balloon flight in 1999. Yves leapt from a platform on the side of the basket, stabilized the
wing, and completed two loops.
He is now working on an even lighter wing
that will bring empty weight down to 30
pounds and total weight to 100 pounds, including engines and fuel. Endurance will be
increased from six to 15 minutes. “It is brand
new, with a better weight distribution,” he
explained. And that’s not all. JetCat is developing new, more powerful engines for Yves that
the company expects will deliver 90 pounds of
thrust each. Yves expects the new engines will
provide a 1-to- 1 thrust-to-weight ratio, which
will enable vertical climbs.
And what about independent takeoff
from the ground? Yves feels it would be too
tricky. As with every wing, his needs sufficient airspeed to provide lift. Even with very
powerful engines, the launch from a standing start would be very unstable until the
airfoil reached sufficient airspeed. One consideration is the possibility of taking off from
an inclined ramp or a catapult. Yves does not
rule out anything, as long as the approach is
prudent and well founded in engineering. “I
am not a daredevil,” he said.
So could Yves’ wing take off from the ground
one day? With his current wing and engines,
he can attain launching speed from a fast-moving car. But it would take 90 seconds to
reach 2,600 feet, the minimum he calculates
he needs to be able to release his wing and
use his parachute with enough margin in
case of a mishap. However, Yves is working
with the company Parachutes de France to
design a parachute that will use ballistics to
deploy the chute—like the emergency recovery parachutes found on ultralight aircraft.
If successful, the safety altitude will be
reduced to 650 feet. Taking off from a car, it
would take 10 to 15 seconds to reach the
safety altitude. So the level of risk would be
no greater than that of a light aircraft on
takeoff, Yves pointed out.
HOW JETMAN FLIES HIS WING
So how does Yves fly his wing? There are no
control surfaces. No ailerons, flaps, rudder, or
elevator. An early version did have small ailerons, but the later versions do not. Control is
achieved through body movements. “To pitch
up, I arch my back. To pitch down, I bend my
body forward. To make a right turn, I tilt my
head to the right. To initiate a roll, I move my
shoulders,” Yves explained. He said that only
small movements are needed. The secret is
how the wing is installed and set on his back.
Before jumping out of the plane, helicopter, or balloon, he starts the engines and
brings them to idle. He then dives (rearward,
if from a helicopter or an airplane) from an
altitude of about 8,000 feet and is in a free
fall. At about 6,500 feet he stabilizes the
wing, and as he picks up speed, he gains lift.
“As soon as the wing provides enough
lift, I arch my back,” he explained. He
increases the throttle of the engines and
2600 ft 0 ft
70–90 mph 650 ft BEATING THE DEADMAN’S CURVE Yves is developing a smaller and more powerful wing that would allow him to takeoff from the ground. His current wing takes 90 seconds to reach 2,600 feet, an altitude safe enough to deploy his parachute. With improved engines and a ballistic parachute system, he hopes to reduce the time to 15 seconds and the altitude to 650 feet.
flies for about 10 minutes. Engine power is
controlled by a small potentiometer that
clings to a finger on his right hand, so
Yves’ hand retains its freedom of movement. There are almost no instruments,
just an audible altimeter that speaks his
altitude and has easily recognizable signals for warning altitudes that Yves sets
before each flight. Cruise speed is known
to be more than 130 knots.
In case one engine fails, the symmetrical
engine on the other side is automatically
shut down within one-tenth of a second.
“Otherwise the asymmetrical engine thrust
would initiate an uncontrolled roll,” Yves
explained. Two of the four engines generate
enough power to maintain level flight.
He flies with a combination of three parachutes: the main and reserve chute every sky
diver has, as well as a third parachute incorporated into the wing itself. When the fuel runs
out, he deploys his parachute and lands with
the wing still attached to his back.
“In theory, I should not have been able to
fly,” he said. “But I corrected instabilities
with instinctive body movements.”
That isn’t to say he hasn’t had his share of
mishaps. In 2004 at the Al-Aïn air show in
Dubai he went into a spin, released the wing,
and tore his parachute. A year later, despite
modifications to improve aerodynamics and
stability, uncontrollable oscillations again
forced him to release the wing, which crashed
to the ground. Yves estimated he has made a
total of 250 to 300 flights with the various ver-
sions of his wing and has had to release the
wing’s harness 25 times.
Maintenance on the flying wing also
involves maintaining Yves himself. “The idea is
to have the ‘landing gear’ working well,” he
quipped. He has no specific training program
but endeavors to keep in a good shape. “Skiing
is good for strength, mobility, suppleness, and
reflexes,” he insisted, not shrinking from the
fact that he will turn 52 this year.
SEEK FORGIVENESS, NOT PERMISSION
Another challenge in pursuing his activity
involves the civil aviation authorities. For
the initial, unpowered wing, the Swiss
Federal Office of Civil Aviation (FOCA) was
happy to greenlight Yves as long as he held
both parachuting and hang-glider licenses.
But the first trials of the powered wing
were another story. He fell back on the old
advice, it’s better to seek forgiveness after the