Category Space Ship One

Flying at 115 knots and 47,300 feet (14,420 meters), Pete Siebold detached from White Knight. Shown at the controls of SpaceShipOne in figure 7.10, Siebold became the second test pilot to fly SpaceShipOne. Mike Melvill had flown all the previous manned test flights.

Although SpaceShipOne’s performance was really starting to become dialed in, there was no shortage of work to do. Untested controls and the modified horizontal stabilizers needed evaluation— all this while Siebold learned how SpaceShipOne flew outside of the realm of the simulator. Figure 7.11 shows small strings attached to the horizontal stabilizer. With one free end, these strings helped the engineers identify how the air flowed over its surfaces.

Before Siebold completed the glide flight, he had to work on a new landing procedure that he and Binnie had been devising in order to improve reliability. “We had both very short, almost didn’t make it to the runway, and very long, almost off the end of the runway, landing excursions,” Doug Shane said.

Although SpaceShipOne glided okay, it didn’t have anywhere near the performance or control of a sailplane effortlessly gliding upward on the tops of thermals. The procedure involved overflying the run­way and hitting altitude waypoints while being able to accommodate coming into the approach too high or too low. After 19 minutes and 55 seconds in the air, SpaceShipOne landed at the intended aim-point.

Flight Test Log Excerpt for 8G

Date: 14 November 2003

SpaceShipOne White Knight

Objective: The fifth glide flight of SpaceShipOne. New pilot checkout flight. Stability and control testing with the new extended horizontal tails. Tests included stall performance at aft limit CG and evaluation of the increased pitch and roll control authority. Other objectives included additional testing of the motor controller (MCS) and handling qualities in feathered flight.

(source: Mojave Aerospace Ventures LLC, provided courtesy of Scaled Composites)

r >

Fig. 7.11. During Pete Siebold’s first flight, he had to evaluate additional modifications to the horizontal

stabilizers put in place to rectify handling issues revealed two flights earlier. Small strings attached to the newly enlarged horizontal stabilizers were used to help analyze the air flow. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

г-

Fig. 7.12. Mike Melvill returned to the pilot’s seat for the ninth flight, which was the sixth glide flight of SpaceShipOne. In the photograph, Melvill pulls a handle to his left to deploy the feather for additional evaluation. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

V______________________________________________________ ( ; ^

Fig. 7.13. An abort while fully fueled was a very big concern for Scaled Composites because

of the heavy weight for landing. Even when testing SpaceShipOne’s performance with ballast to more closely match the weight of a fully fueled rocket engine, it was necessary to dump the ballast prior to landing. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

V_________________________________________________ J f

Fig. 7.14. Among the biggest surprises to Scaled Composites was the difficultly of landing SpaceShipOne without undershooting or overshooting the runway. The test pilot had to manage the airspeed and altitude very carefully on approach to the runway for landing. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

Ґ

Flight Test Log Excerpt for 9G

Date: 19 November 2003

Flight Number Pilot/Flight Engineer

SpaceShipOne 9G Mike Melvill

White Knight 41L Brian Binnie/Cory Bird

Objective: The sixth glide flight of SpaceShipOne. Test pilot Mike Melvill’s first flight with the enlarged tails. Emergency aft CG handling qualities eval and simulated landing exercise with the new tail configuration. Airspeed and g envelope expansion and dynamic feather evaluation.

Scaled Composites received about $25 million from Paul Allen for twenty tasks that Burt Rutan had specifically outlined, which covered
building SpaceShipOne all the way through competing with it. “Task 21 was that we would fly SpaceShipOne every Tuesday for five months, reasoning that if we did that you could then make with confidence a commercial business plan,” Rutan said.

But Task 21 wasn’t funded. Rutan figured that once he got the data on the real costs of flying SpaceShipOne, he would then approach Allen. “That would be the opportunity for Paul and me and both of our friends to be astronauts,” Rutan explained. “If you just count only the passengers, you’ve got forty-four people. So, maybe twenty of my friends could be astronauts and twenty of his friends could be astro­nauts. That would be kind of cool. That was the plan. But something got in the way of the plan. I underestimated the impact of SpaceShipOne on the media and the public, and I underestimated its effect on historians.”

Shortly after Melvill flew SpaceShipOne into space the first time, Rutan received a letter from Valerie Neal, the curator of post-Apollo human spaceflight for the Smithsonian Institution’s National Air and Space Museum. “It was clear to all of us right away once Mike Melvill had made the first flight in June that this was a remarkable achievement, whether or not it won the Ansar і X Prize,” Neal said.

“We think that SpaceShipOne either itself may prove to be the pivotal craft that leads to a commercial spaceflight space-tourism industry, or it’s the leading edge of that. You know there are enough developments going on right now. It looks as if this is the cusp of a new revolution in spaceflight.”

So, the National Air and Space Museum expressed its interest in acquiring SpaceShipOne to join it with other remarkable vehicles in the Milestones of Flight gallery, which includes the original 1903 Wright Flyer, Spirit of St. Louis, and the Bell X-l that broke the sound barrier, Glamorous Glennis. But the National Air and

Ґ л

Fig. 10.11. When SpaceShipOne made it first spaceflight on June 21,2004, the National Air and Space Museum of the Smithsonian Institution immediately recognized the significance of the event. By becoming the first non­governmental, privately funded vehicle to reach space, SpaceShipOne earned a place in the Milestones of Flight gallery with the Spirit of St. Louis, Bell X-1, 1903 Wright Flyer, and Apollo 11 command module Columbia.

Courtesy of Virgin Galactic

Ґ Л

Fig. 10.10. On June 27, 2005, Burt and Tonya Rutan, in SpaceShipOne, and Mike and Sally Melvill, in White Knight, landed at Oshkosh, Wisconsin, for the Experimental Aircraft Association’s (EAA) 2005 AirVenture. An active EAA member, Burt Rutan introduced the VariViggen, the first aircraft he designed and built, at the 1972 AirVenture. Now he and Melvill, also a longtime EAA member, gave a special showing of SpaceShipOne and White Knight to many of their closest supporters. Tyson V. Rininger

V______________________________ J

Space Museum didn’t realize the extent to which Allen was involved. Rutan said that he would have to bring Allen into the dialog as well.

“So,” Neal recalled, “it was right at the end of November or early December when Allen and Rutan both said, ‘Yeah, we’re really interested

in donating this to the museum. Come on out and let’s talk and let’s have a look at it together.’”

Rutan had to face a tough decision. He explained, “When we got that request, Paul Allen called and said, ‘Listen, I don’t want you to fly it anymore. Just get the X Prize. Two more flights and

Ґ

Fig. 10.12. Carrying a small piece of SpaceShipOne, the space probe New Horizons, launched in 2006, races to the edge of the Solar System. The first mission ever to the dwarf planet Pluto, it will arrive in 2015. NASA/Johns Hopkins University Applied Physics Laboratory-Southwest Research Institute

V______________________________________________________________________________

that’s it.’ We had three or four motors, so we could have easily flown one more flight. My first thought was to fight with him. I said, ‘No, you’ve got to prove a business plan. If this is going to go on to the next step, you got to do this.’ And then I realized that he really was right.”

Preserving the legacy was more important.

Valerie Neal recalled, “What I had asked Rutan to do before he delivered it to us was to return it to its June configuration. After that June flight, before the X Prize flights, quite a number of decals were added to it, and the Virgin Galactic logo was added to it. And the appearance was considerably different.”

Even the dent in the engine fairing from that flight was put back. That’s how seriously Scaled Composites took her request. So, right after SpaceShipOne was hung in the museum, the damage drew some quick notice. “The director of the museum came in and said, ‘I hope we didn’t do that last night.’ And I said, ‘No, no, it came that way,’” Neal said.

