
Worlds first 'flapless' plane - dchs
http://www.bbc.co.uk/news/uk-england-11431662
======
CWuestefeld
If I'm understanding this right, it's a similar idea to what several F1 racing
teams have been using this year, a concept that's been dubbed the "F-duct".
[1]

The idea is that downforce on the car is generally paid for by aero drag, and
thus if you want grip in the corners, you have to sacrifice straight-line
speed. But what if you could aerodynamically disable that wing on the
straights, so you don't suffer from the drag? (mechanically movable wings are
illegal)

They devised a completely passive system that routes some air from the front
of the car back to the rear, dumping it out behind the engine intake, just in
front of the rear wing. When the driver seals the duct with his knee (or hand,
in the case of Ferrari), the air can flow through this path, thus stalling out
the rear wing, significantly diminishing its aero effect both in terms of
downforce and drag.

From the video, it sounds to me like the plane is doing sort of the opposite:
directing air not to stall, but to cause an aero effect over the normal
surface.

[1] [http://www.suite101.com/content/the-mclaren-f1-f-duct-how-
it...](http://www.suite101.com/content/the-mclaren-f1-f-duct-how-it-
works-a256163)

~~~
hugh3
Thanks for the explanation, I've been hearing about these F-ducts on Formula 1
cars (I follow F1 vaguely) and wondering what the hell all that was about. Is
this the technology that Brawn pioneered last year?

~~~
CWuestefeld
No, this is new this year. It was first seen on the McLaren at the beginning
of the season.

Last year's Brawn innovation was the "double diffuser" -- and I understand
what the diffuser does even less than I understand this.

~~~
hugh3
Ah, I see. Skimming an article on the double diffuser, it seems to just be a
creative interpretation of the rules which allows an extra piece of wing to be
attached by some means that the rulebook-writers didn't think of. It's not
particularly interesting, since it's based more on legalese than on physics.

Personally I find the most frustrating thing about F1 to be the way they keep
inventing new rules in an attempt to make the cars slower. Don't they know
that people watch Formula 1 because they want to see _fast_ cars race?

~~~
goatforce5
A friend of my dad's was really good at finding gaps in the rule books of dirt
track speedway. Like, for instance, it might specify you could only have a
radiator of a certain capacity in the car to cool the engine, but it didn't
specify where it had to be mounted. If you can find somewhere with less mud
being thrown at it or better air flow, then you've got a competitive
advantage.

Eventually some Nascar teams became aware of him. He told them his time was
worth a lot of money. "Money's not a problem!" "If you're serious you'll send
me a blank check."

Two teams sent him checks. He filled in some unnamed amount, waited to see if
it cashed and then ripped up the other one.

He spent a few months in the States, came back, and bought himself one of the
biggest houses in town.

Sometimes chutzpah pays off. :)

------
ErrantX
I'm reading a book all about the Wright brothers at the moment (and this story
made me think about it), absolutely fascinating to see how unbelievably
revolutionary they were.

And in a way this highlights just how much; (one of) their great innovation(s)
was flaps and wing warping for control, it put them light years ahead of other
inventors (who mostly were trying for "automatically stable" flight). It's
fascinating to see that it is only now we are (in a sense) re-innovating their
invention.

If you get chance to read up on the Wrights it is worth it; they were simply
brilliant hackers. They were smart and creative, and had no concerns about
disagreeing with established theory if they thought it was wrong (in fact
going to great lengths to correct theories).

My favourite "story" about them, though, is that the propeller was an after
thought - they spent so long perfecting the wings, flight control and the
engine and had assumed a normal boat propeller would work. When they realised
the error - just a few months before making their attempt they - they hacked
something together using wind tunnel data collected for wing designs. And when
they went to Kill Devil Hills in 1903 were simply confident "it would work",
because they had calculated it to do so.

You may gather I'm a little in awe of them :)

(all of which is not entirely related to this story, but still seemed an
interesting semi-relevant thing to share :))

EDIT: although as pointed out below I am assuming that by "flaps" they mean
all flaps because Ailerons were _not_ a Wright innovation (they used Wing
warping) but a rudder and flaps were part of the Wright flyer and crucial to
the control.

~~~
scott_s
What's the name of the book?

~~~
ErrantX
The Wright Brothers: The Aviation Pioneers Who Changed the World by Ian
Mackersey

<http://www.amazon.com/gp/product/0751533688>

Recommended read (it is a bit effusive in places but also relatively balanced)

------
dpifke
Minor nit: this is not the world's first flapless plane. The Wright Flyer used
a technique called "wing warping," where instead of movable control surfaces,
they flexed the wing to change its shape and lift properties.

NASA has a neat simulator to show how this works here:
<http://wright.nasa.gov/airplane/warp.html>

Also, the article seems to refer all control surfaces - aileron, elevator,
rudder, etc. - as "flaps." I have several hundred hours logged in Citabria
7ECA and 7GCAA aircraft, neither of which have flaps.

"Flaps" in aviation refers to movable panels that increase the wing surface
area and angle of attack in order to produce additional lift at low speeds for
takeoff and landing. Again, NASA has a pretty good explanation:
<http://www.grc.nasa.gov/WWW/K-12/airplane/flap.html>

~~~
InclinedPlane
Was about to post exactly this.

The novelty here is a plane which does not change the shape of the wing in any
way to attain maneuverability.

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CountHackulus
And you thought ice on wings was a problem now, de-icing would be an
absolutely crucial part of this system. If any one hole is even partially
obscured, the balance between both sides is off. Clearly this is computer
controlled and can be compensated for, but it seems to me that there's quite a
few problems to overcome before it comes back to the mainstream.

