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Air Force Lab Test Out "Aircraft Surfing" Technique To Save Fuel

samzenpus posted about 2 years ago | from the watch-your-spacing dept.

The Military 205

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."

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drafting... (1, Offtopic)

arkane1234 (457605) | about 2 years ago | (#41623435)

Drafting.. nuff said.
Works for cars, bikes, motorcycles, swimmers, why not planes?

Apparently different than drafting... (4, Informative)

slew (2918) | about 2 years ago | (#41623603)

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 [av8n.com]

Of course I'm sure that someone will draw such an analogy in a pop-science article...

Re:Apparently different than drafting... (5, Insightful)

Penguinisto (415985) | about 2 years ago | (#41623843)

OTOH, nature already provides a perfect example: Geese have been doing it for literal ages [wikipedia.org] and likely for the same reason (though instead of burning excess liquid fuel, it keeps them from being tired).

Re:Apparently different than drafting... (3, Funny)

sycodon (149926) | about 2 years ago | (#41624159)

The Waterfowl Association will file suit for Patent violation and Trade Secret violations.

Re:Apparently different than drafting... (4, Funny)

jd2112 (1535857) | about 2 years ago | (#41624343)

It will be tied into the aircrafts autopilot system, thus being done "with a computer" thus invalidating any prior art and qualifying for patent protection for that reason as well.

NASCAR (0)

Anonymous Coward | about 2 years ago | (#41623629)

& people think nothing useful comes from turning left for 500 miles...

Re:NASCAR (5, Informative)

h4rr4r (612664) | about 2 years ago | (#41623759)

Drafting is also used in racing leagues that turn right and have drivers and fans educated enough to read.

Re:NASCAR (0)

Anonymous Coward | about 2 years ago | (#41624449)

Drafting is also used in racing leagues that turn right and have drivers and fans educated enough to read.

NASCAR has road courses as well. I think you mean racing in cars that don't cover their wheels vs cars that cover their wheels. That's how the distinction is made in racing at any rate. And within open wheel vs closed wheel there are many, many more levels. A true racing fan would be educated enough to understand that.

Re:NASCAR (5, Funny)

Type44Q (1233630) | about 2 years ago | (#41624547)

racing leagues that turn right and have drivers and fans educated enough to read.

Q) What has two hundred legs and twelve teeth?

A) The front row at a Willie Nelson concert.

Re:drafting... (1)

Jeng (926980) | about 2 years ago | (#41623649)

Works for cars, bikes, motorcycles, swimmers, why not planes?

Turbulence due to the plane and it's engines. At least that is what I would assume to be a problem with drafting in the air.

It's not like this works for boats.

Re:drafting... (1)

DrData99 (916924) | about 2 years ago | (#41623721)

It does work for boats. You can surf the stern wake.

  But you need to get fairly close, and control your speed carefully. Not worth the effort.

Swimming (2, Funny)

Anonymous Coward | about 2 years ago | (#41623873)

It also works for swimming. Swimmers do it, dolphins do it...even educated, bees, oh never mind.

Re:drafting... (2)

The Grim Reefer (1162755) | about 2 years ago | (#41624217)

Works for cars, bikes, motorcycles, swimmers, why not planes?

Turbulence due to the plane and it's engines. At least that is what I would assume to be a problem with drafting in the air.

I've talked to some pilots and they call it jet wash. The larger the plane the more severe it is. When I fly I occasionally listen to the air traffic control chatter. Larger planes like 747, 757, 767, 777, etc are always referred to as "heavy" after their call sign. It's to help ATC remember to keep the spacing a little further behind these planes due to more jet wash. At least that's what I've been told. I assume it's true as it makes sense.

Re:drafting... (1)

Luckyo (1726890) | about 2 years ago | (#41624353)

This is correct. Jet wash is basically the vortex effect in the air after the plane passes that is caused by drag. It causes extreme turbulence and is dangerous enough for large aircraft to have mandated spacing on take off or land from the same runway. For example, one of the issues with A380 has been that it's so big, that they had to increase the biggest "slot" allocated for take off and landing due to jet wash caused by it.

Re:drafting... (4, Informative)

AK Marc (707885) | about 2 years ago | (#41623683)

It's not drafting, it's flying in a V like birds. The lead bird works harder than the rest, and the lead changes when the front gets tired. Birds have "known" about this phenomenon for thousands of years (at least). But I'm surprised someone didn't patent it and charge the military for doing it.

