by Seth Shulman
"I'm going to pour gasoline on
that motor and set it on fire once we get our new four-stroke engine
Elwood Norris, inventor, promoter, and full-throttle enthusiast about the
dream of building a personal flying machine, is joking about the
temperamental Italian two-stroke engine that powers a contraption he
refers to as his baby. Right now his baby won't fly. Experimental
aviation, circa 2002, is grounded by a faulty carburetor. The machine,
officially known as the AirScooter, sits on the edge of a roughly mown hay
field near Newport News, Virginia, somewhat ungainly on its big red rubber
pontoons. Norris' aircraft is an open-cockpit, twin-rotor ultralight
helicopter that, today, is scheduled to make one of its first
demonstration flights, orchestrated for this magazine. The glitch is
embarrassing, but Norris is not really fazed. The AirScooter will fly, he
promises. And, indeed, before the demo is over it will display its
potential—it's the closest thing yet to a sturdy, mass-marketable flying
machine for casual amateur use.
How can there be, a hundred years after Kitty Hawk, any talk about a dream
of personal flight? Didn't Otto Lilienthal, the Wright brothers, Glenn
Curtiss, Charles Lindbergh, Amelia Earhart, William Lear, and all the
other aviation pioneers put that dream to rest? The answer is that the
AirScooter and its ilk, a class of flying machines that dates back many
decades, represent a kind of suburban sequel to the Wright stuff, in which
the science of aviation is brought home, domesticated, made, as Chrysler
described its minivan, "garageable." The idea gained momentum in the
optimistic era after World War II, and remains appealing because it
promises, as the car once promised, personal power and adventure for the
ordinary man or woman. With the car now often gridlocked on roads to and
from suburbia, a machine that can fly above the car suggests freedom from
the tyranny of two-dimensional blacktop. It is—the grand vision—a fantasy,
but enormously attractive.
The airplane never really promised this. The development of the
helicopter, though, seemed to. As Edwin Teale speculated in this magazine
almost 70 years ago, four years before the first single-rotor Sikorsky
helicopter flew, "Office buildings could be capped with honeycomb cells
holding the helicopters of the workers, each craft dropping into its
compartment in the morning and rising straight up from it at night; aerial
shuttle lines could link centers of population with airports and suburbs.
These are not fantastic visions. . . . As these words are being written, a
cable from England tells of dramatic progress."
To really deliver on the dream, then, the personal flying machine cannot
be dependent on an airstrip or lake—as even the smallest ultralight plane
is—but must take off and land vertically. It must be as easy to operate as
an SUV, which no conventional helicopter is. And it must be cheap enough
for the middle class car owner—the standard American dreamer—to buy and
maintain, far cheaper than a Cessna or little Bell chopper.
Homebuilt helicopters and gyrocopters
(machines with unpowered overhead rotors) already exist, of course, constituting
a finicky subset of machines flown by mechanically inclined enthusiasts; the
Popular Rotorcraft Association has chapters in 30 states and five other
countries. But such devices remain either too difficult to fly or too
time-consuming to maintain to be suitable for mass-production and wide
This is where Norris enters. After developing a string of inventions—including a
linear-tracking phonograph, a forerunner of the sonogram, and one of the first
prototypes for cellphone earpieces—Norris, a small-plane pilot, turned to the
personal flying machine because, he says, "Everybody I have met seems to have
this dream to get off the ground and defy gravity." Norris claims his Henderson,
Nevada-based AirScooter Corp. will have its first production machines on the
market by early 2003, at a likely price of $25,000 to $50,000—somewhere between
the cost of a well-equipped Ford Explorer and a Lincoln Navigator. And, he
promises, you can learn to fly it in an hour.
What will you get for the money? No leather seats or plush interior, that's for
sure. Norris' prototype AirScooter has a fabric mesh sling seat, the kind you
might find on a lawn chair, and handlebars that look like they've been lifted
from a mountain bike because they have been lifted from a mountain bike. It has
a vertically mounted engine topped by two sets of spindly coaxial helicopter
blades—one above the other on two concentric driveshafts—that rotate in opposite
directions. And then there are the pontoons, which are specially manufactured by
a company that makes whitewater rafts.
