Hard to believe, after 90 years of flying them, that the airplane is all
wrong, specifically the wing, more specifically its fixed position with
respect to the fuselage. After all, why does the whole aircraft have to be
angled up or down just because the wing needs to be pointed that way? Why do
passengers have to be slanted toward the ground--coffee cups and beer cans
rolling down the aisles--merely because the airplane is descending to land?
And why should passengers be slammed with every last blast of turbulence
merely because the wing is bolted stiffly to the fuselage? Why not unbolt
it? If you attached it instead with a hinge, so that the wing could rotate
freely around the spanwise axis, like the slats of a venetian blind, then it
could angle into updrafts and downdrafts automatically, spilling them out,
sliding right through them almost as if they didn't exist.
And think of the safety benefits: a free-castering wing, if properly
built, cannot be stalled. A fixed-wing aircraft stalls because the angle of
attack (the angle between the wing chord and the relative wind) increases
beyond the wing's ability to provide lift. With a freely tiltable wing, the
angle of attack remains constant; the wing always meets the wind at the same
angle. Which means that it will never stall.
So here we have this magical new wing, one that neutralizes turbulence
and resists stalls--automatically, with no input from the pilot. It's enough
to make you wonder why airplanes haven't always been built this way. It's
enough to make you wonder, in fact, whether you couldn't acquire rights to
the concept, then sell it to everyone from Cessna to Boeing. Conceivably,
you could make a fortune.
Which is why, in 1987, Hugh Schmittle, an aircraft salesman, and Odile
Legeay, an international banking executive, founded the Freewing Aircraft
Corporation.
Hugh Schmittle was never one of your junior-pilot types.
"Flying was not a lifelong dream," he says. "I always liked airplanes,
but it was not a case where I ate, slept, and breathed airplanes from the
time I was three. I was a late bloomer."
Forty-five years old, bearded, and slightly paunchy, he still hasn't
gotten his private license, although he's been trying for years. "I
discovered a long time ago," he says, "that if you want not to fly, then
start an airplane company. You don't have time for things like that."
His grand entrance into aviation came only after he quit grad school. He
was on his way toward a Ph.D. in philosophy at the University of Illinois,
where he taught for a while, when he was apprised of a rather alarming
statistic: only three percent of applicants for academic jobs were hired in
any given year. "I decided to bail out and get a real job," he says.
He became an investigator for a federal strike force probing
organized-crime infiltration of the Teamsters union. Shortly
thereafter--because there had to be more to life than this--he took up hang
gliding. "I got all kinds of literature," says Schmittle. "I read up on
everything that was being made at that time, and I ended up buying one of
the first powered hang gliders, a foot-launched thing with a 32-foot wooden
wing. I ordered it as a kit from a guy in California, Craig Catto."
That was in 1976. By the time the kit arrived some six months later,
Schmittle had learned about a wholly new concept for controlled flight. His
friend, Bill Frank, a longtime member of the Experimental Aircraft
Association, had pointed out a long two-part article that had appeared in
Sport Aviation a couple of years earlier. "The Controlwing Aircraft," by
George G. Spratt, described a free-floating wing design that had absolutely
fantastic performance characteristics. Theoretically, it virtually
eliminated turbulence while at the same time was inherently unstallable.
"Floating wings can tilt as required to spill the gusts regardless of
their duration," Spratt wrote. "The advantages of an aircraft that will not
stall or spin are too obvious to dwell upon."
It sounded too good to be true, but Spratt had buttressed his argument
with all manner of facts, figures, diagrams, and pictures, and it made an
impressive case.
Well, thought Schmittle, why not a free-wing ultralight? So he and Bill
Frank set about converting the mail-order hang glider into a free-wing
version. They worked nights and weekends for over two years, and in the end
they came up with a product that had a rather unfortunate drawback for a
prototype flying machine: no matter what they did, it would not leave the
ground. This was depressing.