Re:drafting... (1, Informative)

nairnr (314138) | about 2 years ago | (#41623953)

It is drafting in a sense... The vortices off of the wings create a slight updraft which reduces the effort that the trailing birds need to expend. I think Mythbusters took this one on. There is an effect but the trailing plane has a very narrow margin that they have to stay within to see any benefit.

Re:drafting... (1)

Mercano (826132) | about 2 years ago | (#41624531)

They were doing this with pretty lightweight acrobatic planes. Perhaps the big cargo planes put off enough of a wake that the following planes don't have to be quite as close? Still going to be a bumpy ride though.

Re:drafting... (0)

Anonymous Coward | about 2 years ago | (#41623993)

The lead bird works harder than the rest, and the lead changes when the front gets tired.

In bicycle racing that's called drafting.

Re:drafting... (2)

Dan East (318230) | about 2 years ago | (#41624153)

It always blows my mind seeing geese flying in such perfect V formations as they migrate in the spring and fall. I can't help but wonder if this is some sort of instinct that is pre-programmed into their brains, or if they can actually feel the difference and thus simply do whatever is easiest, or if there is some other aspect (maybe visual or even social?) that prompts the behavior and it just so happens that it is also more efficient.

Re:drafting... (5, Funny)

Anonymous Coward | about 2 years ago | (#41624223)

I think it is learned behaviour of not flying in the poop-stream of the bird directly in front of you.

Re:drafting... (0)

Anonymous Coward | about 2 years ago | (#41624303)

So, this leads to a serious question that was raised in philosophy. My Google-Fu is failing me, but there was a serious argument that birds in a swarm are communicating extremely complex information to each other to maintain a bird swarm, possibly even on a psychic level, or at least some means we weren't then able to measure. By way of computer modeling, we were able to find that swarms a echelon patterns are more related to applications of birds taking the path of least resistance, keeping an even distance from eachother and to just head in the same general direction as your neighbors. here's a little bit of it [wikipedia.org]

Re:drafting... (0)

Anonymous Coward | about 2 years ago | (#41624189)

How do you force a military to pay for something you patented when it comes to a tactical maneuver. As far as I can tell the patent holder would not have a way to stop them at all except in the courts and then the country who owns the military would have to allow it and why the hell would they do that. Besides the Canadian Geese claim prior art.

Re:drafting... (4, Informative)

Thelasko (1196535) | about 2 years ago | (#41624211)

But I'm surprised someone didn't patent it and charge the military for doing it.

The innovation isn't in the concept of "drafting" another plane. The innovation is in the autopilot system that does it safely and automatically. As shown on Mythbusters the concept is viable, but a human is not capable of keeping the plane in the "sweet spot" safely for an extended period of time.

Re:drafting... (1)

Kaenneth (82978) | about 2 years ago | (#41624361)

I believe the federal government exempts itself from patent law anyway.

Re:drafting... (1)

viperidaenz (2515578) | about 2 years ago | (#41624247)

Drafting is utilising the low pressure zone behind another moving object. What the air force are doing is utilising vertices that provide extra lift. Same thing birds have been doing for millions of years.

If an aircraft were drafting, they would been to spend more fuel because the lower pressure provides less lift. Since they can't counter than by going faster (smashing in to the plane they are following) they would need to increase their own lift, which produces more drag.

prior art (0)

Anonymous Coward | about 2 years ago | (#41623453)

Didn't birds file a patent in this hundreds of thousands of years ago?

Re:prior art (4, Funny)

daremonai (859175) | about 2 years ago | (#41623527)

Their application was rejected. The patent examiner said, "sorry, this just looks like a bunch of chicken scratches!"

(They were actually sparrow scratches, but never mind that.)

Re:prior art (4, Funny)

HeckRuler (1369601) | about 2 years ago | (#41623733)

Obviously they didn't have their ducks in a row.

Re:prior art (1)

sconeu (64226) | about 2 years ago | (#41623829)

Clearly, you have an eagle eye, to have spotted that.

Re:prior art (1)

AuMatar (183847) | about 2 years ago | (#41624123)

These jokes are real turkeys

Re:prior art (2)

jd2112 (1535857) | about 2 years ago | (#41624383)

This thread needs to go the way of the Dodo.