However, even before being transferred to the museum, Rutan wanted to fly White Knight and SpaceShipOne to Oshkosh. He wanted to do something special for the Experimental Aircraft Association (EAA), which had stood by him from the time of his very first aircraft. With Mike Melvill behind the stick of White Knight and SpaceShipOne attached below, he flew from Mojave but stopped right before reaching the air show in Madison, Wisconsin, to pick up some very important passengers. Burt Rutan and his wife, Tonya, climbed into SpaceShipOne, while Sally Melvill joined her husband in White Knight.

They touched down at Oshkosh on June 27, 2005. “It was very emotional because it was like a homecoming for the triumphant sol­dier,” said Tom Poberezny, president of EAA. “And here was Burt coming home to an audience that truly appreciated what he did because they’ve grown up with him. They’ve appreciated every design innovation he has ever done, his successes, his failures, his trials, his tribulations.”

Figure 10.10 shows the EAA crowd gathered around SpaceShipOne andWhite Knight.

When the air show ended, Melvill took off with a small crew to head for Dulles Airport in Washington, D. C., after first stopping over in Dayton, Ohio, the hometown of the Wright brothers. But the adventure was far from over. White Knight doesn’t have very long legs. Its range is only about 500 miles (800 kilometers). When it reached

Dulles Airport, someone must have noticed White Knight carrying a missile-like object. “So, they turned us around and drove us away right in the middle of the approach,” Mike Melvill said.

“I said, ‘If you turn us around, we will run out of gas.’ And the air – traffic controller said, ‘I don’t care. Make a one-eighty and get out of here. I don’t want to see you again.’ And I said, ‘You need to get your supervisor because this has all been pre-briefed.’ Pretty soon the airline guys on the same frequency were saying, ‘Hey, come on. This is the guy delivering SpaceShipOne to the National Air and Space Museum.’”

Even after arrangements had been made with the airport and with the officials from the National Air and Space Museum on the ground, Melvill was denied. But he could always be counted on when the situation did not go exactly as planned. With almost no gas, he was able to land on a runway that wasn’t being used by the airlines. After detaching SpaceShipOne from White Knight and spending about an hour on the ground, Melvill lifted off in White Knight. The mothership had left its baby for good. Figure 10.11 shows SpaceShipOne in the Milestones of Flight gallery after the donation ceremony on October 5, 2005, hanging next to Spirit of St. Louis and Glamorous Glennis.

Although SpaceShipOne’s mission was suborbital spaceflight, it was actually able to completely break away from Earth’s gravitational pull. In 2007, a small piece of SpaceShipOne, aboard the space probe New Horizons, zipped by Jupiter on its way to a rendezvous with Pluto and its moon Charon. It will then continue on further to the edge of the Solar System into the mysterious Kuiper Belt, a region of space responsible for the demotion of Pluto from a planet to a dwarf plan­et after the discovery of a tenth planet. Launched in 2006, this is the first mission aimed at exploring these celestial objects. Figure 10.10 shows a conceptual drawing of the space probe on its journey.

In June of 2015, New Horizons and the SpaceShipOne fragment will have completed the interplanetary cruise phase on the way to Pluto. Earth will be 3.06 billion miles (4.92 billion kilometers) away when the closest approach occurs. Eleven years earlier, to the month, SpaceShipOne had first entered space, giving real hope to those with dreams of floating free in space.

A character in Clarke’s 2010: Odyssey Two, in summarizing what he expected from an upcoming space trip, simply stated, “Something wonderful.” By the time New Horizons actually reaches Pluto, that phrase will be invoked many times thanks to the accomplishments of commercial space travel that are to come.

A: SpaceShipOne Flight Data

Date Intended Mission SpaceShipOne Flight Pilot/ Flight Flight No.<2) Pilot Flight Time {minutes} Release Altitude (feet (meters)} Release Speed {knots} Top Speed {Mach}<b> Rocket Burn {seconds} Shutdown Altitude {feet (meters)} Apogee {feet (meters)} Maximum g-Force {G}<b> No.(2> Flight Engineer 1 ime {hours} 5/20/03 Captive Carry 01C 24C Pete Siebold/ Brian Binnie 1.8 7/29/03 Captive Carry 02C Mike Melvill 29C Brian Binnie/ Cory Bird 2.1 8/7/03 Captive Carry 03G Mike Melvill 19.00 47,000 (14,330) 105 30L Brian Binnie/ Cory Bird 1.1 8/27/03 Glided) 04GC Mike Melvill 31LC Brian Binnie/ Cory Bird 1.1 8/27/03 Glide 05G Mike Melvill 10.50 48,200 (14,690) 105 32L Brian Binnie/ Cory Bird 1.1 9/23/03 Glide 06G Mike Melvill 12.25 46,800 (14,270) 115 37L Pete Siebold/ Matt Stinemetze and Jeff Johnson 1.5 10/17/03 Glide 07G Mike Melvill 17.82 46,200 (14,080) 115 38L Pete Siebold/ Cory Bird and David Moore 1.1 11/14/03 Glide 08G Pete Siebold 19.92 47,300 (14,420) 115 40L Brian Binnie/ Matt Stinemetze 1.4 11/19/03 Glide 09G Mike Melvill 12.42 48,300 (14,720) 115 41L Brian Binnie/ Cory Bird 2.1 12/4/03 Glide 10G Brian Binnie 13.23 48,400 (14,750) 115 42L Pete Siebold/ Matt Stinemetze 1.3 12/17/03 Powered 11P Brian Binnie 18.17 47,900 (14,600) 112 1.2 15 (d) 67,800 (20,670) 3+ 43L Pete Siebold/ Cory Bird 1.2 3/11/04 Glide 12G Pete Siebold 18.50 48,500 (14,780) 125 49L Brian Binnie/ Matt Stinemetze 1.3 4/8/04 Powered 13P Pete Siebold 16.45 45,600 (13,900) 125 1.6 40 (d) 105,000 (32,000) (d) 53L Brian Binnie/ Matt Stinemetze 1.3 5/13/04 Powered 14P Mike Melvill 20.73 46,000 (14,020) 120 2.5 55 150,000 (45,720) 211,400 (64,430) 3.5 56L Brian Binnie/ Matt Stinemetze 1.5 6/21/04 Powered 15P Mike Melvill 24.08 47,000 (14,330) (d) 2.9 76 180,000 (54,860) 328,491 (100,124) 5.0 60L Brian Binnie/ Matt Stinemetze 1.6 9/29/04 Powered 16P (XI) Mike Melvill 24.00 46,500 (14,170) (d) 3.0 77 180,000 (54,860) 337,00 (102,900) 5.1 65L Brian Binnie/ Matt Stinemetze 1.6 10/4/04 Powered 17P (X2) Brian Binnie 24.00 47,000 (14,360) (d) 3.25 84(e) 213,000 (64,920) 367,500 (112,00) 5.4 66L Mike Melvill/ Matt Stinemetze 1.6 (a) C, G, L, and P denote captive carry, glide, launch, and powered, respectively, for the intended missions of SpaceShipOne and White Knight. A second letter in the flight number indicates the actual mission if different than the intended mission. (b) The highest value is given whether occurring during boost or reentry. (c) Flight aborted prior to SpaceShipOne separation from White Knight, so SpaceShipOne was not released. (d) Data not reported in Combined White Knight/SpaceShipOne Flight Tests provided by Scaled Composites. (e) The value of 84 seconds is used based upon the transcript of 17P.

В: Chase Plane Crews

scaping from Earth will not always be astronomically expensive; contrary to the impression created by a Saturn launch, the energy needed to reach space is remarkably small.