But Schmittle, with his years of philosophical training, was accustomed
to seeing beyond surface appearances to underlying realities, and to him the
floating-wing theory still appeared correct. He was also enough of an
independent thinker to imagine that he could pick up on his own whatever
practical experience and lore were necessary to design and build a free-wing
craft that actually flew. So he abandoned the kit conversion as an unflyable
kluge, sent away for books and articles about aeronautical engineering and
construction, and became a world expert on the free-floating wing.
A few years later he'd designed and built, from scratch, a wholly new
ultralight, the Freebird Mark I. He took it out to Ridgley-Pelican, a grass
field on Maryland's Eastern shore where he used to skydive, and discovered
that this new craft took to the air quite naturally. So exceptionally stable
and forgiving was it, in fact, that Schmittle used it to teach himself to
fly. "Which is a testament to the stability of the concept," he says, "and
certainly not to any piloting skills I had."
By this time it was 1984, and Schmittle was a regional sales manager for
Aerospatiale, the French conglomerate that manufactures everything from
light aircraft to Airbus airliners. He'd also started his own company in
Maryland--Schmittle Aircraft--to make and market the Freebird. He took the
Mark I down to Sun 'n' Fun, in Lakeland, Florida, a gigantic EAA fly-in, for
his big demonstration, product launch, and introductory marketing salvo.
Where, unfortunately, everybody thought the craft was a "trike," a
Rogallo-wing hang glider that was rapidly becoming passe. "I told them, "No
you don't understand", " says Schmittle, " "this is a revolutionary concept.
It's a free wing but it looks like a trike." But it just became impossible
to get people to see past that to the underlying aerodynamics."
And even when he explained it to them, even after they'd warmed up to the
idea and actually begun to see the point of a free wing, there was always
this residual skepticism, an attitude of "Yeah, well, look, if this is so
good, if it really does all this great stuff, then how come nobody's ever
tried it before? How come every plane in the sky has a pair of fixed wings?"
It was regular as the sunrise, that objection.
"There's got to be some problem with it, you know? I mean, there must be.
Otherwise somebody would have done it by now, right?"
Schmittle lost a lot of money on the Freebird and swore he "would never
start a company again."
The George G. Spratt who wrote the Sport Aviation piece about the
controlwing comes from a long line of George Spratts. In his white clapboard
home in Connecticut, which looks out across Long Island Sound, hangs an oil
painting of one his ancestors, who's also named George Spratt. Spratt's
father and son are both named George Spratt, and not one of these men knows
if he's George Spratt the third, fourth, or ninth; consequently, they
distinguish themselves by initials. This is George G. Spratt, his father was
George A., his father was George R., and so on.
Spratts A. and G., it turns out, were two of the main pioneers of the
free wing, the third being Octave Chanute, the so-called father of aviation.
If there's one thing that all three men would have agreed upon, it's that
the fate of the free wing was essentially sealed back in October of 1902,
when an "oscillating wing" glider was brought to Kitty Hawk, North Carolina,
and delivered to the Wright brothers. The glider, which had wings that
tilted around the lateral axis, had been built at Chanute's behest by one
Charles H. Lamson, who lived in Long Beach, California.
Chanute, a French-born civil engineer then based in Chicago, had been
thinking about flight and building gliders even before the Wright brothers
got interested in the subject, and one of his pet theories was the concept
of automatic stability. If the wings were left free to rotate about one or
another axis, he thought, they would automatically compensate for sudden
gusts. Chanute also believed that the problem of stability should be solved
before powered flight was ever attempted--which is the reverse of the way
things actually turned out.
Between 1896 and 1898 Chanute built a series of movable-wing gliders and
flew them on the shores of Lake Michigan. Later, while vacationing in
Pasadena, Chanute met Lamson, a kite maker who'd recently patented an
oscillating- wing kite. Chanute asked Lamson to build a glider that
incorporated the idea, and this was the craft delivered to the Wrights.
