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Pictured is the Graceful Bird - the German-made DG500 sailplane.

Flying High

Riding the polar vortex, a surging but elusive wave of air, and soaring to 100,000 feet in a sailplane, is the latest adrenaline-fueled challenge to capture the imagination of American adventurer and Chicago native, Steve Fossett. The Chief Engineer’s intrepid reporter from “down under”, David Killick, caught up with the Fossett team in Omarama, New Zealand - one of the few places in the world where such a flight is possible. As he reports, the flight attempt is a formidable technological and scientific challenge: it also requires a dose of good old-fashioned grit and good luck.

How high is up? Drive 20 miles in any direction over land and you will end up in a city, the suburbs, or out in the country. Head 20 miles straight up and the air is so thin it can’t support life. That’s it. Space really is “the final frontier”.

Reaching the limits of the upper atmosphere in an airplane is still an amazing technological achievement; doing the same thing in a sailplane, with no motor at all, presents a whole bunch of new challenges.

Omarama, in New Zealand’s South Island - a name that means “place of light” - is one of only a handful of places on earth where such a feat is even feasible. It is ironic that just a few hours from here is the former home of Richard Pearse, a New Zealand inventor whose pioneer experiments with powered flight may well have beaten the Wright Brothers, and made him “the first to fly” (a story published in the December 2003 edition of The Chief Engineer.

Now it is Steve Fossett’s turn to make flight history. Over the last decade or so he has tallied up a list of firsts that look as if they come straight out of a boy’s action hero storybook, all of them defying the seeming notion that the age of adventure is over; Non-stop, around-the-world solo balloon flight, round-the-world yachting record in a catamaran, numerous other flying and yachting records.

This mission, called the Perlan Project, will also be a world first. (The name is taken from the Old Norse word for “pearl”, and refers to the “pearlescent” nacreous clouds that form in the upper atmosphere.)

In stage one of the project, Fossett and co-pilot Einar Enevoldson, a former USAF pilot and NASA test pilot, plan to beat the current world altitude record in a sailplane, of 49,000 feet set in California. Later, in stage two and using a new pressurized sailplane, they hope to soar to 100,000 feet.

This southern hemisphere winter provides the setting for what will be Fossett’s third attempt at the record. If successful, the team will also fulfill a decades-old dream for Enevoldson.

The project brings together the talent of a dedicated support crew prepared to stick together for the long haul, with no guarantee of immediate success. They include Einar Enevoldson’s wife and the project manager, Susan Conde; and from NASA, meteorologist Dr. Elizabeth Austin, avionics engineer Tom Wolf, and pressure-suite technician “Corky” Cortes, from the Houston Space Center. Local support from “scout” pilots is also invaluable.

Most commercial aircraft fly at about 36,000 feet. The celebrated U2 spy plane flies at about 74,000 feet. The highest anyone has ever flown in a conventional airplane, in steady flight, is about 85,000 feet, and that is at Mach 3 (three times the speed of sound). The reason that’s the limit? “The air’s too thin,” says co-pilot Enevoldson. “Basically, you have to fly faster through the air to get enough lift to stay up.” Other aircraft have flown higher, but their flight path has traced an arc-like trajectory. In June, the Burt Rutan-designed SpaceShipOne reached 328,491 feet. The X15 rocket plane has reached over 350,000 feet, traveling at Mach 6.

Fossett and team hope to fly their sailplane to about 62,000 feet - high enough to break the record, but also to prove that riding the polar vortex is possible. To fly to 100,000 feet, they would require a pressurized sailplane with different aerodynamics.

Atmospheric conditions must come into alignment at precisely the right time.

Sailplanes have been flying mountain waves ever since the 1920s. The waves have always been assumed to stop at the tropopause, usually about 36,000 feet, where commercial airliners fly.

Mountain waves, as the name suggests, are created by mountain ranges. They form only in certain weather conditions and require even temperature variations. One such New Zealand mountain wave is called “The Taieri Pet”, and can produce updrafts of 2,000 to 3,000 feet a minute. Last year, New Zealand pilots broke the world sailplane speed record riding the wave.

But there’s another wave of air, too: the polar vortex. And this is the wave that the Fossett team is pinning its hopes on catching.