“About eight hundred pounds of kerosene and liquid oxygen, costing some twenty-five dollars, will liberate enough energy to carry a man to the Moon. The fact that we currently burn a thousand tons per passenger indicates that there is vast room for improvement.

“This will come through the space refueling, nuclear propulsion and, most important of all, the devel­opment of reusable boosters, or ‘space ferries,’ which can be flown for hundreds of missions, like normal aircraft. We have to get away, as quickly as possible, from today’s missile-orientated philosophy of rocket launchers which are discarded after a single flight.”

When I wrote these words in July 1969, the Apollo 11 astronauts were on their way to the Moon.* The Space Age was barely a dozen years old, and travelling to space required so much money and effort that only the governments of the richest countries could engage in it.

But the early years of space exploration were driven by different considerations: both national space agencies and TV networks seemed to love the massive firework displays at rocket launches. Indeed, witnessing a Saturn V take off could be a moving experience—if we overlooked the fact that it was a grandiosely wasteful way to travel anywhere (each Apollo mission cost around two hundred million in 1960s dollars).

So, even as I covered the Moon Landings for CBS television, I was already looking ahead to a time when space travel would make more economic sense. In my essay, I envisaged that the true Space Age would dawn sometime after 1985, “. . . and projects which today are barely feasible will become not only relatively easy, but economically self-supporting.”

I added: “The closing years of this century should see the beginnings of commercial space flight, which will be directed first towards giant manned satellites or space platforms orbiting within a thousand miles above the Earth’s surface.”

Well, in those heady days of Apollo, I couldn’t have anticipated all the detours and distractions of the 1970s that delayed our optimistic projections. Politics and economics have taken their toll, but looking back, I’m happy to note that I was off by only a decade or so.

Commercial space flight is now beginning to be technologically feasible and will soon become economically viable. The rise of citizen astronauts has already begun—this time, I doubt if politics can hold up progress because it is no longer so closely tied to the fluctuating interests and resources of national governments.

SpaceShipOne: An Illustrated History chronicles a key milestone in the race to take private citizens and pri­vate enterprise to space. It’s the story of how a group of determined and passionate aerospace designers— and their financiers—pulled off one of the most remarkable accomplishments in our conquest of gravity.

In that process, they won the ten-million-dollar Ansari X Prize founded by my friend Dr. Peter Diamandis to galvanize private enterprise and technological innovation in space travel. The prize was modeled after the twenty-five-thousand-dollar Orteig Prize, offered in 1919 by hotelier Raymond Orteig, to the first pilot to fly nonstop between New York and Paris. An unknown airmail pilot named Charles Lindbergh finally won this challenge in May 1927, flying a single-engine aircraft named Spirit of St. Louis. That feat won him instant fame and spawned the commercial aviation industry that changed our world beyond recognition.

And here’s an interesting coincidence. In 1987, I received the Lindbergh Award presented annually for those seeking a balance between technology and nature. The winner in 2000 was Burt Rutan, who went on to design SpaceShipOne with generous backing from Microsoft co-founder (and science fiction enthusiast) Paul Allen.

Burt and I are connected in other ways. I am intrigued to read that Burt’s boyhood imagination was sparked by watching Wernher von Braun on TV talking about the exploration of the Moon and Mars. Wernher was a good friend who took to diving on my suggestion—I told him that the best simulation of weightlessness was achieved underwater. And a few years ago I found out, from his long-time secretary, how Wernher had used my 1952 book, The Exploration of Space, to convince President Kennedy that it was possible to land men on the Moon.

While writing this, I came across Burt’s remark in Popular Mechanics (September 2007): “If we make a courageous decision like the goal and program we kicked off for Apollo in 1961, we will see our children or grandchildren in outposts on other planets.”

Fortunately, we need not rely solely on governments for expanding humanity’s presence beyond the Earth. The Ansari X Prize has succeeded in spurring commercial astronautics, and I hope governments will not stand in the way. I am following with much interest the emergence of a new breed of “astropreneurs” who are trying out new technologies, business models—and indeed, building a whole industry—without relying on government funding.

In that sense, space travel is returning to where it started: with maverick pioneers dreaming of journeys to orbit and beyond, some carrying out rocket experiments in their own backyards. Burt and his team have been a great deal more successful than Robert Goddard ever was in his lifetime (and, thankfully, no one is ridiculing Burt the way they did with Goddard).

Yet, today’s astropreneurs like Paul Allen and Burt Rutan are driven by the same spirit of enquiry, adventure, and exploration that sustained Lindbergh and Goddard. This, then, is the inside story of how citizens reclaimed space.

SpaceShipOne, with its landing gear retracted, was rolled on a dolly underneath White Knight and then raised using a hand crank. The top of SpaceShipOne attached to a two-point pylon that was mounted on the belly of White Knight. Two hooks inside the pylon, fore and aft, clamped onto SpaceShipOne, securing the vehicles together, as shown in figure 3.3. Heating ducts from White Knight to SpaceShipOne also ran through the pylon. The wings of SpaceShipOne were further secured by braces running down from White Knight. The clearance between the two was only a meager 1 foot.

The optimum time to launch from Mojave Airport was at day­break. Figure 3.4 shows a predawn preflight briefing, which reviewed the mission readiness and addressed any last-minute concerns. After White Knight, carrying SpaceShipOne, rolled out of the Scaled

r ; л

Fig. 3.3. SpaceShipOne attached to White Knight at several points. A pylon underneath White Knight housed two hooks that fit into two rings on top of SpaceShipOne. A brace between each set of wings also helped to stabilize SpaceShipOne and keep it from swaying back and forth. Mojave Aerospace Ventures LLC, photograph by David M. Moore

V__________________ J

г ^

Fig. 3.4. Early in the morning before each test flight, a preflight briefing was held so that the test pilots, ground crew, and Mission Control could review the details of the flight plan and receive updates on the status of the vehicles and the weather conditions. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V___________________________________________

( ; t

Fig. 3.5. White Knight and SpaceShipOne taxi to Mojave Airport’s Runway 30. Located less than eighty miles northeast of Los Angeles, Mojave Airport became the first inland spaceport and the first public spaceport licensed by the FAA. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V__________________ )

( ; >

Fig. 3.6. Inside Mission Control, the flight director, Doug Shane (seated

front row center), was the point person on the ground who communicated directly to the pilots aboard SpaceShipOne and White Knight during all phases of the mission. The Mission Control staff monitored all aspects of SpaceShipOne based on the instrument and video data transmitted by the craft. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

v___________________________________________ J

Composites hangar and final preparations were completed, the two vehicles taxied out to the runway. Figure 3.5 shows White Knight and SpaceShipOne getting ready for takeoff. Once in the air, White Knight headed 40 miles (64 kilometers) to a release box, an area that had been designated by the FAA.

Early in the program, the target for the separation altitude was

50.0 feet (15,240 meters). However, both the characteristics of the air, more specifically the density, and the performance of White Knight, or lack thereof, favored a separation altitude closer to

47.0 feet (14,330 meters). For this first stage of the ascent, White Knight spiraled up at a rate of about 700 feet per minute (210 meters per minute). And by the time the vehicles reached 45,000 feet (13,720 meters), the vehicles were above about 85 percent of the atmosphere.

“We fly up there on White Knight, and that is a really long period of time. It is close to an hour to get up there,” Melvill said.

“I really hated the ride up there,” he continued. “No one wants to talk to you. They think you need to sit there and concentrate on what you are about to do. I really would have liked someone to distract me and have a conversation about something else, because an hour is a long time to sit there and worry about what’s going to happen.