If the AirScooter seems stripped down to bare essentials, there's a reason. Its
creators wanted it to weigh less than 254 pounds so it could duck most Federal
Aviation Administration regulations by qualifying as an ultralight craft. Most
important to Norris and his team, this designation means that you won't need a
pilot's license to fly the AirScooter (although other ultralight rules do put
limits on speed, altitude, and the like). The machine was built with attention
to every ounce: Few of its parts exceed a pound and a half. There is hardly any
instrumentation. The rotor blades are a mere 14 feet long. At a remarkable 247
pounds, the AirScooter is lighter than many motorcycles—not including its two
30-pound pontoons, which get by courtesy of an FAA safety rule. Think, then, not
of a flying Ford Explorer but of an airborne ATV.
To go left or right, you turn the handlebars to the side; to move forward or
back, you push the handlebar assembly out or pull it toward you. These
instinctive motions adjust the position of the yaw paddles or the rotors (see
diagram, page 52). To go up or down, you twist the handlebar throttle with your
right hand—just as you would to accelerate on a motorcycle. The throttle simply
increases the rpm of the blades above your head to lift the craft higher in the
air. That's it. Pitch, yaw, and roll, all neatly taken care of. No foot pedals
or fancy dials. None of the five separate hand and foot controls you'd find in
the cockpit of a conventional helicopter.
Critical to the AirScooter's potential,
however, is the part not yet demonstrated: the new engine. The main problem with
most personal aircraft to date is that to minimize weight they employ two-stroke
engines, which are noisy, temperamental, highly polluting, and have a perilous
tendency to seize up. The 65-horsepower four-stroke Norris is having built
weighs only 80 pounds, but it is, he says, quiet, reliable, low-maintenance,
cleaner, and most of all, safer. It's made of aluminum and magnesium alloy and
protected from melting at high temperatures by an inner ceramic coating. In
addition, it's continuously lubricated by a pressurized distribution tube from a
separate oil tank, so it should run smoothly not only when the AirScooter is
horizontal but also during twists, turns, and other maneuvers. Norris knows that
the four-stroke is the key to delivering on the AirScooter's promise. Though it
added greatly to the cost (he's sunk several million dollars into the AirScooter
project so far), he founded a second company, AeroTwin Motor Corp., solely to
develop the four-stroke. (As this issue went to press, testing remained
imminent. Norris promised a tour de force.)
Even without the new engine, the machine simply feels good to sit in. And here
in Newport News, I've been promised a chance to fly it, tethered for safety. I
love aviation but I'm no pilot, so the notion of learning to operate a
vertical-takeoff flying machine in less time than it takes to figure out how to
set up a new PC is terrifically appealing. All of which means, of course, that
I'm a target customer for the AirScooter. For now, though, I just sit. The crew
can't get the peevish two-stroke to cooperate.
"Personal flight has always been my dream," says veteran inventor Craig vet- ter.
"The time has arrived." Vetter, of Carmel, California, is best known for
pioneering motorcycle designs like the celebrated Triumph Hurricane, but for the
past few years he's been threatening to launch a contest to build a viable
personal flying machine. Vetter hasn't found sponsors willing to put up the
$100,000 prize money he thinks he needs to draw major talent, but the idea is
not empty posturing: In the 1980s, Vetter sponsored a fuel economy contest that
showcased an array of prototype vehicles that could achieve almost 500 miles per
gallon in real highway conditions. The proposed rules for the new contest set
out Vetter's version of the dream: to build a vehicle that can fly "low and slow
. . . so it won't hurt too much if we crashed. . . . This is a contest to reward
mastery of airspace from the surface to 10 feet up." In what we might call
personal airspace, flying machines would cruise over or around obstacles and
stick to roads only in bad weather. In sun, they would scoot over the open
A handful of inventors could be
contenders if Vetter jumpstarts his contest, most of them taking advantage
of recent advances in lightweight composite materials and computer-aided
design. Along with Norris, former Navy combat pilot Michael Moshier leads
the pack. Mosh-ier's brashly conceived SoloTrek XFV (short for
Exo-Skeletor Flying Vehicle) has made dozens of short, tethered flights at
the Sunnyvale, California-based headquarters of his company Millennium
Jet. (This magazine described the SoloTrek last October.) If the
AirScooter is like an ultralight airborne ATV, Mosh-ier's machine—which is
supposed to have a range of 150 miles and a top speed of 80 mph—resembles
a strap-on, flying, high-performance superbike.