High above Omarama in the winter sky above the Southern Alps, unseen as a phantom but as real as gravity, the vortex may be forming. It happens only at the winter, or the “night end” of the world. At 100,000 feet this wind can be strong - about 250 knots - faster than the jet stream. The vortex can extend up to 200,000 or 300,000 feet. In the southern hemisphere, the vortex reaches up as far as about 45 degrees South latitude - as far as the South Island of New Zealand.

A polar vortex also forms above the Arctic, but extends down only as far as 60 degrees North latitude. Near the equator the air is warmer, lighter, and rises at all altitudes. The air comes in a low altitude toward the equator from the poles. At very high altitude it flows from the equator to the poles. Imagine bands of air wrapping around the earth. At the summer end, the air warms but at the winter end the air cools and starts descending. As it descends over a rotating earth, this results in what scientists call a Coreolus acceleration of the air. Thus the polar vortex is born.

When the polar vortex and the jet stream are in alignment, there’s a continuous wind from the surface right up to the stratosphere. The mountain wave provides the initial lift. However, says Enevoldson, the waves “are not particularly correlated, so it’s just a matter of chance when they cross.” It may happen in the middle of the night or in a rainstorm. Riding the wave created by the polar vortex is so reliant on the ambient conditions being right, success is in the lap of the gods: the Fossett team has to be in the right place at the right time. The conditions in the lower atmosphere also have to be suitable for flying.

Finding the wave and riding it is the first challenge. Staying on it is another.

The wave may vary from a few hundred yards across to 20 miles. It’s invisible and constantly shifting. Lift rates may vary from those mentioned for the Taieri Pet mountain wave (30 knots vertical speed, 30,000 feet a minute, to 100 fee a minute.) The wave may surge, then die down again. “The time and the space and the shape shift all the time.”

“This is very frustrating, waiting for the proper conditions,” says Steve Fossett. “They’re very rare, we would estimate that there’s on average only about four days a year when this flight can be made, and last year there were zero days.”

Fossett will not stay in Omarama all winter. If the weather forecasts are good, he can fly his private jet from his home in Beaver Creek, CO, to reach New Zealand in two days. It requires, admits Fossett, being “extraordinarily patient.” But the man who tried six times before he succeeded in making a round-the-world balloon flight is not about to give up easily. “It will continue to interest me as long as we believe that we have a good game plan...so long as we believe in the theory that this can be done, I’ll probably stick with it.”

Argentina is another possible venue for a sailplane altitude attempt, but the infrastructure does not exist. (Omarama has previously hosted the world gliding championships, and is acknowledged as one of the world’s premier venues for gliding.) Flying in the Arctic winter was another possibility, but not surprisingly, with 24-hour darkness this did not seem so appealing to the Fossett team.

Adapting the sailplane for flight at stratospheric levels is the big engineering challenge. Aerodynamically and structurally, it is probably not possible to build a sailplane that will fly higher than 100,000 feet, believes Enevoldson.

Gleaming in the sunlight, “the bird”, with its 101-foot wingspan, looks impossibly delicate, graceful, and gossamer-light, the cockpit tiny. Riding it heavenwards on a wave of air will be truly akin to sailing on an ocean, relying completely on harnessing the natural elements, rather than raw power.

The German-made, two-seat DG500 sailplane was built originally as a self-launched motor glider, but the motor has been taken out. It has carbon-fiber wings, and has been certified for maximum carrying capacity.

As well as Fossett and Enevoldson, it must carry a payload of two military specification 10-liter liquid oxygen containers - sufficient for 14 hours - and lithium sulfur dioxide batteries that will tolerate the minus 20?C temperatures inside the craft.

Avionics engineer Tom Wolf, who usually works at NASA’s Houston Space Center, has made some items specially, some of which incorporate instrumentation from the SR71 Blackbird. Some items you would expect to find in a conventional sailplane, such as airspeed and altitude recorders and ELT (Emergency Locator Transmitter). Among other items onboard are primary and secondary navigation systems, with two GPS antennas and ATC (Air Traffic Control) transponders, two purpose-built outside air temperature probes, UV sensors, the TEP (Total Energy Probe), and NASA-designed atmospheric data recorders. There are also battery packs for gyro and faceplate heat. Most of the electronics are housed in an insulated box called “the igloo”. Data is displayed on a screen in the cockpit, similar to a Palm pilot.