Orville oversaw the flight testing of the oscillating-wing machine on
October 13, 1902. On the beach witnessing the event were both Chanute and
George A. Spratt, father of George G.
George A. Spratt was a retired physician from Coatesville, Pennsylvania,
who'd long had an interest in birds and flying. In 1899 he'd written a
letter to Scientific American, the premier science magazine of the age,
inquiring about the prospects of heavier-than-air flight. The answer (later
framed and installed over George G.'s desk) was: "We cannot advise you to
pursue the subject of aerial flight, there is little promise in it. We do
not know of anyone who would be likely to take an interest in flying
machines." Not overly impressed by this, Spratt built and tested various
airfoils in a homemade wind tunnel, and with these "experiments before the
fan" (as he called them) investigated such arcane phenomena as "travel of
the center of pressure" and other effects, concluding, along with Chanute,
that the stability problem could be solved by the use of a "rocking" wing.
As both Spratt and Chanute watched from the sidelines, the
oscillating-wing glider loomed over the Kitty Hawk sand dunes, first as an
unmanned kite, then with Chanute's test pilot, Augustus M. Herring, aboard.
While Herring's glide was some 50 feet in length, Orville and Wilbur were
making glides of well over 500 feet in their own machine.
Herring was to fly the glider again the next day, but for unknown reasons
he decided not to...and at that pregnant and fateful juncture it passes out
of aviation history. The Wrights dismantled the machine, which Chanute had
given them as a gift, and stored it in their camp building, where it lay for
the next several years, until in the winter of 1908 a storm carried away the
roof of the building and destroyed the glider. By then the Wrights had
conquered the air in a series of fixed-wing craft, and this, in the view of
free-wing enthusiasts, explains why all of today's planes have fixed wings:
nothing succeeds like success.
According to free-wingers, however, that success was decidedly mixed.
With fixed wings and with control surfaces that could raise the nose of the
aircraft to unnatural angles, the Wright Flyers were easily stallable.
Indeed, Wilbur stalled his own glider about three weeks before the test of
the oscillating-wing glider. As he described it: "[The plane] reared up as
though bent on a mad attempt to pierce the heavens. But after a moment
it...slowed up till it came almost to a stop with the front of the machine
still pointing heavenward. By this time I had recovered myself and reversed
the rudder to its full extent, at the same time climbing upward toward the
front so as to bring my weight to bear on the part that was too high. Under
this heroic treatment the machine turned downward and soon began to gather
headway again."
Stability, the Wrights thought, was the business not of the machine but
of the pilot. "The remedy for the difficulty," said Wilbur, "lies in more
skillful operation of the aeroplane." But as George G. Spratt commented many
years later: "This decision has probably cost more lives than any other ever
made in aircraft history."
By the time George A. Spratt died in 1934, he'd built a whole series of
"rocking wing" flying machines. Some flew and some didn't, but it was his
son, George G., born in 1904, who built the first practical versions of
free-wing aircraft. All of them were characterized by automatic stability
and great safety, and they were incredibly easy to fly--"ridiculously easy,"
Spratt says today. He remembers the time he and a friend, Robert Quaintanze,
were testing one of the free-wing flying boats on the Chesapeake Bay.
"Robert knew nothing about aerodynamics," Spratt recalls, "but he knew the
airplane very well mechanically. I was flying around one day and after I
landed he said, "Let me try it." I thought he just wanted to taxi around a
little bit and I said, "Sure, get in and taxi around." He took off and flew
it for about 20 minutes. Came back and landed beside the boat."
Quaintanze, now a retired machinist still living in Coatesville, had been
in the air only once before in his life, as a passenger in a Piper J-3 Cub.
Now, suddenly, "Here I was flying solo."
His biggest problem was locating Spratt's boat again, the Quest III, a
55-foot two-mast schooner, which they were using as their staging point. "I
wasn't used to seeing down," Quaintanze says, "and I couldn't recognize
boats from the air." There'd been fishermen out that day, though, and he
realized that the small specks in the water must be fishing boats, and that
the biggest speck of all must be the Quest III. So he aimed for that point
and landed next to it.