Moshier says his preoccupation with personal flight began when he saw the
U.S. Army-funded rocket pack that was featured in the 1965 James Bond film
Thunderball. The device, a backpack powered by rocket fuel, was real and
powerful, but terribly impractical—it ran out of fuel in about 20 seconds.
Today's SoloTrek has a 120-horsepower engine; two ducted, turbine-like
fans are positioned on either side of the pilot and spin in opposite
directions. A joystick in each of the pilot's hands communicates with a
computerized stability system: One controls speed, the other steers.
Because it's compact and has no exposed blades, the SoloTrek could allow
users to land in cramped spaces. But since the housed rotors sit side by
side, rather than on top of one another, the machine is potentially less
stable than the AirScooter: If the flaps on the SoloTrek's two fans get
out of sync, the machine could become unbalanced.
At 500 pounds, the SoloTrek doesn't meet the FAA's ultralight designation,
so you'd need a pilot's license to fly it. If you could afford to buy it,
that is: The complex avionics could push its price tag well past $100,000.
For now, Moshier envisions soldiers, not civilians, strapping on his rig.
Despite millions in Pentagon funding, money has been a chronic problem,
but Moshier says he devotes "150 percent of his time" to his invention.
Moshier's devotion pales beside that of maverick inventor Paul Moller.
Moller's M400 Skycar (which this magazine covered in March 2000) features
four horizontally mounted ducted fans, each powered by two Wankel-style
rotary engines, that together produce 720 horsepower. Moller intends his
Skycar to take off like a helicopter, fly much the way a car is driven,
and navigate on autopilot using the satellite-based Global Positioning
System: Clearly, he's reaching for the full realization of the personal
flying machine. He intends to deliver a working version of the sort of
craft depicted in films like The Fifth Element, in which urban flyers that
resemble old, round-edge Chevy Caprices zip about on invisible aerial
roadways. Problem is, though Moller claims his Skycar made a few-seconds
hop last year, no one outside his Davis, California-based company has yet
to witness the feat. The project has sapped his energies and at least $200
million of his and his investors' fortunes for some 40 years. He hasn't
lost faith. "We've had our dark days," he says. "But I know in my heart
that this technology is coming."
The helicopter may have been
the genesis of the idea of personal flight, but it also dashed hopes when,
after being perfected in 1943 by Igor Sikorsky, it proved far harder than
an airplane to fly. The dominant design employed by the big names in
commercial helicopters—Sikorsky, Bell, and Hughes—employ the so-called
single main torque system. The natural tendency in a single-overhead-rotor
craft is for the body to spin in the opposite direction as the rotor. The
small rear rotor was added to counteract that effect and keep the
helicopter steady. But the inherent instability of this system means that
even accomplished pilots find conventional helicopters hard to fly:
Control requires constant corrections, deft hand-foot coordination, and
intense concentration. Further, helicopters are complicated contraptions,
with blades that must change pitch as the pilot steers (as AirScooter test
pilot Jack Nolan puts it, "The blades fly the helicopter"). And
complicated contraptions are, of course, expensive.
The solution is a dual rotor system—with two equal rotors spinning in
opposite directions—to counteract the gyroscopic torque and yield a net
torque of zero. That eliminates the need for a tail rotor; as a result,
the controls can be vastly simplified. The rotors themselves can be
simplified, too, because their pitch can be fixed. With that
design—adopted by Norris and others—the pilot can simply increase the rpm
of the blades to go higher, or shift the weight of the aircraft to change
the rotors' attitude and to steer.
Consider the wee Gen H-4, brainchild of little-known Japanese inventor Gen
Yanagisawa, which weighs a mere 155 pounds, employs four 10-horsepower
125cc engines, and sells for around $29,900 as a build-it-yourself kit. It
reportedly can cruise at up to 55 mph for 30 minutes on a 21/2-gallon tank
of gas. Why wouldn't this machine trump Norris' AirScooter concept? Well,
the AirScooter looks positively rugged compared with the Gen H-4. Picture
hanging from two spinning rotors attached to what looks like a small
generator, in something that resembles an office chair with long spindly
legs. From a distance, an operator looks like he's literally flying by the
seat of his pants.