~~~
spydez
Off the top of my head: that plane had a jet engine, so they could just route
their air lines near the engine for heat, or siphon air from the jet directly.
Then just constantly 'leak' some warm air from all the holes on the wing
surface when in icy conditions.

Or just electrically heat the metal around the holes, like is currently done
for the pitot tube (speed indicator).

~~~
kwantam
Large airplanes usually have electrically heated leading edge surfaces in
addition to pitot tube and stall indicator heat. As you point out, something
like that would work well in this application. There is something of a
drawback, though.

On mid-size planes rated for icing flight, "ice boots" are generally used.
Boots are a rubber surface over the leading edge of the wing that can be
inflated on command. Once ice buildup is sufficient to warrant their use, the
pilot engages the system, which compresses air and then inflates the boots
violently, breaking the ice off the leading edge.

The reason this is more popular for smaller airplanes is because electrically
heated wings take much more power than you can reasonably expect to generate
on something smaller than business jet sized (e.g., Cessna Citation),
especially on approach when engine output is reduced (and when icing can
become the most problematic). Even medium-large twin turboprops like the Beech
KingAir 350 rely on boots.

An alternative technology for smaller airplanes that's pretty unpopular is the
weeping wing, wherein a deicing agent is pumped out through small pores in the
leading edge. It's unpopular because you either have to carry a lot of weight
in deicing solution or risk running out. My father flew a Beech Bonanza A36
that he had retrofitted with the weeping wings, and he's remarked on many
occasions what a pain in the ass they were.

------
hugh3
I assume they mean aileronless rather than just flapless?

Or is "flap" a general term for flaps, ailerons and rudder surfaces?

~~~
jrockway
Flap means something to pilots, but not to popular audiences, I guess. What I
gather from the article is that jets of air replicate the forces that the
ailerons, rudder, and elevators normally provide.

From watching the video, it also seems like it's missing flaps, because of the
shape of the wing. Landing is something they can worry about later ;)

~~~
yock
It could just be that the aircraft doesn't need flaps. The purpose of a flap
is to change the wing geometry such that the aircraft can fly at a lower angle
of attack. This allows the plane to fly slower without stalling the wing. If
the aircraft can already fly sufficiently slow to land then it doesn't need
mechanical flaps to adjust the wing geometry.

As for replacing the control surfaces with jets of air, I can't help but
wonder how that affects airflow around the aircraft. I'd bet something like
this doesn't scale well to larger aircraft.

~~~
jrockway
_I'd bet something like this doesn't scale well to larger aircraft._

I think you're right. I've seen people's model DC-10s that they build, and
apparently at that small scale, they don't even bother with coordinating the
turns. If you want to turn, you just jam the rudder all the way left or right,
and then the plane goes there. In a real DC-10... that probably doesn't work
so well.

(Tried this in X-Plane, and it doesn't really do anything. But the "edge
cases" are poorly handled there; I can't even get a Cessna 172 to spin.)

~~~
yock
I don't know that full rudder deflection is really a corner case! In fact, the
roll orientation of a plane shouldn't affect the effacacy of the rudder so
long as the plane isn't in a slip or spin. The whole purpose of a rudder is to
correct for a difference in lift between the wings in a bank. If there is no
bank, and therefore no difference, the rudder should cause one.

~~~
jrockway
The airflow over the wings when stalling is the "corner case". The usual
models don't apply; if they used a model that could handle any arbitrary
airflow, then the sim would run at 1 frame per hour. So they make some
assumptions for normal flight that are easier to calculate, then they make
some other special assumptions for stalling, and switch between the models as
necessary. I think.

But apparently they don't do anything special for spins or uncoordinated
turns, so you can't try this in X-Plane and be confident that a real plane
would perform well.

Anyone have a DC-10 they don't want?

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sofuture
While not exactly 'flapless', blown flaps have used compressed air as part of
the flap system for quite some time (it's even had time to fall out of favor
due to complexity and costs!)

<http://en.wikipedia.org/wiki/Blown_flaps>

(Though it does look like the article linked refers to ailerons and elevators,
not flaps proper).

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JohnnyBrown
Didn't Orville and Wilbur's prototype steer by twisting the wings?

~~~
marklabedz
Yes, they called it wing-warping apparently -
<http://www.pbs.org/kcet/chasingthesun/planes/wrightfly.html>

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ck2
What do you do when it loses power and you have to land?

(and WTF is with the greenwashing statement that guy made?)

~~~
jrockway
Presumably, the same thing that you do when the motors driving the hydraulic
pumps that drive the control surfaces on a conventional aircraft fail --
control the plane with the other, non-failed control surfaces and with the
engine thrust.

There have been a few cases of big airplanes losing all control surfaces but
still being able to land:

<http://en.wikipedia.org/wiki/United_Airlines_Flight_232>

[http://en.wikipedia.org/wiki/2003_Baghdad_DHL_attempted_shoo...](http://en.wikipedia.org/wiki/2003_Baghdad_DHL_attempted_shootdown_incident)

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Groxx
Figures that this is right on the heels of the news of the first (successful)
human-powered _flapping_ plane.

