http://www.landings.com/_landings/pacfl ... er-un.html
Around the World, With 13 Fuel Tanks and a Single Seat
> >
> > November 30, 2004
> > By MATTHEW L. WALD
> >
> > EDWARDS AIR FORCE BASE, Calif. - Outsiders look at the
> > GlobalFlyer, a single-seat airplane designed to make the
> > first solo, nonstop, unrefueled flight around the world,
> > and wonder how a pilot could function for 70 hours in a
> > cigar-shaped cabin so snug he cannot even get out of his
> > seat.
> >
> > But the pilot, Steve Fossett, has another problem in mind:
> > fuel.
> >
> > Technicians at Scaled Composites, the company that built
> > the plane, like to call it the Flying Fuel Tank. At takeoff
> > - on Jan. 4 or as soon thereafter as the weather permits -
> > it will weigh as much as a 50-seat commuter plane. If it is
> > successful, it will land nearly three days later weighing
> > less than a medium-size S.U.V.
> >
> > On a recent test flight here it did not so much take off
> > like a jet (which technically it is) as glide into the sky.
> > Fully loaded, it will need more than two miles of runway to
> > lift off.
> >
> > The GlobalFlyer is first of all a feat of engineering -
> > building a plane strong enough to climb into the sky with
> > so much fuel and efficient enough to fly almost 20,000
> > miles without refueling. It is also a test of the pilot's
> > skill and of human endurance.
> >
> > Mr. Fossett, glider pilot, sailor and balloonist, is being
> > sponsored by Virgin Atlantic Airways, whose name is pasted
> > prominently on the ungainly GlobalFlyer. Scaled Composites
> > of Mojave, Calif., also built the Voyager - the two-seat
> > propeller-driven plane that went nonstop and unrefueled
> > around the world in 1986 - and SpaceShipOne, which took
> > home the $10 million X Prize in October for the first
> > private flight into space.
> >
> > The Voyager, it turned out, was almost too fragile to
> > complete the trip: when the Smithsonian took it apart to
> > get it into the Air and Space Museum on the National Mall
> > in Washington, technicians found cracked flanges in the
> > main spar, the backbone of the wing. (The plane hangs above
> > the information desk at the main entrance to the museum.)
> >
> > But technology has changed since then. The carbon-fiber and
> > epoxy material is about the same, said Burt Rutan, the
> > company's founder and the planes' designer. But the main
> > spar of GlobalFlyer, which is 110 feet long, is all one
> > piece, built at near room temperature. In the 80's,
> > composites had to be cooked in an autoclave, making such
> > big pieces impossible.
> >
> > The wingspan is about the same as that of a Boeing 737-900,
> > but there the similarity ends. The oddest part about the
> > GlobalFlyer is what engineers call the "fuel fraction,"
> > which is the percentage of takeoff weight that is in the
> > fuel. Lately the GlobalFlyer breaks the fuel fraction
> > record with each new test flight, but on its
> > round-the-world attempt it will be at its most extreme
> > ratio, 82 percent fuel. In contrast, at maximum takeoff
> > weight the 737-900 is 24 percent fuel, with a range of
> > 3,160 miles.
> >
> > The GlobalFlyer has a system of 13 separate fuel tanks.
> > Managing them is essential to minimizing wing bending and
> > keeping the plane balanced during its metamorphosis from
> > lumbering tanker into featherweight.
> >
> > A pilot of Mr. Fossett's skill can handle that transition,
> > the engineers say. But he will need more than skill.
> >
> > While the plane has an autopilot to maintain heading,
> > course and altitude, it still needs work before the flight.
> > No pilot can stay alert for 70 straight hours and, as Mr.
> > Rutan put it, "No one's willing to sleep with the autopilot
> > yet." In a single-seat airplane, sleep is a serious
> > problem.
> >
> > The Federal Aviation Administration, concerned about a
> > groggy pilot in the last stages of the flight, is
> > considering ordering that the plane take off from Edwards,
> > so that the flight's final hours, with the exception of the
> > last few minutes, will be over uninhabited ocean. But
> > mission planners are leaning toward an old air base in
> > Salina, Kan., with a suitably long runway, so that if the
> > fuel runs out 1,000 miles short of the destination, the
> > GlobalFlyer will be over land.