As high-tech as a lot of this is, most of the displays are analog, not digital. Dual battery backup ensures reliability. In a chilly cockpit, a cozy minus 10 to 20, compared to minus 60 or 70 outside, instrument failure is not an option. Other modifications include double wall canopies for extra insulation to prevent fogging and icing up.

To fly in an unpressurized sailplane, the USAF has lent the Fossett team special pressure suits worn by U2 and SR 71 Blackbird pilots, and similar to those worn by astronauts. Each pressure suit costs $200,000 and weighs 20 pounds. The suit keeps your body at about 33,000 feet. It’s stiff, bulky, and unmanageable. But it’s vital. You die without it. Wearing it requires special training in an altitude chamber. Expelled breath and perspiration are extracted and dumped. An authorized NASA technician, “Corky” Cortes, who is also usually based at the Houston Space Center, has traveled with the suit, and a whole lot of bulky maintenance equipment. Corky’s role is to make sure the suit is always in perfect condition and is fitted properly. Just putting it on and “pre-breathing” takes two hours.

Once Fossett and Enevoldson are suited up, they can move their heads only about 15 degrees in either direction. At 35,000 feet, the suit will start to expand automatically, controlled by an aneroid pressure sensor. At sea level, air-pressure measures 14.7 psi; high up in the atmosphere it falls to only 3 psi. The suit will keep their body pressure about the same as it would be at 34,000 feet - about 5 psi. It has two backup systems. On descent past 35,000 feet, the suit automatically deflates.

Scientific applications of the flight are important, not just breaking the altitude record. Measuring the high-altitude wind field is one. Another curious discovery is that high-altitude mountain waves are related to ozone destruction. “There’s the potential to contribute to understanding the atmosphere, and that’s always a good thing,” says Enevoldson.

Technology plays a big part in the challenge, says Fossett. “It’s very different. It’s very technologically oriented. This is new meteorology. The meteorologists have only been dealing with this polar vortex, forecasting it, for about 25 years. This is pretty new information, and that the polar vortex will have this effect of creating the opportunity for a wave to continue well up into the stratosphere.”

NASA will also be interested in the Perlan teams’ findings. “At about 110,000 feet we’re getting pretty close to the density of the atmosphere of Mars - it’s thin. And this is one of the reasons NASA’s been co-operating with out project. It does provide them with more information on aerodynamics for flying in extremely thin atmospheres because we’ve been flying slow, so it does have some relevance to NASA’s interest in flying in the atmosphere of Mars. It has considerable relevance to the Air Force and NASA in flying high-altitude aircraft in turbulence.

Turbulence is a risk, he says, but not so much for the sailplane as it is for U2 pilots and similar research aircraft. Those aircraft are much more fragile. “Our glider is very strong. It will take between 5 and 8 gs of load without breaking, so we’re actually able to challenge these potentially very turbulent conditions by making this flight, and we’re able to plot the data, and learn more about breaking waves which may occur in the polar vortex.

Still, severe clear air turbulence (CAT) is a perennial concern, and the higher the sailplane flies, the greater the risk. The sailplane carries a drogue parachute fitted in the tail plane, just in case the pilots lose control. In the case, the ‘chute will help get them down to a safe level.

In an emergency, the pilots also have their own special parachutes, fitted with oxygen and battery units for faceplate heat. They would first plunge to about 33,000 feet supported by a smaller ‘chute; then barometric pressure would release the main ‘chutes.

From up high, the view is spectacular, says Enevoldson. Facing into the west towards the sun in the late afternoon can be “a battle”.

The longest flight will be about six hours. “You’re pretty tired when you get down; when you are up there you’re excited and you don’t notice it.”

Although the technology and science are fascinating, excitement is definitely a factor, says Fossett. “Yes, it is a grand adventure. Gliding in general is the most beautiful form of aviation and it’s really enjoyable flying gliders, and to try to fly higher than anyone has ever flown before is a big achievement.”

“I like to see the surprise on people’s faces when I tell them I want to fly a glider to 62,000 feet...first they ask, do you get a tow up there? Non-glider pilots are very shocked to hear that it’s possible to fly a glider up.”