Not good enough, says Norris. "The AirScooter is going to be the first to
put all the pieces together in a workable flying machine that anyone can
buy off the shelf, and that is nearly maintenance-free and easy for anyone
to operate," he claims. "Heck," he says, "even people in wheelchairs will
be able to fly it."
Another offshoot of the dual counter-rotating
blade concept is a class of machine called a flying platform. This design
originated in the mid-1940s with engineer Charles Zimmerman's notion that the
instability of overhead rotors could be overcome if the operator stood above the
blades, controlling the machine with body movement; he called this his "flying
shoes" concept. Aviation pioneer Stanley Hiller made a version of the flying
platform that flew in 1955. Today's Hummingbird, made by the Israeli firm
Aero-Design & Development, is a typical current example. A little over 7 feet in
diameter, the machine resembles a giant tuna can; it contains two sets of
counter-rotating propeller blades and is powered by four tiny 22-horsepower
engines. The operator stands in a waist-high cage affair on top. The Hummingbird
can reportedly fly for about 30 minutes. AD&D says it hopes soon to sell the
machine as a kit for about $30,000. At 320 pounds, it's above the FAA's
ultralight limits, but build-it-yourself kits are exempted from these rules. The
Performance Aviation Manufacturing Group in Williamsburg, Virginia, meanwhile,
is already taking orders for a $50,500 kit for a similar flying platform design
called an Individual Lifting Vehicle. Company officials say it could be used by
ranchers to track cattle (a personal ranching machine, an aero-horse) or by
immigration officials to patrol borders.
And so it goes. There's no end to the iterations of this idea. Rafi Yoeli, an
Israeli engineer, ex-Boeing, has a 1,200-pound prototype in his Tel Aviv living
room of a machine called the CityHawk. A two-seater powered by twin gas engines
and a pair of 6-foot-wide internal fans (one in front of the other, on a machine
that looks a bit like a giant sandal), it relies on a computer-controlled system
of 300 flaps to translate the pilot's commands—or will, if CityHawk ever flies.
Now stop for a second: Imagine personal airspace, filling up with CityHawks,
AirScooters, SoloTreks, and Skycars. How likely is that? Not very likely
anywhere near the suburbs. Paul Takemoto, an FAA spokesperson, notes that the
fine print of Part 103, the regulations governing ultralight craft, requires
pilots to fly low enough that they can always see the ground, and much more
significantly, forbids flying through congested areas, in controlled airspace,
or even over open areas where lots of people might be congregating. Furthermore,
if commercial sales of personal flying machines were ever to really take off,
the FAA would no doubt leap to provide additional oversight. "We certainly
wouldn't hesitate to take another look at these regulations if we ever felt the
need to do so," Takemoto says, no doubt with considerable understatement.
Even Craig Vetter, who
envisions legions of "low and slow" craft breaking the blacktop gridlock,
acknowledges two critical safety issues. First, there's the problem of
whirling propellers like "swinging knife blades." Designers must build
these craft "so a child could come up and touch them anywhere before
takeoff and not get hurt," Vetter says. Second, there's what Vetter calls
the problem of the "dead man zone." Altitudes of 12 to 350 feet, where
many of these machines would operate, are high enough to kill a pilot in a
fall, too low for a conventional parachute to work. New escape gear will
be needed, Vetter says.
The first successfully marketed personal flying machine is unlikely to be
a flying car, zooming over Expeditions as they make their slow way into
the city. It's more likely to be an airborne ATV, scooting over empty
rural fields: a fun, reliable toy, no more expensive than a decent boat,
bringing the thrill of aviation to the man or woman who's tried the latest
jet-ski and wants to get some real air.
At the Virginia hay field, Art Phelps, one of AirScooter's lead engineers,
has retrofitted the stuttering two-stroke engine with a jury-rigged new
dual carburetor system. Meanwhile, AirScooter test pilot Nolan, a former
race car driver decked out in a black jumpsuit, conducts spot checks. He
examines the so-called teeter stops that keep the rotors from wobbling
until they are steadied by angular momentum when in motion. He tests the
rotors' belt drive. He finds a loose wire to the tacho-meter and works
with Phelps and a handy pocketknife to crimp it back into place.