> >
> > The plane is supposed to cross the North Atlantic, Europe,
> > the Persian Gulf, India and the Pacific, but the route
> > could be changed during the mission, depending on weather
> > forecasts. The cruising altitude is above most of the
> > weather, but not all of it. And to save fuel, the climb to
> > cruise will be a leisurely 12 hours; descent will also be
> > slow.
> >
> > But time aloft is so long, and the cruising altitude so
> > high, that the designers switched from ordinary jet fuel to
> > a mixture that is less prone to freezing.
> >
> > For Mr. Rutan, the GlobalFlyer is an audacious attempt to
> > one-up the Voyager, another of his creations, which his
> > brother Dick flew, with another pilot, Jeana Yeager. That
> > was about 72 percent fuel at takeoff.
> >
> > Under rules laid out by the international federation that
> > keeps aeronautical records, "round the world" means at
> > least the distance around the Tropic of Capricorn. The plan
> > for GlobalFlyer is 19,864 nautical miles, or 22,859 statute
> > miles. The Voyager did 24,900, which is just short of the
> > distance around the Equator.
> >
> > This time the plane will use a single jet engine, the same
> > type used as half the power plant for corporate jets. The
> > engine will run during most of the flight well below its
> > ordinary cruise setting, the designers say. Mr. Rutan says
> > jets are so reliable that "it's safer to fly over a long
> > ocean with one turbo-fan than two piston engines."
> >
> > If it quits at 45,000 feet, or about 9 miles, finding a
> > landing spot is probably not a problem, because it can
> > glide about 30 feet for each one foot loss in altitude,
> > giving it a range of nearly 300 miles before the pilot
> > would have to land, ditch or bail out. But the GlobalFlyer
> > is such a wonderful glider that it would be a challenge to
> > descend fast enough to find breathable air.
> >
> > The reason is that to maximize its cruise efficiency, and
> > maintain a "clean" wing with as little drag as possible, it
> > has no spoilers, the wing-top devices that are used to
> > reduce lift when the plane has to land. It also lacks
> > flaps, the devices at the rear of the wing that extend to
> > provide extra lift at takeoff.
> >
> > And to save weight, the Flyer lacks most of the safety
> > devices common to modern planes. It has no deicing system
> > for the wings or windows. It has no radar to spot weather
> > or other traffic. It barely has brakes; engineers removed a
> > rotor from each disc brake.
> >
> > "In order to build a plane light, you have to build it with
> > very little safety margin," said John Krueger, a mechanic
> > and composite fabricator, standing amid the yucca bushes
> > and jack rabbit tracks at the edge of the 15,000-foot
> > runway at Edwards Air Force Base, watching the liftoff of a
> > test flight on Nov. 17. "When it's this heavy, the margin
> > is very small," he said.
> >
> > Even the emergency oxygen supply may be too small to keep
> > the pilot alive if the cabin depressurizes at cruise
> > altitude. A bigger system would weigh 12 pounds more, and
> > Mr. Fossett, 60, said he was not sure that it was worth the
> > weight. "A friend of mine suggested I go on a diet," he
> > said. (He put his weight at 213 pounds.)
> >
> > The Flyer looks like two planes flying in close formation.
> > Mr. Rutan designed it with two huge booms, each with a tail
> > at the back; the huge wing; and a small fuselage in the
> > middle.
> >
> > It is almost a single-use airplane, although Mr. Fossett
> > said he might fly it again after a round-the-world trip.
> > While new airliners use increasing amounts of composite
> > materials, aviation experts say that the Flyer probably
> > does not advance the technology they use. It could break
> > new ground that would be useful for other kinds of planes,
> > though, including high-altitude drones sent aloft for long
> > periods, for communications, surveillance or other
> > purposes.
> >
> > Mr. Fossett, interviewed by telephone from South America,
> > where he was seeking to set new records in gliders, said he
> > looked on the trip mainly as a piloting challenge. He said
> > the autopilot was coming along as Jon M. Karkow, the
> > project engineer and main test pilot, got more experience
> > with the plane, but added, "If I'm having trouble with the
> > autopilot, then I will absolutely not fall asleep."
> >
> > Scaled and Virgin refused to discuss the cost of the
> > mission.
> >
> > "I wonder if the Smithsonian will take it," said one Scaled
> > technician, Clint Nichols, watching it take off.
So, you have trouble. We all have trouble. Build a bridge and get over it.
Edited by - 30mike-mike on Nov 30 2004 10:45 AM
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