The experience, he says, was proof of the free wing's stability: "The
airplane knew how to fly, that was the main thing. You didn't have to know
how to fly if the airplane did."
Spratt spent much of his life as an aeronautical engineer and designer
for a few aircraft companies; for two of them he constructed some free-wing
prototypes. In 1937 he built one for Bendix, but "the company's board
decided against further development," Spratt says, "on the grounds that as a
major supplier of aircraft components, they should not be building planes in
competition with their customers."
Bendix ended up selling the craft for $50. Then, in the mid-1940s, Spratt
built a roadable version for Consolidated Vultee. It flew perfectly well,
but roadables were never exactly major contenders in the aircraft market,
and that airplane too soon went the way of all flesh.
Later, Spratt concentrated on flying boats, of which he built a number of
free-wing editions with a view to possible manufacture and sale--perhaps as
a kit--but mainly, as it turned out, for his own use and amusement. He flew
them up and down the East Coast and all around Florida, putting in some 700
hours of flying time, all of it self-taught. To this day he's never had an
hour's worth of flying instruction, nor has he acquired a pilot's license.
In Spratt's view, the major aircraft manufacturers aren't going to be
building free wings anytime soon, not that he hasn't tried to persuade them
to. "Their response is "Look, we have patents, we have drawings, we have two
wings and a tail, and you're coming in here asking us to throw all that out
and start all over again like we did a hundred years ago."
"And you go out the door."
In 1983 Hugh Schmittle managed to track down George G. Spratt. He found
him aboard the Quest III, which was tied up at the docks near Charlestown,
Maryland, at the north end of the Chesapeake. The two hit it right off.
"Spratt has a heart of gold," says Schmittle. "He gave me all kinds of
help, plus inspiration."
"He's a likable sort of guy," Spratt says of Schmittle. "He visited me
aboard the Quest III, then I didn't hear another thing from him for a couple
of years...until he decided he wanted to build some planes."
That decision came in the wake of a party thrown by Aerospatiale in
Washington, at which Schmittle met Odile Legeay, senior vice president at
Elite Yachts de France, in Annapolis. Shortly after they met, Schmittle
converted Legeay to the free-wing religion, and she, for her part, convinced
Schmittle that maybe the idea had some business potential.
"Odile ran some numbers on it and put together a kind of "What if?" model
of the business," says Schmittle. "I computerized it so we could play the
"What if?" game a little more easily. But the bottom line was that this
could work out as a company, and that it could work extremely well."
So in 1987 the two founded the Freewing Aircraft Corporation. All they
needed was money, offices, employees, and customers, roughly in that order.
"We decided that I would go back to France," says Legeay. "At that time we
were thinking of light aircraft, and ultralights were a very active business
over there." Schmittle, meanwhile, would try to drum up business in the
States.
In 1988, while working at a bank in Lyons, what should come across
Legeay's desk but a copy of Maryland News, a newsletter published by the
European office of the state of Maryland. Inside was a story headed "A
Maryland Technology Advancement Programme," describing the University of
Maryland's "business incubator" initiative, which furnished startup
high-tech companies with "offices, laboratories, manufacturing facilities,
secretarial and receptionist services, access to computer resources and the
university's library and specialized services, and also business support."
Six months later, Freewing Aircraft had been admitted to the state
program, giving the company a university affiliation and address, plus some
much-needed credibility, not to mention grants that eventually reached
$500,000. Still, Schmittle and Legeay took no salary, and so to make ends
meet each worked nights and weekends, she doing translations, he typing
legal briefs for law firms and playing piano for blues bands.
But the company now had a formal base of operations--some prefabricated
buildings on the edge of the College Park campus, near the university's wind
tunnel--and a couple of employees. Soon they were testing new airfoils and
free-wing models and building a succession of full-scale prototypes. When
these new Freebirds were flight tested, they worked as advertised, dumping
about 75 percent of inflight turbulence and never even thinking about
stalling. Otherwise there was no one element common to them all: as
Schmittle is quick to point out, the free wing is not an aircraft but a
type.
