature of the post.
They most probably did it for millions of years but that doesn't invalidate the thousands of years. Thousands of years is simply a bit incomplete.
Well, I might have a way, but it only works on a semi spherical planet in a vacuum.
..
I think ducks figured that out long ago
On behalf of migrating geese and storks of all species.
Isn't this why foursomes of fighter jets (in the movies, at least), and flocks of migrating geese, fly in a V formation?
Prior art - not patentable.
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