“You start getting close to the drop zone and close to the altitude. Then you go through a pretty extensive checklist setting the airplane up. You trim it 10 degrees nose up, so that when it drops off, it holds its nose up.”

Watching for the slightest abnormality, Mission Control carefully monitored the flight data and video transmitted by SpaceShipOne during the entire flight, as figure 3.6 shows.

It was possible to rotate the entire horizontal stabilizer on each of the tail booms. Adjusting it with 10 degrees nose-up trim would help ensure that SpaceShipOne didn’t go into a dive once it detached from White Knight. This setting was also necessary to help force the nose up once the rocket engine fired, enabling SpaceShipOne to move from horizontal flight to nearly vertical flight.

Figure 3.7 shows a close-up of SpaceShipOne during the captive-carry.

The procedure for the airborne launch of the rocket-powered second stage from the carrier aircraft was pretty simple. Even before the 1920s, flying vehicles had been dropped by larger flying vehicles. And NASA extensively used motherships for dropping X-planes and even for flight testing the Space Shuttle (refer to figure 3.8 and figure 3.9, respectively).

White Knight had to remain steady with its wings level. The pilot in SpaceShipOne began the sequence by arming part of his release system. In the cockpit of White Knight, a yellow light then came on. White Knight would arm next, giving another yellow light. At that point, the release handle inside White Knight became “hot.” A crew member in the backseat pulled it to retract the hooks. White Knight shook with a big bang as the spring-loaded hooks came to a sudden stop. SpaceShipOne dropped away as White Knight surged upward.

“There is an instant feel of you climbing,” said Pete Siebold about flying White Knight during this separation. “You lost almost half your weight. You were at 1 g and it jumped up to 1.6 g’s the second you pulled the release handle.”

Siebold flew SpaceShipOne three times, but all the test pilots pulled double duty when it came to flying. During flight tests with SpaceShipOne, one of the other SpaceShipOne pilots always flew White Knight.

г л

Fig. 3.8. Carried to a height of

45,0 feet (13,720 meters) by a NASA B-52, the North American X-15 dropped from the wing at a speed of 500 miles per hour (800 kilometers per hour). The X-15 would typically carry out one of two missions: high-speed hypersonic (faster than Mach 5) test flights or high-altitude test flights. NASA-Dryden Flight Research Center

V J

Г Л

Fig. 3.9. The Space Shuttle Enterprise launches from the top of a NASA 747 Shuttle Carrier Aircraft (SCA). During the test flight, Enterprise glided back down to Dryden Flight Research Center, so aerodynamic and control characteristics could be evaluated prior to an actual spaceflight. NASA-Dryden Flight Research Center

For safe separation from White Knight, as shown in figure 3.10, the pilot in SpaceShipOne pushed forward on the control stick. This briefly counteracted the trim setting on the horizontal stabilizer. So, instead of wanting to pitch up, SpaceShipOne dipped down to avoid re-contacting White Knight.

Gliding for about 10 seconds, SpaceShipOne grew quiet, since it was now out of earshot of White Knight’s engines. The pilot made some quick final checks with Mission Control.

“You have to get the motor started as soon as you possibly can because you are just teetering on the edge of a stall,” Melvill added. “You’ve got all
that rubber fuel at the back of the airplane.” The center of gravity for SpaceShipOne was very far back. If its nose pointed up too high, without the rocket engine going, a stall would develop that would cause the space­ship to lose aerodynamic control. A pilot could recover from this, but SpaceShipOne would have lost a good deal of altitude in the process.

hen SpaceShipOne touched down on Mojave’s Runway 30 after its third flight into space, it not only won the Ansari X Prize, but it also, in a way, completed a journey that had started on two separate paths that intertwined along the way and then finally merged together in 2004. SpaceShipOne was a small, lightweight rocketship somewhat resembling NASA’s early X-planes but with elements of Burt Rutan’s distinct flair for the unique and unconventional. Figure 1.1 shows Burt Rutan with Doug Shane, the test flight director, and the three SpaceShipOne test pilots, Pete Siebold, Brian Binnie, and Mike Melvill.

On that day test pilot Brian Binnie did more than capture the Ansari X Prize. He captured people’s imagination and reignited the space-crazy in them. Back in 1927, Charles Lindbergh, who just barely cleared telephone lines after takeoff in pursuit of the Orteig Prize, crossed the Atlantic Ocean nonstop from New York to Paris and sparked a boom in aviation like none other. These two turn­ing points forever changed the way people looked up into the sky and saw them­selves flying free as the birds or high as the stars.

Without people there would be no flying machines. It is not the mechanisms of engine, fuselage, wing, and empennage that provide transport into the air and through the clouds: it is the people whose ideas, visions, and daydreams have taken flight and soared. Without the human mind, the greatest height reached would only be as high as the highest surface that could be climbed.

г л

Fig. 1.1. Burt Rutan (top left), the SpaceShipOne and White Knight designer, and Doug Shane (top right), the test flight director, stand behind their test pilots, Pete Siebold, Brian Binnie, and Mike Melvill (left to right). Mojave Aerospace Ventures LLC, photo­graph by Scaled Composites

V___________ )

It is no coincidence that the breakthroughs in aviation have come from ingeniousness and inventiveness as early as Leonardo da Vinci’s drawings of flying corkscrews and birdlike flight suits, or even earlier when the ancient Greeks pondered the air around them. As ideas like these were being conceptualized, more often than not, peers would view such thinking as folly, insanity, or even sacrilege.

Thankfully, there are a few whose hides are thicker than most, whose resilience is more enduring than most, and whose passion burns brighter than most. And more importantly, there are some whose persistence in moving forward, even if it takes stepping back­ward at times, is unwavering. It is not enough to be a great thinker. The genius lies in the execution. As inventor Thomas Edison is famous for saying, “Genius is one percent inspiration, ninety-nine percent perspiration.”

But these factors are no longer enough in this day and age. In centuries past, it may have been sufficient for just one person to cultivate a dream, from beginning to end, into fruition. But in today’s ever changing, ever more complicated society, often a wheel with only one cog will not provide the grip needed to take hold of an idea and spin it into something magical. It is only when the sprocket has gathered enough teeth that it can truly turn and move forward in a synchronicity of movement.

Burt Rutan

In 1965, Elbert L. “Burt” Rutan found himself in the backseat of an F-4 Phantom trying to figure out how to regain control as the fighter jet whirled around in circles in an unrecoverable flat spin. At the time, the Phantom was one of the U. S. Air Force’s frontline fighters. Under the right set of conditions, though, pilots could enter a flat spin where the only way out required the use of their ejection seats. A total of sixty-one aircraft had been lost because of this, and Rutan’s job was to determine a way to recover from this disastrous condition.

Fresh out of college, it was certainly a dream job for someone who had craved a challenge. Born in Portland, Oregon, in 1943 and raised in Dinuba, California, southeast of Fresno, he had been flying model airplanes that he designed and built since he was a young boy.

“None of those things were kits,” Rutan said. “They were original designs.” He entered model-airplane competitions during high school while also learning to fly. His models took him to the nationals, and he brought home trophies.

“I was of course fascinated by space,” Rutan recalled. “I listened to the Alan Shepard flight on the radio as I was driving to my college to interview.”

Rutan attended California Polytechnic University, where he would receive his bachelor of science in aeronautical engineering. In 1964, he was one a very few students, the only one from his college, selected to attend the CalTech Space Technology Summer Institute. During this time the United States continued to lag behind the Soviet Union in the space race. Yuri Gagarin, aboard Vostok 1, had become the first man in space three years earlier, and it would be yet another five years until Neil Armstrong and Buzz Aldrin would set foot on the Moon.