There is, for example, no one way of controlling a free wing. George G.
Spratt's "controlwing" flying boats were controlled by the wings themselves,
hence the name. You banked by turning a steering wheel that tilted the two
wing halves in opposite directions, one up, one down. There was no "pitch
control" to speak of; you added power to climb, reduced it to descend. It
was an aircraft that took off, flew, and landed at the same speed--which was
a function of whatever powerplant happened to be installed.
Schmittle's MK-5, by contrast, has a single straight-through wing and a
three-axis control system based on elevons--hinged panels mounted at the
wing's trailing edge that can be slanted up or down. Left-right movement of
the stick produces differential movement of the elevons, causing the
airplane to bank. Pulling back on the stick deflects both elevons upward;
this causes the wing to rotate to a higher angle of attack, increasing lift.
(The new angle of attack will remain constant for as long as the elevons are
held in the new position. In no case can the elevons raise the wing to a
stalling angle.) Conversely, pushing forward on the stick slants the elevons
downward, lowering the angle of attack. (In a free wing, as in a
conventional airplane, power controls altitude, stick controls airspeed.)
"The plane's going to handle pretty much as a fixed-wing airplane does,"
says Schmittle. "We laid out the cockpit of the MK-5 to be transparent to
the conventional pilot." Indeed, other than the smoother ride and the fact
that you can't stall or loop a free-wing craft, the ordinary fixed-wing
pilot will be aware of few differences as far as the flying goes.
Except, that is, for the matter of flaps. For various technical reasons,
free wings do not take willingly to flaps, which means that approach and
landing speeds are higher, and glide paths shallower, than in an airplane
with conventional flaps. Free-wing buffs, however, have come up with
ingenious ways of compensating for this deficiency. Spratt's controlwing
incorporated a "collective pitch lever," which, when yanked, momentarily
forced the wings up to a higher angle, increasing lift and slowing the
craft, just as if it had flaps.
Freewing's own MK-5, on the other hand, incorporates a device that
temporarily changes the craft back into a conventional airplane: a lockable
wing.
A lockable free wing?
Exactly: at the pilot's option, the Freebird MK-5 can be turned into an
ordinary fixed-wing aircraft for approach and landing.
Naturally, there are reasons for this. Any airplane is a string of
compromises, a bunch of engineering trade-offs flying in close formation.
The free wing is no exception, and so it does not, in the end, give you
something for nothing. You gain stall resistance, true enough, but only at
the price of sacrificing the ability to land fully stalled.
A locked free wing, although strictly speaking a contradiction in terms,
does confer the primary benefits of a normal fixed wing: it allows for use
of flaps, a slow and steep approach, and the customary full-stall landing.
On the other hand, a locked free wing erases one of the main advantages of
free-wing aircraft--stall resistance--in the very flight regime, approach
and landing, where stalls are most likely to occur.
Recently, however, Schmittle invented a way of dispensing with the locked
wing while retaining some of its benefits. His idea was to convert the wing
into an air brake, a veritable barn door, immediately upon touchdown. The
pilot would make a typical free-wing approach--which is to say at a slightly
higher speed, and at a slightly shallower angle, than a fixed-wing craft
would make--and then, at the moment of touchdown, would deflect both elevons
to an extreme downward position, thereby forcing the wing to assume a steep
nose-down angle. Lo and behold, the same airfoil that previously provided
lift is now transformed into a massive wall of drag.
"Not only does this slow the aircraft pretty dramatically," says
Schmittle, "it also plants it solidly on the ground, which increases the
effectiveness of the wheel brakes."
In the spring of 1994, Schmittle applied for a patent on the invention.
So is this miracle wing really all it's cracked up to be?