Re:prior art (-1)

Anonymous Coward | about 2 years ago | (#41624433)

This thread needs to go the way of the Dodo.

No way you chicken! I'm finding it very uplifting!

Re:prior art (0)

NatasRevol (731260) | about 2 years ago | (#41624473)

I'm going to put my head in the sand.

I wouldn't crow about that-- (1, Redundant)

Xandrax (2451618) | about 2 years ago | (#41624527)

...

Re:I wouldn't crow about that-- (1)

es330td (964170) | about 2 years ago | (#41624575)

Next thing you know he'll be strutting like a rooster.

Re:prior art (1)

ZeroSumHappiness (1710320) | about 2 years ago | (#41623605)

Depends on how the first to file/first to invent law gets interpreted once it goes into effect. Birds never filed AFAIK. (They found it "obvious.")

Re:prior art (-1, Flamebait)

Desler (1608317) | about 2 years ago | (#41623687)

Except first-to-file/first-to-invent have to do with deciding who to award a patent to if multiple people seek to patent the same idea. It changes nothing with respect to prior art. First-to-file still uses prior art to determine patentability of the claims. Are you people who repeat this really this dimb?

Re:prior art (2)

ZeroSumHappiness (1710320) | about 2 years ago | (#41623913)

Sorry, I was just making a joke. Didn't mean to step in your pet shit pile.

Re:prior art (0)

Anonymous Coward | about 2 years ago | (#41624359)

If two people come up with the same thing at the same time independently, its sounds that the patent should be rejected since it was apparently obvious to multiple people in the field.

Who's up first? (1)

Ostracus (1354233) | about 2 years ago | (#41623457)

What about the lead aircraft? Does he run out of gas first and crash and burn, leaving a new lead to continue the cycle?

Re:Who's up first? (3, Insightful)

Anonymous Coward | about 2 years ago | (#41623491)

Just because the lead craft doesn't get to save gas, doesn't mean there is not a net gas savings for the entire system.

Re:Who's up first? (3, Funny)

Freddybear (1805256) | about 2 years ago | (#41623513)

Change positions every so often. It's more fun that way. ;)

Re:Who's up first? (3, Funny)

Morpf (2683099) | about 2 years ago | (#41623523)

You can switch lead on-the-fly.

Re:Who's up first? (3, Interesting)

NEDHead (1651195) | about 2 years ago | (#41623525)

Actually, in most examples of drafting, the benefit extends to the leader as well, reducing the tail drag associated with a solo player. As I recall, the benefit generally increases as you add cars to the train as the lead drag and tail drag are spread over more units.

Re:Who's up first? (1)

Baloroth (2370816) | about 2 years ago | (#41623665)

Given the distance involved (200 feet or so) I doubt that effect will be present in aircraft "vortex surfing". I think the physics involved are quite a bit different from drafting in a car, but that is really just a guess.

Re:Who's up first? (2)

nairnr (314138) | about 2 years ago | (#41623997)

The vortices of planes last a long time. At airports when you are dealing with the big planes they have to leave minutes later so that the vortices have time to dissipate. Otherwise there is severe turbulence for the next plane. Watch a plane coming down through fog and see how long it takes for it to settle down...

Re:Who's up first? (4, Insightful)

AK Marc (707885) | about 2 years ago | (#41623749)

Firstly, this isn't drafting. Secondly, the lead would likely swap periodically, as birds have done for thousands of years. Drafting airplanes won't work for the same reason helicopters hovering can crash wile under full power (google "settling with power" for an areodynamic description of what would happen when multiple wings travel through the same air). Yes, I am a pilot.

Re:Who's up first? (1, Informative)

NEDHead (1651195) | about 2 years ago | (#41623897)

Of course it is drafting. It relies on mitigating the detrimental vortex effects associated with moving object terminations in a fluid environment by spreading the wasted energy over a longer object. Same as the efficiencies of longer boats in water, and longer props, whether on planes or windmills. No different in concept.

Re:Who's up first? (4, Informative)

AK Marc (707885) | about 2 years ago | (#41624559)

Drafting, defined as "following someone/something in a manner to reduce your aerodynamic drag by traveling in air moving at a lower relative velocity" excludes this act.

If you feel it is drafting, please state the definition of drafting you are using, as I've not seen a definition of drafting that would include this.

