SpaceShipOne, The Wright Flyer of Space Craft

by Dr. Richard Stimson

in Others

On the beautiful morning of June 21, 2004, some 100 years after the first flight of the Wright Flyer, SpaceShipOne flew a short flight of less than 90 minutes into space 62 miles above the earth. It was one giant step for the entrepreneur spirit.

In 1903, the thought of people traveling in the air from city to city seemed impossible. Today space exploration, both private and public, is still just getting off the ground.

Rutan said, “today’s flight marks a critical turning point in the history of aerospace. We have redefined travel, as we know it. Our success proves without question that manned space does not require mammoth expenditures. It can be done by a small company with limited resources and a few dozen dedicated employees.”

Rutan, 61, a college educated aeronautical engineer, founded Scaled Composites in the early 1900s. He has a reputation for his innovative approach to aircraft design. His genius seems to lie in his ability to combine a number of unrelated innovations into one design.

His interest in airplanes started at an early age. He was a competition aero modeler as a teenager. Many people first heard of him when one of his designs, the Voyager, flew around the world nonstop on a 9-day flight. Dick Rutan, Burt’s brother piloted the plane in 1986.

SpaceShipOne started its flight attached underneath the belly of another one of Rutan’s unique planes he developed from scratch, named the White Knight.

Using a mother ship reduces the expense and danger of a rocket launch from the ground.

The White Night took off from a normal runway witnessed by thousands of spectators who lined the grounds of the Mojave Desert Airport. The two vehicles joined together looked like something out of a Buck Rodgers comic book.

The twin turbo-fan powered White Knight carried the SpaceShipOne up to approximately 50,000-feet altitude to start the space flight. At that altitude they are through about 85% of the earth’s atmosphere. (Note: Cruising altitudes for some jets is 35,000-feet).

The pilot of SpaceShipOne was Michael Melvill. Melvill was born in South Africa and later became an U.S. citizen. He has worked for Rutan for 26 years and has flown all kinds of airplanes.

When SpaceShipOne disconnected from the mother ship, it glided for about 10-seconds while Melvill trimmed the craft ready for the rocket boost. He then threw a switch that fired the rocket motor capable of generating 17,000-pounds of thrust that accelerated the craft to twice the speed of sound.

This unique rocket motor was designed from scratch by Rutan’s design team. They had never made a rocket motor before just as the Wright brothers designed and built their own original 12-hp engine for the Flyer.

The rocket fuel consisted of tire rubber as the fuel and laughing gas as the oxidizer. The laughing gas self-pressures at room temperature, eliminating the need for the complicated systems of pumps and pipes typical in rocket engines. This saves money and weight.

When the rocket motor fired, Melvill immediately commenced a pullout maneuver to point the nose vertically in order to fly straight up to sub-orbital space. The craft continued to accelerate straight-out for a minute or so until the rocket burned out at about 150,000-feet. At this point the craft was going twice the speed of sound, straight out and coasting. The pilot felt about 3-4 g’s.

From there it coasted another some 150,000-feet until it reached apogee, about 62-miles above sea level.

Unfortunately, during this phase a control problem developed. The Wright brothers also encountered control problems on December 17, 1903. They had great difficulty maintaining pitch control.

After motor ignition, Melvill’s craft rolled to the left and then rolled to the right and experienced trim problems as the craft hit horizontal wind shear. To make matters worse, he experienced a temporary failure of the left stabilizer trim motor. The failure was caused by the trim motor reaching the stop and blowing its circuit breaker, which automatically reset itself in 3 seconds.

He had to fight to stabilize the craft. He said later “It never ever did that before.” He said he thought, “he was going to be a squashed bug.”

He briefly considered aborting or trying a high-risk bailout. He quickly dismissed that thought because a bailout would have destroyed the craft.

Fortunately, the craft had built-in backup controls. He switched to them and was able to regain mastery of the controls.

Because of the control problem, the craft varied from its planned trajectory and the apogee occurred at 328,491-feet instead of 360,000-feet. It was still good enough to reach the threshold of space of 62-miles.

Just before apogee, the craft was reconfigured for the next phase. Melvill flipped a switch that started a very unusual and clever procedure. The switch activated pneumatic actuators that moved the tail and back half of the wing and reconfigured the craft into a “jack-knifed position” for re-entry into the atmosphere.

The transformation took 15-seconds and the back half of the craft moved up 65 degrees.

In this configuration the craft acts as a stable badminton shuttlecock as it follows a ballistic trajectory through the apogee and starts its fall back to earth. At this point the pilot has no control.