Finally ready, Nolan hops into the sling seat, twists his right wrist on
the motorcycle-like throttle and, once the engine has finally coughed to
life, makes a graceful vertical takeoff. He loops around the open field
like a hummingbird—stopping in midair, hovering, rotating the craft at
will—then comfortably does a few laps at about 10 feet above the ground
before gracefully alighting on a little cement tarmac. The potential and
the allure of the AirScooter are unmistakable in this masterful
low-altitude flight. The thing flies—albeit noisily, another problem with
helicopters—and it looks incredibly easy to use. Nolan's test run is
followed by a round of ceremonial cannon fire from a small Civil War
replica a team member has brought to the site, as well as some hollering
and a hearty round of high-fives.
Nolan makes a number of short demo flights over the next several hours.
Then he wants to do a loop of the field to give the photographers a shot
of the AirScooter from below. But a pin shears off inside the engine at
startup, meaning another significant delay; the team will need to open the
engine again for repairs. As Phelps puts it, at this stage of development
it's virtually impossible to control for the "unk-unks" (unknown
unknowns). It will be nearly nightfall by the time they get the engine
fixed again. "Those unk-unks," Phelps says, "can really bite you."
Next day, a storm front descends, delivering thunderstorms, hail, and
near-gale-force winds. The tethered flight I'd been hoping to make is not
in the cards. I'm disappointed but, truth be told, not unhappy to wait for
the new four-stroke engine. Still, it was pure pleasure to watch Nolan
take the AirScooter up and around, precisely flying a helicopter with such
simple controls. The dream is alive here in this Virginia hay field.
Someday, one suspects, a lot of these babies will fly.
Seth Shulman's book Unlocking the Sky: Glenn Hammond Curtiss and
the Race to Invent the Airplane will be published in September.
May 2, 2002, 2:56 p.m.: AirScooter
pilot Jack Nolan achieves liftoff and circles a flight test area twice in a
3-minute demonstration for the Popular Science cameras.
Photograph by John B. Carnett
Easy does it: No fancy footwork
required: The AirScooter has footrests, not pedals; the exposed mechanics are
basic and sturdy.
Photograph by John B. Carnett
Easy does it: No
fancy footwork required: The AirScooter has footrests, not pedals; the
exposed mechanics are basic and sturdy.
Photograph by John B.
Carnett, Stylist: Vicky McGarry, Wardrobe by Bell Helmets, Flightsuits.com
With 2 pedals, throttle, and 2 control sticks, even pros find them tough to fly.
TAKEOFF (left): The pilot revs the engine until the main rotor reaches its set
rpm, then slowly raises the swash plate, which angles the blades in opposing
directions to create lift.
CRUISING (right): The pilot tilts the swash plate forward, changing the relative
angle of the blades. This creates more lift in the rear, propelling the craft
Illustration by Jason Lee
The right device for tight spots; staying upright is more of a challenge.
Computer control is the SoloTrek's trademark. The machine is propelled by a
120-hp engine and two ducted fans situated behind the pilot—one that spins
clockwise, the other counterclockwise. This complementary movement creates lift.
The pilot holds the throttle in his left hand. His right hand controls
direction: Moving it right or left directs a flap beneath each fan to tilt and
propel him in that direction. Moving it forward or back directs the fans
themselves to tilt. The computerized "stability augmentation system" ensures
that the fans, flaps, and ducts all move in sync.
Illustration by Jason Lee
AIRSCOOTER: Simplicity is the
mantra here. It's built to be cheap, light, reliable, and a cinch to fly.
Piloting the AirScooter is intuitive, thanks to a gimbal-based transmission. The
cab hangs from the rotors; to steer, the pilot merely points the handlebars in
the direction he wants to go. Water placed in the ballast tank balances the
engine's weight. The yaw paddles are fixed, but slant in tandem during a turn to
deflect the downdraft. The pontoons provide stability as well as safety.
Illustration by Jason Lee