By BRADLEY S. KLAPPER, Associated Press Writer Bradley S. Klapper, Associated
Press Writer Wed Apr 7, 3:54 pm ET
PAYERNE, Switzerland At the pace of a fast bicycle, a solar-powered plane
took to the skies for its maiden flight Wednesday, passing an important test on
the way to a historic voyage around the world a journey that would not use a
drop of fuel.
The Solar Impulse lifted off from a military airport at a speed no faster than
28 mph (45 kph) after briefly accelerating down the runway. It slowly gained
altitude above the green-and-beige fields and eventually faded into the horizon
as villagers watched from the nearest hills.
"There has never been an airplane of that kind that could fly never an
airplane so big, so light, using so little energy. So there were huge question
marks for us," said Bertrand Piccard, who is leading the project. In 1999, he
copiloted the first nonstop round-the-world balloon flight.
During Wednesday's 90-minute flight, the plane completed a series of turns by
gently tilting its black-and-white wings, which are as wide as those of a 747
jumbo jet. It climbed nearly a mile above the Swiss countryside. The weather
was sunny, and there was little wind obvious advantages for a plane so light
and dependent on the sun.
Engineers on the $93.5 million (euro70 million) project have been conducting
short tests since December, taking the plane no higher than 2 feet and flying
no more than 1,000 feet in distance. A night flight is planned before July, and
then a second plane will be built based on the results of those tests.
That plane will be the one to attempt the round-the-world flight planned for
2012.
Click image to see 'Solar Impulse' in action
AP
"The goal is to fly day and night with no fuel. The goal is to demonstrate the
importance of renewable energies, to show that with renewable energies we can
achieve impossible things," Piccard said.
Aviation experts said they see a future for renewable fuels in commercial
aviation, but they predicted that biofuels from plants, algae or other sources
were more likely to succeed than solar power.
"Solar energy does not have enough 'energy density' to power regular airplanes
that are supposed to fly somewhere in a reasonably short time," said Hans
Weber, president of San Diego-based aviation consulting firm TECOP
International, Inc. With solar planes, "the objective is only to stay aloft,
not to go anywhere fast."
Test pilot Markus Scherdel said Wednesday's flight proved that the plane could
take off and land safely and handles like a passenger jet.
"Everything worked as it should," he said.
While the next plane will have an outer shell, the current prototype has an
open cockpit sort of the aeronautic version of a convertible.
Scherdel said the frigid air didn't bother him and that it was "too cold for
flies" that might otherwise have hit his face.
"I was wearing my special underwear and a windproof overall," he said. "I got
shoes and gloves with built-in heating. You see, we thought of everything."
Using almost 12,000 solar cells, rechargeable lithium batteries and four
electric motors, Piccard and co-pilot Andre Borschberg plan to take the plane
around the world. They will make regular stops to switch places and stretch
after long periods in the cramped cockpit and to show off their aircraft.
The circumnavigation will take time. With the engines providing only 40
horsepower, the plane will perform like a moped in the sky, at an average
flight speed of 44 mph (70 kph). The trip will be divided into five stages
keeping the plane in the air for up to five days at a time.
Solar flight isn't new, but Piccard's project is the most ambitious.
In 1980, a fragile ultra-lightweight experimental solar plane called the
Gossamer Penguin flew short demonstration flights with one pilot on board. A
bigger project called the Solar Challenger flew a single pilot from France to
England in 1981 in a trip lasting more than five hours.
Solar plane technology recalls the early days of manned flight, and the slow
ascent of the Solar Impulse was somewhat reminiscent of the Wright brothers'
pioneering experiments in 1903.
Wilbur and Orville Wright also progressed from short hops to longer flights
after 1905, reaching average speeds above 30 mph (48 kph) and only slightly
slower than the Solar Impulse.
The loud clicks of the Swiss plane's four propellers added another hint of
nostalgia. And designers acknowledged the same worries that preoccupied the
first fliers.
"The first crucial question was: Do we have enough power to fly?" said
Borschberg. "The second crucial thing was: Are we capable of landing this
airplane, is it controllable?"
"It was two hours of deep emotion," he added, calling the test flight the high
point of seven years of work on the project. "The airplane has landed but we
have not yet landed."
Borschberg followed the flight in a helicopter. Below waited numerous people
involved with the project and Piccard, who comes from a long line of
adventurers. His late father, Jacques, was an oceanographer and engineer who
plunged deeper beneath the ocean than any other man. His grandfather Auguste,
also an engineer, was the first man to take a balloon into the stratosphere.
On Wednesday, the Solar Impulse reached an altitude of 5,500 feet. After a
gentle landing, Scherdel emerged from the cockpit with his arms raised, and the
team broke open bottles of champagne.
When the plane attempts to circle the globe, the team will have to monitor
conditions closely to ensure the aircraft follows the best weather. Ground
crews will stay close to provide service at each stop, he said.
"Round-the-world will seem impossible until we do it," Piccard said. "Today is
an absolutely incredible milestone."