The U. S. space program was hungry for engineers during this electrified time. It seemed natural that someone like Rutan would have his sights set on Apollo manned Moon missions.

Rutan remembers his boyhood imagination being stirred by watching television programs where Wernher von Braun, who headed Germany’s V-2 program but was now leading NASA’s Saturn V rocket development, talked about the exploration of the Moon and Mars with Walt Disney.

“Von Braun was a big hero of mine because of the Disneyland television show in 1955,” Rutan said. “Those programs were enormously compelling to me as a twelve-year-old because we didn’t know much about Mars in ’55. I have a college astronomy textbook that I had gotten a long time ago. It was written in ’53. It is interesting to read because they are debating what kind of life is likely to be on Mars and would there be a chance that it would be intelligent life. So, imagine yourself back in a time period when you believed there was vegetation there because you saw the colors change in the telescopes.”

Rutan had a tough decision to make when it came time to leave college. Although the space program barreled forward, and opportunities
certainly waited for him, he was very skeptical about how and where he would fit in. “I felt I was so far behind on being able to come in and take a new idea and actually get it out there flying if I focused on spaceflight or manned spaceflight.”

He didn’t want to work on the space widget of the what-cha-ma-call – it subsystem. While this obscure part was indeed a piece of the puzzle that would have been necessary for launch, Rutan desired to really make a big impact and influence the big picture. Working for an airliner or fighter manufacturer didn’t interest him, for the same reason. “I’d be working on a bulkhead or a door.”

So, he turned in another direction. “I thought I could make a big dif­ference with general aviation, which I thought was archaic and frozen.” He felt that he’d have the opportunity to let his creativity fly, even if it wouldn’t be quite as high as if he worked for the U. S. space program. But Rutan’s competitiveness helped sway him in yet another direction.

“I couldn’t bring myself to go work on Cessnas while everyone I went to school with was on the way to the Moon. So, I made a compromise. I went into air force flight testing.”

This was by far the best decision Rutan could have ever made. Working as a civilian at Edwards Air Force Base in Mojave and spending six to ten months on an aircraft before moving to the next one, he learned what risks to take and what decisions to make when testing out new aircraft. This education, he felt, was critical for a designer.

“I’m out there evaluating the performance, flying qualities, safety, etc., of the top-of-the-line, brand-new military airplanes. I got to fly in them, measure data, and report on their performance.”

In the Phantom on that day in 1965 when it went into a flat spin, once Rutan and the test pilot were sure that the flat spin was unre­coverable, they deployed a special recovery parachute that forced the large fighter jet out of the spin. “I’ve done the only flat spin in an F-4 that did not have an ejection.” But the very next flight, with a different test engineer in the backseat, the spin recovery chute failed, and both the pilot and test engineer ejected to safety. Rutan still keeps in his office a piece of the F-4’s canopy from the wreckage that actually has his name on it. Eventually a procedure would be devised using the Phantom’s existing landing drag chute, which greatly reduced the rate of unrecoverable flat spins.

Rutan left the air force in 1972. He explains, “Now I could really exercise with my own responsibility, my own authority, my own decision on risk taking with nobody to answer to in developing the VariViggen, the VariEze, the Defiant, the Solitaire, and all these homebuilts. That path could never have accelerated at that rate if I had gone into the space program.”

Clear of White Knight, the pilot armed the rocket engine, flicked the ignition switch, put his head back against the seat, and grabbed the control stick with both hands.

“When you light that rocket motor off, everything literally starts with a bang. There is so much energy associated with that rocket motor. It is like a tsunami sweeps through the cabin and literally takes you away,” said Brian Binnie, the pilot who flew the first and last powered flights of SpaceShipOne.

“You really have nothing in your background or DNA to tell you that what is happening to you is good. You have no basis. Three or four seconds will go by, and you go, ‘Ah, I’m not dead. Therefore, it must be going as they told me it was going to go.’”

The roar from the rocket engine was extremely loud. “The noise is certainly worse right at ignition when you have little forward speed,” explained Binnie. “But as soon as you are supersonic, you are going faster then any sound that the rocket motor makes. It doesn’t really penetrate the cabin a lot. What you hear in the cabin is all the gurgling off the main oxidizer tank that’s right on the other side of the bulkhead from which you’re located. So, you hear that. There is a certain amount of wind noise over the vehicle. A good helmet with reasonable ear protection let the radio come across just fine.”

The force pinning the pilot to his seat just added to the flood of sensations. “The acceleration is fierce. It’s abrupt. It’s sudden. It’s a big slap in the back and whoosh off you go. It is a very dynamic environment, and you are very much holding on for dear life,” Binnie said.

“As it develops, your body readily adjusts to the g’s that you are experi­encing. They are not that high during boost. They are between 3 or 4.” Having been a former navy fighter pilot, Binnie had some experience with some pretty fast starts. The initial kick from a catapult off the deck of an aircraft carrier had some similarity. After 2—2.5 seconds, the acceleration from the catapult was over, but after the same amount of time, SpaceShipOne would still be going and going.

“A catapult shot takes you from 0 to about 150 miles per hour [240 kilometers per hour] in 2 to 2.5 seconds. If you continue that accel­eration rate, which is kind of what the spaceship is doing, you would then go from 150 to 300 miles per hour [480 kilometers per hour] in another 2.5 seconds or the 5-second mark. And at the 8-second mark, you’d be doing not 300 miles per hour but 600 miles per hour [970 kilometers per hour]. And by the 10-second mark, you’d be supersonic.”

The pilot held the control stick with both hands because, as SpaceShipOne moved faster and faster, the forces from the outside air pushed harder and harder against the vehicle and its controls. The pilot had to make sure the nose was coming up right away. Otherwise there was a danger of overspeeding SpaceShipOne and breaking it apart. The “never-exceed” speed was around 260 knots equivalent airspeed (KEAS). A knot is a nautical mile per hour, which is a little faster than a mile per hour. Equivalent airspeed is a measure of how fast a vehicle feels it’s going in terms of the air pres­sure pushing against it. So, this value may seem very low, but SpaceShipOne started out already operating above 85 percent of the atmosphere. The air density was very low to begin with and didn’t exert as much air pressure as if the vehicle were flying at a lower altitude where the air density was higher.

Figure 3.11 shows SpaceShipOne during the initial pull up, also called “turning the corner” or the “gamma turn.” With the feather locked down tight, it was critical for the pilot to keep the wings level during this phase.

“Because our wings are level, that turn results in pointing nose up,” Pete Siebold said. “So, if any portion of the time you roll to a

ч

С “ ^

Fig. 3.11. Once the rocket engine ignited, the test pilot immediately had to begin to pull the nose of SpaceShipOne up in a maneuver called "turning the corner." By the time the turn upward was complete, SpaceShipOne was already traveling at supersonic speeds. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

V___________________________________________ )

non—wings level attitude, instead of going up, you are going to turn to a different heading and not go up. A significant amount of the energy is spent doing that initial turn.

“If there was any time spent non—wings level during this turn, you ran the risk of not making your ultimate goal of 100 kilometers [62.1 miles] at the end of the flight.”

A number of things caused the wing to wander back and forth. Asymmetries in the thrust from the rocket engine and asymmetries that resulted from supersonic shockwaves wanted to knock SpaceShipOne off course.

Melvill added, “And there are wind shears that exceed 100 miles per hour [160 kilometers per hour] going in different directions. So as you go up, it will blow you this way and then it blow you that way. You are not there for long, so you don’t get massive changes, but you are constantly correcting.”