It does not depend on mitigating detrimental vorticies. NASCAR drafting does, and the lead car gets the benefit from the reduced drag. This does not benefit the vehicle in the front and is the following car using a predicted vortex to its advantage, while traveling through otherwise undisturbed air. Thus "drafting" where the folower uses the lead car to "break the air" is not happening.

Rather than having to define "drafting" to a bunch of morons who are too stupid/lazzy to google, I'd rather discuss the efffect of this on commercial aircraft for the rest of us, flight lanes with airplane flocks saving fuel. Or discussions on how much the winglets affect this effect. But no, it's all a discussion of the definition of "drafting" with a bunch of google-illiterite people.

Re:Who's up first? (1)

wonkey_monkey (2592601) | about 2 years ago | (#41623967)

Secondly, the lead would likely swap periodically, as birds have done for thousands of years.

But isn't that because birds get tired? Planes don't get tired - the lead plane will just burn more fuel than the rest, but as long as it's got enough for the trip, why does it need to swap out?

Re:Who's up first? (2)

Xenx (2211586) | about 2 years ago | (#41624249)

The reason to rotate lead would be to conserve fuel for all planes, so you can travel further on the same size tank.

Re:Who's up first? (0)

Anonymous Coward | about 2 years ago | (#41624579)

The reason to rotate lead would be to conserve fuel for all planes, so you can travel further on the same size tank.

You're assuming the consumption to fuel savings ratio is linear. In other words, for every X amount of fuel consumed by the lead plane, you would save Y amount of fuel where X and Y are single order variables. If the ratio was non-linear, however, it might not make as much sense to swap out the lead plane. Especially if the rate of savings is increasing in time over the rate of consumption. That would make swapping out the lead plane pointless and would probably eliminate much savings.

I wonder though, would the lead plane feel drag from it's "drafting" companions? From what I understand in automotive drafting the lead car has to work a little bit harder, not just because of air resistance but because having the car behind it increases it's drag making it a little bit more difficult to accelerate.

Re:Who's up first? (2)

Chris Burke (6130) | about 2 years ago | (#41624371)

But isn't that because birds get tired? Planes don't get tired - the lead plane will just burn more fuel than the rest, but as long as it's got enough for the trip, why does it need to swap out?

Migratory birds like geese have insane flight muscles, composed almost entirely of red muscle, and they are not really susceptible to muscle fatigue. The main limitation for them is fuel.

So the reason planes would want to swap leaders is more or less the same reasons as the birds do: To increase the range of all members of the formation.

Re:Who's up first? (1)

gman003 (1693318) | about 2 years ago | (#41623537)

You could have them change off every so often, so none are in the lead for the full time. But that's really only if you're doing this to extend your range. If your concern is mainly decreasing costs, you would just fly them like this, but within the range of a solo aircraft. You would probably even fuel up each craft with enough fuel to handle it solo, just in case something happens.

Re:Who's up first? (0)

Anonymous Coward | about 2 years ago | (#41623539)

Say it would take 6 units of gas per plane for them to fly separately. Drafting/Surfing, the second plane could do it in 4 units.

Now, instead of 12 units to fly both plans, it only takes 10.

Re:Who's up first? (0)

Anonymous Coward | about 2 years ago | (#41623615)

Or, they switch positions mid-trip and it only takes 5 units per plane.

Re:Who's up first? (0)

Anonymous Coward | about 2 years ago | (#41623885)

But then we still have a total of 10...

Re:Who's up first? (0)

Anonymous Coward | about 2 years ago | (#41624185)

True, but say the maximum capacity for the plane is 5. You can now fly for 6 units worth of distance with only 5 units of capacity. And, 10 is still better than 12.

Re:Who's up first? (1)

MightyYar (622222) | about 2 years ago | (#41623705)

Put more fuel or less cargo in the lead aircraft.

Re:Who's up first? (1)

zill (1690130) | about 2 years ago | (#41624011)

Apparently birds could figure this one out on their own, yet you can't.

Geese (0)

Anonymous Coward | about 2 years ago | (#41623477)

I for one welcome our heavily-armed cyborg goose overlords, and their "V"s of freedom.

Clever... (0)

Anonymous Coward | about 2 years ago | (#41623505)

So the geese flying in a "V" were on to something all along?

Re:Clever... (2)

Chris Burke (6130) | about 2 years ago | (#41623701)

Well yeah, and it's been known for a long time they do this to save energy for those behind the leader, and that they trade off leaders from time to time.