This hinged or “feathering” wing configuration is the most innovative feature of the craft’s aerodynamic design. It provided a rock-solid stability at supersonic speed.

As the craft passed through the apogee, it picked up speed from zero as it fell back into the atmosphere. Melvill experienced weightlessness for about 3 1/2 minutes.

He had smuggled a package of “M and Ms” on board. He opened the package and let them go. “They stayed there spinning like little satellites.”

The craft fell towards earth into denser and denser air. The “jack knifed” craft presents to the atmosphere its full whole belly and the tremendous drag it created slowed the craft as it fell.

He experienced about 5 – 6 g’s during the deceleration. Only an experienced pilot, like Melvill, could remain conscious at these g’s.

Melvill experienced another potential problem. He heard some disconcerting loud rumbling noises in the engine area and shaking during this phase.

During the fall, only moderate heat was generated from the graphite-epoxy composite materials of the craft. Some hotter sections were treated with trowel-on ablative thermal protection. The insulation material worked as designed to protect the craft from the 1,100-degree temperatures of reentry.

As Melvill neared 50,000-feet, he flipped a switch and the craft turned back into the normal configuration with a tail.

He dived out of that maneuver and began a peaceful ride, flying the craft as a normal glider. He was back at the airport for a perfect three-point landing in 10 to 15 minutes.

When Melvill got off the plane he said, “It was like nothing I’ve seen before. You really do get the feeling that you’ve touched the face of God.”

He wore a good luck charm in the shape of a horseshoe on the left side of his spacesuit. He had given it to his future wife when she was still a teenager. She gives it back to him to wear for every flight.

Astronaut Buzz Aldrin of Apollo fame greeted him with “you have joined the club.” The FAA presented him with the first commercial astronaut wings.

SpaceShipOne is designed for sub-orbital flight that begins at 62-miles altitude. It holds three people, has a wingspan of 16.4-feet and is 28-feet long. The aspect ratio of the wings is 1.7. It utilizes elevons, which is a combination of ailerons and elevators, for control. The craft is less than ¼ the size of the Space Shuttle.

The craft uses its tail and wings to fly like an airplane during the ascent stage after horizontal launch from the mother ship and again during the gliding approaches and landing.

It cost $20 million dollars to build. Rutan claims that is about what it costs NASA to make a paper study. Investor and philanthropist billionaire Paul G. Allen, co-founder of Microsoft, is the major investor.

Samuel Langley had a government contract for $50,000 in addition to use of the resources of the Smithsonian and failed when his Great Aerodrome crashed twice on takeoff in 1903. The Wright brothers were successful a few days later using only $1,200 of their own money.

Rutan’s group will win $10 million if they can win the “X Prize.” To do that they must fly into space twice with the same craft within a two-week period carrying three people or equivalent.

There are 26 other ventures from seven countries that are also vying for the prize. One other team is reportedly close to attempting their first space flight.

The prize was established eight years ago for purpose of encouraging development of commercial space flight. A St. Louis group sponsors the prize. Erik Lindbergh, the grandson of Charles Lindbergh that flew from New York to Paris in 1927, is part of the group. SpaceShipOne’s flight is somewhat akin to Lindbergh’s pioneering flight that won the $25,000 Orteig prize.

The problems uncovered during the test program have been diagnosed and fixed. Rutan says they plan to fly again on September 29th followed by a second flight as early as October 4th.

One of the first commercial uses of SpaceShipOne will be for tourism. At first it will cost between $30,000-50,000 to experience the exciting ride and spectacular view. Melvill says it is a “mind-blowing experience.”

Rutan expects the cost to come down to around $12,000 with 5-6 passengers within about 15 years.

When the Wright brothers flew, there were few people who could imagine the impact that their flight would have on the 20th century. The commercial airplane industry and intercontinental flight seemed far-fetched. Even the brothers thought that governments would be their main customers because they were the only ones that could afford to buy their airplanes.

Rutan expects his efforts will spark the imagination of a new generation of explorers and new industry of privately funded manned spacecraft just as Orville and Wilbur opened the door to flight itself. The incentive of commerce will eventually lead to cheap access to space.

Up Date: Northrop Grumman buys SpaceShipOne Maker. A spokesman for Northrop Grumman said that Scaled will continue in its current operating model as a separate entity within Northrop Grumman and that Rutan and Scaled management will remain in place. The partner ship between Scaled and the Virgin Group, which seeks to begin  suborbital tourist flights in 2009, remains unchanged.

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