By using an avionics system called the Tier One navigation unit (TONU), the pilot could ensure that SpaceShipOne was wings level and had the proper pitch rate, which was a measure of how fast the nose was rising. For the first 5 seconds, the pilot used the control stick and the rudder pedals to keep the wings level. “You can feel the forces start to build quite rapidly,” Binnie said. “And now your thinking is, ‘Okay, I’m going to keep fighting this thing physically until about 8 or 9 seconds, and then I’m going to transition over to controlling the vehicle with electric trims.’” To do this, the pilot took his left hand off the stick and reached for the rudder trim controller, a big black knob that looked liked a turtle shell.

Binnie explained, “As you are going through transonics, where the vehicle is shocking up asymmetrically, it is still rocking back and forth or more like whipping back and forth. Your job is to try to filter out the oscillatory motion and chase down with the turtle any longer-term disturbance that is driving the nose of the vehicle off trajectory.

“You have high-rate motions but you have a low-rate controller. So, things don’t happen as quickly as you’d like them to. You put in an

с ; ^

Fig. 3.12. Traveling close to vertical, SpaceShipOne’s hybrid rocket engine burned 76-84 seconds during a spaceflight. At rocket engine shutdown, SpaceShipOne was a little more than half the way up to apogee. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V__________________ )

adjustment, and you’re going to have to be patient to sort of see it take effect. And that is not the easiest thing in the world to do because you just had your brains scrambled. And everything about you is on high alert, and now you have to be patient and wait for the thing to respond. If you don’t, it is easy to over-control it, and you can get yourself into even more trouble.”

As the pilot was finishing the initial pull up, SpaceShipOne passed the rough transonic transition from subsonic to supersonic.

“You settle in around the 10- to 15-second mark and look out the window. And appreciate that you are no longer horizontal. The nose will appear vertical, but it is not quite there yet,” Binnie said.

г-

Fig. 3.13. Photographed from inside the cockpit of SpaceShipOne by Brian Binnie near the apogee of 367,500 feet (112,000 meters), the Channel Islands and the Pacific Coast peek through the cloud cover as black sky shrouds Earth. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V__________________________________________________________________________________________

Figure 3.12 shows SpaceShipOne and its contrail during the ascent to space.

As SpaceShipOne continued to ascend and slowly move its nose closer to vertical, the use of the control stick came back. The pilot could again use the mechanical controls to fly, even though it traveled much faster than Mach 1 and was still gaining speed. The air density was too low to create much opposing force but still high enough for aerodynamics to work.

At about the 1-minute mark, the rocket engine went through a liquid-to-gas transition. “This is kind of a wake-up call that you are getting near the end of the boost phase of flight,” Binnie said. “The vehicle shakes and shudders some more. And then the rocket motor valve that you are sitting not too far from has some unusual acoustics
associated with it. It sounds like riding along with a possessed cat. It kind of screeches and howls and complains.”

SpaceShipOne reached a maximum speed of Mach 3.09, or 2,186 miles per hour (3,518 kilometers per hour).This occurred just before burnout while it was still accelerating. But the atmosphere was very thin at this point, so the airspeed was only about 40 knots equivalent airspeed.

The highest altitude for rocket-engine shutdown occurred at

213,0 feet (64,920 meters). The burn lasted 84 seconds. Unlike shutdown inside the thick atmosphere, where thrust no longer kept the pilot pinned to the seat and the deceleration force flung him forward in his seat, shutdown at high altitudes was tame because of the thin atmosphere and because the rocket engine’s thrust had tapered off due to the longer burn duration. SpaceShipOne now coasted upward.

г

Fig. 3.14. During the 3.5 minutes of weightlessness, the test pilots were able to take photographs from inside SpaceShipOne’s cockpit. In this photograph, the red-colored thermal protection on the leading edge of the right wing can be seen through one of the porthole windows. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V__________________ У

“Three wonderful things happen/’recalled Binnie. “The noise goes away. The shaking, the shuddering, the vibration go away, and you become instantly weightless. And the weightlessness is just a pro­foundly exciting and pleasurable experience.”

“Then of course there is that view. You’ve seen it on the cover of magazines and things like that. But when you see it for yourself, it is really breathtaking. The eye is so much more dynamic than a video or a camera. It is yours for the enjoyment.”

As SpaceShipOne rocketed upward, light scattered less and less in the dwindling atmosphere. “You can already see the blue skies turning a much darker, deeper shade of blue and as you continue to watch that, it will deepen and darken and kind of go purplish and then to black,” said Binnie.

Figure 3.13 shows the black sky surrounding Earth in a photo­graph taken by Brian Binnie aboard SpaceShipOne. So where are the stars in the black sky? Above the atmosphere there should be stars galore. Well, they are there. However, a camera cannot catch the stars. Earth is much too bright. To see the stars in a photograph, a much longer exposure time is needed, but then the features of Earth would be totally washed out. This phenomenon can also be observed in the famous “Earthrise” photograph taken by the crew of Apollo 8 as they circled the Moon, where Earth is seen rising above the sur­face of the Moon and no stars can be seen in the background.

Following a ballistic arc, the unpowered spacecraft continued to climb, coasting up while the atmosphere dwindled away. To win the Ansari X Prize, it was necessary to reach an altitude of 328,000 feet (100,000 meters). So, as SpaceShipOne raced toward this height, the pilot enjoyed the effects of zero-g. Without the atmosphere, the drag
caused by the air resistance was no longer a factor causing SpaceShipOne to decelerate. Gravity still had a hold on SpaceShipOne, however, and the spacecraft was not traveling at a high enough veloc­ity to escape the pull of Earth.

Having taken an hour to reach launch altitude and separation, the max­imum altitude when SpaceShipOne reached the top of its climb, or its apogee, occurred about 3 minutes after the rocket engine initially fired off. SpaceShipOne stopped moving up at this point and began to free fall back to Earth. The pilot experienced weightless conditions for approxi­mately 3.5 minutes, which he started to feel once the rocket engine shut down. For comparison, the Space Shuttle took 8.5 minutes to go from its launch pad to its orbital altitude of around 200 miles (320 kilometers).

Shot from space, the photograph in figure 3.14 gives a glimpse from SpaceShipOne’s window of the leading edge of its wing high above desert mountains.

While outside the atmosphere, SpaceShipOne could not use its rudders or elevons to control movement whether it was ascending or descending. Since space is a vacuum, there was no air to provide the lift that these control surfaces required to change the spacecraft’s course. This is the same problem faced by the Space Shuttle, as well as other spacecraft and satellites. Even astronauts during extravehicular activity (EVA), floating outside the International Space Station, need a way to steer themselves around. To maneuver in space, they accomplished this by shooting little jets of gas in a direction opposite to that of the intended motion. So, for example, if a spacecraft needed to move to the right, it shot a puff of gas to the left.

SpaceShipOne was no different. In the airless environment, the pilot had to use the reaction control system (RCS) to maneuver SpaceShipOne.

г

Fig. 3.15. In an interview with Ed Bradley for 60 Minutes after the Ansari X Prize spaceflights, Burt Rutan shows the feather configuration and describes how it allowed the safe return of SpaceShipOne to Earth’s atmosphere. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

After he switched the RCS on, he used the control stick and rudder pedals to control thrusters mounted on the fuselage and wings.

“We chose to put a microswitch on the end of the travel, so you had to get your knees out of the way just to do anything at all. You had to move the stick all the way to a stop until it closed the microswitch, opened up a valve, and then the jet worked,” Melvill said.

The rudder petals worked the same way, in that they had to be pushed all the way on the floor to activate the thrusters. So, the thrusters would fire as long as the pilot pressed against the microswitches.

After working two years as the director of Bede Test Center for Bede Aircraft, makers of the BD-5J Microjet, Rutan was ready to go it out on his own. In 1974 he founded Rutan Aircraft Factory (RAF) to continue the development of his first airplane, which he began designing back in college and started flying in 1972, and the develop­ment of brand new designs.