Sometimes it takes a while for something in one discipline to reach another (I'm guessing ornithologists and military aerospace engineers probably don't rub elbows too often, but what do I know), and it's not always obvious that an idea in one area would apply to another (geese and airplanes are in fact different).

Still, I can't help but scratch my head that they're just now testing the idea.

Commercial Aircraft Possibilities? (1)

Koreantoast (527520) | about 2 years ago | (#41623511)

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.

Re:Commercial Aircraft Possibilities? (2)

Jeng (926980) | about 2 years ago | (#41623837)

Companies operating commercial aircraft have different regulations about how they fly vs the military.

If this were ever used commercially, I don't think it would be allowed with passenger aircraft, just cargo. The risk is just too damn high for so little reward.

Re:Commercial Aircraft Possibilities? (2)

viperidaenz (2515578) | about 2 years ago | (#41624489)

The risk is just too damn high for so little reward

That depends on the cost of fuel vs lawsuit

Re:Commercial Aircraft Possibilities? (3, Informative)

nairnr (314138) | about 2 years ago | (#41624051)

No, there are strict rules for vertical and horizontal separation for planes depending on VFR/IFR http://en.wikipedia.org/wiki/Separation_(air_traffic_control) [wikipedia.org] Not likely this will be changed anytime soon for safety reasons...

Big, clumsy, fast and close (3, Interesting)

Shavano (2541114) | about 2 years ago | (#41623515)

What could go wrong?

Re:Big, clumsy, fast and close (4, Funny)

Spectre (1685) | about 2 years ago | (#41623639)

I think you are attending the wrong dance clubs ...

Re:Big, clumsy, fast and close (1)

couchslug (175151) | about 2 years ago | (#41624255)

Very close formation flying has been standard training and practice since aerial refuelling was adopted.

Maintain your altitude and distance or you force disconnect, or even get a boom through your canopy and die.

http://en.wikipedia.org/wiki/Aerial_refueling [wikipedia.org]

Re:Big, clumsy, fast and close (2, Informative)

Anonymous Coward | about 2 years ago | (#41624267)

When I read about the F/A-18 probing the airspace behind a DC-8 I thought the F/A-18 pilot had to have big brass ones.

Back in the 70's there was a story in the San Diego Union about a private airplane that got flipped on its back as it was approaching Lindbergh Field in San Diego. The flip happened too close to the ground and the occupants were killed. The flight controllers had allowed the private plane to come in too soon after a large commercial jet had landed. The accident led to a doubling of separation times in those situations, e.g., small plane landing after a large one.

gee, groundbreaking discovery (0)

Anonymous Coward | about 2 years ago | (#41623549)

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

hm (1)

HPHatecraft (2748003) | about 2 years ago | (#41623553)

I wonder if they realize that "Apocalypse Now" was not a documentary, and not filmed in real time?

Now Hiring: Cyclists (1)

DaneM (810927) | about 2 years ago | (#41623573)

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.

Mythbusters (1)

Anonymous Coward | about 2 years ago | (#41623589)

Been there, done that....

Mythbusters (5, Interesting)

Zordak (123132) | about 2 years ago | (#41623609)

I see folks at the DoD have been watching Mythbusters. As well they should.

Re:Mythbusters (0)

Anonymous Coward | about 2 years ago | (#41623987)

sadly enough it wouldn't surprise me if this was true.

General watching the discovery channel with his grand kid.

General"Blimey...." runs off grabbing his jacket and cap.

I'm in I'll engage! (4, Funny)

superstick58 (809423) | about 2 years ago | (#41623643)

We're caught in his jetwash! Flame out! We're going in a flat spin! Eject! Eject! Hightway to the danger zone!

Re:I'm in I'll engage! (0)

Anonymous Coward | about 2 years ago | (#41623995)

It's "I went through," not "Highway to" the danger zone. Posting anonymously because I'm ashamed I know that.

Re:I'm in I'll engage! (0)

Anonymous Coward | about 2 years ago | (#41624273)

You're _exactly_ wrong.

http://www.kissthisguy.com/9541misheard.htm

Also posting as anon.

Re:I'm in I'll engage! (0)

Anonymous Coward | about 2 years ago | (#41624469)

Goose died for our sins.