Steve Fossett is proof that the age of adventure is still alive. “I come up with more ideas that I have time for...the most flattering congratulatory letters I get are from people who say that as a result of following my flight they’re doing some adventure on their own. I am actually quite pleased in having some influence on what people do. I don’t advocate that someone try to do the same thing that I’m doing, becuase those don’t fit, they maybe fit me, but they don’t fit somebody else’s circumstances.

What dirves him? “I started in Boy Scouts, age 11. I started climbing mountains on camping trips and its just continued on, and I’ve found this very interesting. I do it for my personal sense of accomplishment and fascination with the projects. I don’t do it to make money or to achieve any celebrity or anything like that. It’s mainly a personal thing and I like that, so I’ll just keep going.”

Fossett’s adventures have resulted in some hairy moments. “The balloon was very dangerous. Some high-risk landings. The balloon ruptred and fell from 29,000 feet off of Australia in the Coral Sea, and that was barely survivable.”

Another high-risk project is the Virgin Atlantic Global Flyer, in which Fossett wants to make the first non-stop round-the-world solo flight, without refueling. The attempt astonishes even veteran aviators. His specially built airplane, the Virgin Atlantic Global Flyer, will be virtually a flying fuel tank; 82 percent of the airplane’s takeoff weight will be fuel. “To make it non-stop is also a technological challenge to have an aircraft that can carry that much fuel.”

“This is unprecedented, and quite a design accomplishment, and it will also be an endurance test. It will take almost three days. I’ll be backed up with an autopilot, so that if I nod off or something, I’ll be fine, but it’s going to be a very difficult flight and there’s a lot of risk associated with it, too.”

The plane will take off either from Silina, Kansas, or Edwards Air Force Base, CA, for maximum takeoff runway along the dry lake bed. The challenge will take place between this December and March 2005, when the jet stream will give him maximum tailwind east to west.

For Einar Enevoldson, 72, a California native and a recipient of NASA’s exceptional service medal, the sailplane attempt is an enduring dream. “It’s a frontier. You don’t realize it, but up there 20 miles high is a frontier.”

Sailplanes were the very first aircraft he flew, after World War II. In half a century of flying, he has flown about 300 different types of aircraft. He served in the USAF for 13 years, including a stint as a test pilot seconded to the RAF, then flew as a test pilot for NASA. He has flown F86 Sabers, F104 Starfighters, British Lightnings, Hunters, and javelins, the U2, the SR17 Blackbird, the F14 - “everything you can imagine...well, things you can’t imagine.”

Some of the aircraft he flew for NASA looked like creations out of Thunderbirds. One was called a “lifting body”, kind of a father to the Space Shuttle, powered by a rocket. “More extreme than the Shuttle,” says Einar. “It was built as a proof of concept that you could land an airplane that had no wings.” Descent rate: 18,000 feet a minute on final approach.

Whoa!

After working for a German company he flew a spy plane called the Egret, but the project was cancelled after the Berlin Wall came down. “Probably the most interesting airplane I ever flew was a thing called the Strato 2C. It was built for atmospheric research, and the idea was to fly over the North and South Pole at 80,000 feet. They built it and we flew it. It was unique. It had lots of very advanced and completely new ideas.” The 25,000-pound, propeller-driven airplane had two 400HP engines, fitted with three-stage superchargers, and intercoolers. These allowed it to operate at sea level power up to 80,000 feet. With a 185-foot wingspan - longer than an Airbus A310 - it flew at just 55 knots. They got to 61,000 feet, but unfortunately, this project too was cancelled. “It was really challenging and interesting, and I feel bad that they never got a chance to finish the development.”

During this time, in the early 1990s, Enevoldson’s work led him to find out about the stratospheric wave, the idea to fly a sailplane to 100,000 feet. In the course of research, he found out about New Zealand, then in the late 1990s, met Steve Fossett, who became fascinated with the concept and eagerly lent his backing - not just financially, but physically.

Says Enevoldson: “We could break the record in California, but that’s not really the point. The point is to prove that we can get into the stratosphere, this upper structure that’s under the influence of the polar vortex, and if we do that then we say well, now we’ve proved that the idea is actually feasible so now let’s put some money into building a glider that’s capable of flying to 100,000 feet.”

The challenge continues.

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