“I name very few of my airplanes,” Rutan said. “Even the VariViggen, my first one, was named by a guy at work. I told him I was going to build something that was a lot like the Swedish Viggen, except that it had the feature of variable camber that changed the loading. He said, ‘Okay, how about VariViggen.’” Rutan simply replied, “Okay.”

Although Burt Rutan is well known for the use of composites, the VariViggen’s only use of composites was a fiberglass cowling. The aircraft was made out of wood, and its wings were aluminum. However, it had what would become a hallmark of Rutan’s—a canard. The canard was a small wing forward of the main wing that enhanced lift, allowed for slower maneuvering speeds, and helped prevent stalling. The VariViggen was powered by a pusher propeller at the back of the aircraft and had vertical fins at the wingtips called winglets, which improved the rate of climb and cruising speed. These two features also reoccurred in many of Rutan’s designs. Figure 1.2 shows some of Rutan’s earliest aircraft.

Rutan had begun construction of the VariViggen in his spare time while still working for the air force, and it took him four and a half years to complete it. With only seventy-five hours on the aircraft, Rutan flew the VariViggen to Oshkosh, Wisconsin, to give the public its first viewing during the 1972 Air Venture, the annual fly-in held by the Experimental Aircraft Association (EAA), which is the premiere aircraft organization for homebuilts and experimental aircraft. The crowd thrilled at the futuristic-looking aircraft.

“When you look at the wide variety of his designs from the VariViggen to SpaceShipOne and everything in between,” said Tom Poberezny, the President of EAA, “Burt has been a design leader. He’s always been creative and pushing the envelope.

“If you attend a forum at Oshkosh, it is always a packed house because people want to find out what’s the latest and greatest in Burt’s fertile mind. And that becomes motivational for people in terms of the excitement of being inside of design theory, design thinking, and innovation.”

Rutan gave the VariViggen the tail number N27VV. Characteristic of Rutan, the tail numbers of his aircraft weren’t arbitrary. All U. S. aircraft begin with N, but the “27” stood for the model number Rutan gave it, and VV obviously stood for VariViggen.

Another revolutionary aircraft made its debut at the 1972 AirVenture. The tiny little Rand Robinson KR-1—at a length of 12 feet 6 inches (3.8 meters), a wingspan of 17 feet 2 inches (5.2 meters), and a weight of 310 pounds (140 kilograms)—generated a lot of strange looks and disbelief. Ken Rand’s homebuilt aircraft had started people talking and thinking a little differently about the way airplanes were built. The outer wing panels, vertical and horizontal tail surfaces, and other parts of the aircraft were made using polystyrene—the same stuff foam coolers and coffee cups are made.

Even though plywood, which is technically a composite because it is made of wood layers glued together, was also used to build the fuse­lage, the KR-1 made use of composites like no other aircraft of its time. Polystyrene is very light, but it is also very weak. So, epoxy and cloth made of Dynel, a synthetic fiber, covered the polystyrene in order to give it the rigidity and strength needed to hold together. The KR-1 had a profound influence on the evolution of large-scale use of composite materials in homebuilt aircraft.

Rutan’s next design, the VariEze, also a pusher prop with a canard and winglets, took him only three and a half months to complete by taking the use of composites to a whole new level. “I didn’t have as a goal to build better, lighter, safer, more affordable composite structures. I saw it as a way that I could take a complex aerodynamic shape and build it quickly and get it into flight test,” Rutan said.

ґ

Fig. 1.2. The early aircraft designs and projects of the Rutan Aircraft Factory (RAF) came in many shapes and sizes, including Voyager, AMSOIL Racer, Quickie, Defiant, VariViggen, Grizzly, NGT, Long-EZ, AD-1, Catbird, VariEze, Boomerang, and Solitaire. Provided courtesy of Scaled Composites

V_________________________________________________________________________________________

“The KR-1 was a wooden airplane with Dynel and foam to shape its outer shape. Its primary structure was wood—the fuselage and wings and tail—whereas if you took the wood out of it, it would fall apart. The VariEze was different. Its composite was its primary structure.” The composite Rutan had used was polystyrene foam sandwiched between layers of fiberglass. “I started my composite work with moldless methods that I used on the VariEze and the Defiant and a bunch of our airplanes,” Rutan said. “I did that by copying what they did when they did repairs to molded European sailplanes. European sailplanes were made, and still are, in molds.”

But to fix damage to one of these sailplanes, it wasn’t necessary to go back to the mold. “The brainstorm that I had was, ‘Wait a minute, I could build a whole airplane with these repair methods.’ And that’s how I came up with hotwire wing cores and the hand-carved foam for the fuselage box. And sure enough, I built a whole airplane with­out a mold.” Figure 1.3 shows Rutan with a composite panel during the assembly process.

Rutan originally had no intention to sell the VariEze. He built it as a research aircraft to do more testing with the canard concept. But during its introduction to the public at EAA’s 1975 Air Venture, the public went wild for the design. Rutan responded by slightly enlarging the design and selling the VariEze as a kit airplane, so homebuilders could purchase plans and components to build it themselves.

“The VariViggen, the VariEze, all these designs, were unique in the fact that they were out of character from the type of design that was typical of the day,”Tom Poberezny said. “He breaks the mold every time he does something.” Figuratively speaking, of course.

In 1986, Rutan’s Voyager made the first nonstop flight around the world without refueling. It lifted off from Edwards Air Force Base with its tanks full of 7,011 pounds (3,181 kilograms) of fuel, circumnavigated the globe without once landing, covering a distance of 24,986 miles (42,212 kilometers), and then touched down nine days later at Edwards Air Force Base with 106 pounds (48 kilograms) of fuel to spare.

The amazing strength-to-weight ratio of the graphite fiber and honeycomb composite that Rutan used to build Voyager allowed a wingspan of 110 feet 8 inches (33.8 meters) and a primary structure weighing in at only 939 pounds (426 kilograms). Fuel actually accounted for 72 percent of its gross takeoff weight.

It was hard not to notice Rutan’s design and engineering prowess. And soon NASA, defense contractors, and large aircraft manufacturers began knocking at the door. In 1982, the year construction actually began on Voyager, Rutan founded Scaled Composites to specialize in proto­type development, offering design all the way through flight testing of full-scale vehicles or scaled-down versions and models. Figure 1.4 shows early designs that Scaled Composites worked on, including the

Starship, Pegasus, and the Pond Racer. Scaled Composites built some of these designs from start to finish, but for others the company only contributed to part of the construction.

“Things got more conventional,” explained Rutan. “I mean the way we build airplanes. They are still sandwich. They tend to be more honeycomb core than foam core. They tend to prepreg, and we cure them at higher temperatures. We still do them without the autoclave. And we occasionally come up with a breakthrough in manufacturing methods.”

But the manufacturing processes, while important, were never the driving force. As always, it was the design and the need to fly that drove the manufacturing processes. And after about thirty years from the time Rutan graduated college, he started to wonder what was next. Space was never that far from Rutan’s mind, or reach. In his bookshelf was a fat binder that contained original writings of Wernher von Braun. It was the Mars project. Rutan decided, “‘Damn it! Nobody else is going to do this. I’ll do something for space.’ That didn’t dawn on me until about ’93 that if I focused on suborbital, then I could do something interesting.”