Like ducks (1)

Anonymous Coward | about 2 years ago | (#41623691)

Migrating birds have been doing this for years

birds (0)

Anonymous Coward | about 2 years ago | (#41623747)

How would this compare to bird formations?

Mytbusters episode (0)

Anonymous Coward | about 2 years ago | (#41623783)

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.

Re:Mytbusters episode (1)

PPH (736903) | about 2 years ago | (#41624047)

Automation. Drafting isn't safe if you depend on your own reaction times and vigilance. But with automation, it should be safe for both cars and airplanes.

Besides, airplanes tend not to slam on their brakes like cars and trucks do.

Wait! Isn't this (1)

I Read Good (2348294) | about 2 years ago | (#41623795)

how Goose died in Top Gun?

Fuel Saving (0)

Anonymous Coward | about 2 years ago | (#41623809)

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?

Re:Fuel Saving (0)

Anonymous Coward | about 2 years ago | (#41623943)

Would you turn off your car's engine to coast down an off-ramp?

Re:Fuel Saving (2)

ZeroSumHappiness (1710320) | about 2 years ago | (#41623969)

Because it costs a shit-ton of energy to get up to that high altitude. Much more than just going directly from point A to point B.

Re:Fuel Saving (3, Informative)

gstrickler (920733) | about 2 years ago | (#41624213)

Half right. It does take a lot of energy to climb, but you regain most of that on descent making it approx 0 net change. However, flying at high altitude reduces air density, and therefore, drag, resulting in a net fuel savings.

It's a bit more complicated still, propeller driven planes may lose some propeller efficiency in the thinner air. For any given plane, there is a limit on how high it can fly, and trade-offs in drag vs propulsion efficiency, lift vs weight, as well as design (pressure and operational temperature) limits. However, as a rule, the higher you can fly the plane (within it's design limits), the more fuel efficient the trip will be. Short flights may be constrained a bit because the optimal climb rate and optimal descent rates might limit the max height to less than what the optimal height the plane is capable of.

Re:Fuel Saving (1)

ZeroSumHappiness (1710320) | about 2 years ago | (#41624491)

Interesting, I didn't realize that the reduction in air density at height greatly offsets the cost to get there. I assumed it would be similar to how gunning it to 130 MPH in a car and then costing down to 55 will kill your fuel economy.

Re:Fuel Saving (1)

willy_me (212994) | about 2 years ago | (#41624285)

Because it would take longer so the airline would not be able to charge as much for tickets. Also, the crew would have to be paid for more hours for each flight. Maintenance would also cost more per flight as each flight would involve logging more air time. And I would feel bad for the air traffic controllers - their job would get significantly more difficult.

Risking a patent lawsuit (0)

HangingChad (677530) | about 2 years ago | (#41623833)

Geese are going to sue the Air Force for intellectual property infringement.

Re:Risking a patent lawsuit (1)

wonkey_monkey (2592601) | about 2 years ago | (#41623981)

It's first-to-file, not first-to-fly.

It's a paceline (0)

Anonymous Coward | about 2 years ago | (#41623979)

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. (3, Interesting)

Anachragnome (1008495) | about 2 years ago | (#41624201)

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.

ww ii (0)

Anonymous Coward | about 2 years ago | (#41624289)

Would'nt this have been done by either the British or Germans during the war?

Wait a Minute (3, Interesting)

mk1004 (2488060) | about 2 years ago | (#41624291)

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.

Re:Wait a Minute (1)

Anonymous Coward | about 2 years ago | (#41624471)

Winglets reduce the induced losses associated with vortex generation, but can't come close to eliminating them--in fact, there exists an absolute lower bound on how much vorticity for a finite-span wing can be reduced. For the best fuel savings, you'd do both!

There is a danger, though. The maximum upwash occurs just outside the core of the trailed vortex... unfortunately, the maximum downwash occurs just inside the trailed vortex. Pilots, especially of smaller aircraft, will want to fly in a tight V formation to maximize efficiency but will need to be cautious to stay outside of the danger zone where a strong downwash could be induced on the inboard wing and a strong upwash on the outboard wing causing a rapid roll over to occur. This is way the FAA has established minimum following distances for aircraft on approach--a significant limiting factor to current runway capacity.

Didn't they do thi son Mythbusters? (0)

Anonymous Coward | about 2 years ago | (#41624295)

Didn't they do this on Mythbusters?

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