I don't understand why it hasn't been accepted more than it has been,"
says David B. Thurston, an aeronautical engineer and author of Design for
Flying. "It has advantages in gust alleviation and so forth. I don't see why
it hasn't been more readily accepted for smaller aircraft."
"It appears that it would have some potential for stall prevention," says
Paul Stough, who was project engineer on NASA's General Aviation Stall-Spin
Program, conducted at the Langley Research Center in Hampton, Virginia,
between 1973 and 1989.
Still, both experts voice some doubts about the free wing, especially
regarding its use on aircraft of larger size.
If you have a lot of inertia in the wing, maybe you could get into a
situation in which you could stall the wing," says Stough. "And then what
happens? Does it drop back to a lower angle of attack and everything's
hunky-dory? I don't know."
"You have so much more mass in larger aircraft," says Thurston. "And if
you don't get your balance points just right, then if that mass starts to
move you aren't going to [be able to] stop it the way you can with a control
stick in little airplanes.
"But I really don't know what all the problems are," he adds. "I've never
flown it so I can't tell you."
Indeed, the major problem with the free wing is not so much that it has
limitations--any wing does--but that the very concept, including its pluses
and minuses, is all but unknown in the aviation community.
"I've never heard of it," says Eugene Covert, professor of aeronautics
and astronautics at MIT and former head of the department. "I don't know a
thing about it."
"We have not really considered it," says Dennis Dungan, chief of advanced
design at Cessna Aircraft in Wichita, Kansas. "I've read about the wing and
the pros and cons of it, and I guess the biggest problem in implementing it
in a practical manner would be problems posed by flutter and vibration, both
of which would be excited by turbulence. But to tell you the truth we
haven't worked on it. I only know what I've read."
Schmittle and Legeay aim to change all that. Recently, they've had some
major successes, and when in 1992 the company floated an initial stock
offering, they raked in $1.5 million, including a $600,000 investment from
the Brazilian firm Avibras Aeroespacial. They got some expert help in wing
design when John Roncz, the aerodynamicist who'd done wings for Burt Rutan,
produced a new set of airfoils for Freewing--and wound up purchasing stock
in the company. Finally, Burt Rutan himself got involved, building scale
models, then a full-size version of Freewing's UAV, or unmanned aerial
vehicle, a tilt-body craft whose fuselage can be tilted up or down.
By any standard, the performance of these UAVs is surreal: by the
judicious use of thrust-vectoring, the aircraft can essentially stop dead in
the air and then transition again to level flight. The potential military
and civilian market for these tilt-body UAVs is so large--for border
patrols, power line inspections, and the like--that in 1993 the company
changed its name to Freewing Aerial Robotics. According to Schmittle, the
name change does not signal a backing away from the notion that the free
wing has a realistic application in the passenger market. "Absolutely not,"
he says. "It has always been our plan to develop both manned and unmanned
airplanes and see which hits first. The Gulf war created a window of
opportunity for UAVs--suddenly no commander wants to go to war without them.
Our tilt-body has such spectacular performance, it truly does, that nobody
can match it. There's relatively no product liability with UAVs, so the plan
is to develop them first and later branch out into manned airplanes."
In June 1994, Schmittle and Legeay announced a partnership between
Freewing and the French firm Matra Defense, which will jointly produce a new
ship-based UAV. Whether Freewing can do as well with passenger aircraft is
another question.
George G. Spratt, principal optimist of the free-wing contingent, thinks
they can. "I think there's a good chance of it," he says. "The free wing's
coming. It's the proper way to build an airplane."
The hull of Spratt's flying boat, meanwhile, rests peacefully at the rear
of his house. Facing out toward the water, nose up, its 85-horsepower
Mercury outboard covered tightly with blue plastic, the craft has definitely
seen better days. But at age 90, George G. Spratt still has some vague
hopes--dreams, really--of one day putting the thing back in the water,
firing it up, and once again free-winging it out over the Sound.
Whatever else happens, at least it won't stall.