Burt Rutan described the idea of the feather maneuver as the pivotal piece of the puzzle needed for the design of SpaceShipOne. Reentry into Earth’s atmosphere was the most critical point of every spaceflight. By deploying the feather mechanism, referred to as “carefree” and “hands – off,” the aerodynamic drag increased substantially, resulting in very low thermal loads. This was because the spaceship slowed down so quickly in the upper atmosphere that when it reached the thick atmosphere, it was traveling with much less energy. Because there was less energy, there was less heat being generated, and SpaceShipOne didn’t get as hot. On ascent after the boost, as SpaceShipOne continued to slow and close in on apogee, the test pilot put the feather up. “We put the feather up because we want to have as much time as possible to troubleshoot if it doesn’t
go up,” Melvill said. “It goes up with two different pneumatic actuators, either one of which can do the job. They are fed out of two separate high-pressure bottles. And you can put both bottles to one or the other. We had redundancy.”

Going up to space had its challenges, but coming back down was where a space program was truly tested. And the feather was SpaceShipOne’s ticket back home. Figure 3.15 shows SpaceShipOne with its feature in the extended position.

“So, we would put it up as soon as we were out of the atmosphere because if we put it up in the atmosphere, we would start doing loops.”

The rear half of each wing folds upward about a hinge line, looking like a jack-knife. It took less than 20 seconds for the feather to deploy to an angle of 65 degrees, and the pilot watched the instrument panel to make sure it went all the way up.

“As soon as you moved the handle, that unlocked it, and as soon as it was unlocked, you’d hear it,” Melvill said. “Without the motor running, it was very quiet. And you would hear it go konk in the back as it unlocked. As soon as we heard that, you would put the feather up with the handle. There were two handles right next to each other on the left side. The feather took a long time, and it made a noise going up. You could hear the air hissing into the large-diameter actuators.”

After SpaceShipOne reached apogee, going over the top, it began to pick up speed and continued to follow a ballistic arc downward much

ґ

Fig. 3.16. The feather extends and retracts by air-powered actuators, or pistons, that are attached on either side of the fuselage and connected to each side of the wing near their trailing edges. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

к__________________________ )

like the parabola traced by a ball thrown into the air and as it drops back down to the ground.

The spacecraft had a lift-to-drag ratio of about 0.7 in the feathered configuration, so the descent was nearly vertical, with an angle of attack of 60 degrees. While in space, a video camera mounted in SpaceShipOne’s tail boom captured the image of the feather shown in figure 3.16.

Now as SpaceShipOne transitioned from space to reentry, the atmosphere began to get thicker and thicker. Mach 3.25 was the fastest reached by SpaceShipOne. This corresponded to an airspeed below 160 knots equivalent airspeed.

“You come back a little faster than you go up,” Melvill said. “You get a tremendous amount of g-forces on your body when you are coming back. We were looking at 5.5 g’s on reentry.”

The pilot didn’t wear a g-suit. But he did experience a decelera­tion force above 5 g’s for around 10 seconds. Since the pilot sat upright the entire flight and SpaceShipOne reentered the atmosphere belly first, it was critical for the pilot to train beforehand in order to build up his g-tolerance.

“You see because of the rods and cones in your eyes,” Melvill explained. “They need oxygen-enriched blood to feed them. If the blood gets drained down to where there is not much oxygen – enriched blood behind your eyes, you go blind. You just black out. And you can still hear and think and move the stick. But you can’t see. And that would be hard to fly if you couldn’t see.”

In the feather configuration, SpaceShipOne acted like the conical­shaped shuttlecock, or birdie, used in the sport of badminton. Originally made of feathers and now more commonly made of plastic, the shuttle­cock’s skirt has such high drag compared to its base that after a hit from a racket, the shuttlecock automatically orients itself base-first in the direction of flight. The Scaled Composites team took advantage of the two important aspects of this concept when considering the reentry of SpaceShipOne. The high drag caused rapid deceleration, and the self-aligning tendency ensured the proper orientation.

“You don’t even need to do anything coming back down. It is a ‘carefree’ reentry,” Melvill said. “You could put your hands behind your head and take your feet off the rudder pedals and just wait. And you could reenter in any attitude. You could be tumbling when you reenter. You could be upside-down when you reenter. You could be knife-edge and the feather will turn you around and straighten you out. It happens real slowly.”

A terminal velocity of 60 knots equivalent airspeed is reached in this high-drag configuration. This corresponds to a ballistic coefficient,
calculated by using the weight, drag, and cross-section of SpaceShipOne, of 12 pounds per square foot (psf), compared to that of 60 psf for the early Mercury capsules. A low value of the ballistic coefficient means that the spacecraft will begin to slow down quickly in the thin atmosphere. So, SpaceShipOne experiences only low overall structural and thermal loading. It goes from supersonic to subsonic in about a minute and a half.

“The temperature when we reenter around the airplane is very high,” Melvill said. “It is about 1,200 degrees, but that’s the air temperature against the skin. Because that happens at 100,000 feet [30,480 meters] or more, there is so little air to conduct the heat into the structure. The molecules of air are so far apart because it is only 1 percent, or less, atmosphere up there. So, it takes time for that heat to be conducted into the structure, and we’re through that heating period before it has time to get into our airplane. Burt designed it that way, and that was very clever. He made sure that we wouldn’t spend very much time under the conditions where we could melt the airplane.”

During a presentation at the Experimental Aircraft Association’s 2006 AirVenture at Oshkosh, Wisconsin, Rutan described the differ­ence between the thermal protection system of SpaceShipOne and the Space Shuttle: “You don’t have the problems going Mach 4 that you do going Mach 25.

“On the boost, SpaceShipOne sees temperatures that are too hot for the skin at the nose and on the leading edges. That’s all. To be conser­vative, we protected some of the areas that got relatively hot on reentry. That’s why you see that stuff down under the nose and up underneath the wing. However, our measurements there showed that none of that was required. SpaceShipOne doesn’t need any thermal protection at all for reentry. It only needs several pounds of material for boost.”

In cooperation with the U. S. Air Force, SpaceShipOne reentered into restricted airspace controlled by Edwards Air Force Base. But within the restricted airspace, the Office of Commercial Space Transportation (AST) had designated a location, a box roughly 2.5 square miles (6.5 square kilometers) in size, for SpaceShipOne to come down through during reentry.

This was certainly a piloting challenge because in order to reenter through the box, the pilot already had to be in position on the way up. So not only did the pilot have to make sure the wings were level, the nose was pointed up, asymmetries were compensated for, and the occasional wind shear was counteracted, he had to try to position SpaceShipOne so that once the engine shut down and the atmosphere was gone, it would coast more than 100,000 feet (30,480 meters)

г >1

Fig. 3.17. SpaceShipOne returns from space as a glider and makes a horizontal landing similar to way the Space Shuttle does it. Although not the most efficient glider, SpaceShipOne had a glide range of around 60 miles (97 kilometers). Mojave Aerospace Ventures LLC, photograph by Scaled Composites

V_________________ ) feet to apogee, free fall back down, and then drop through a relatively small-sized box.

“Our priorities were we wanted to get altitude, and we wanted to leave the atmosphere without a lot of body rates or gyrations,” Binnie said.

The third goal was to come back inside the box. “But controlling the body rates and maneuvering the vehicle to find that box were kind of at odds with each other.”

SpaceShipOne continued to descend with its feather up. This configuration was so stable that in the atmosphere at the higher altitudes, it was easier for the pilot to just leave the feather up, even though SpaceShipOne had performed a safe reentry. However, there wasn’t much control. The pilot couldn’t pitch the nose and roll the wings, but he was able to change the direction that the nose pointed.

“This is something we didn’t feel necessary to test, but it is likely that you could survive a feather-up landing in SpaceShipOne,” Rutan said. “We did not plan to ride it down if the feather didn’t come down. We planned to jump out.”

At an altitude below 70,000 feet (21,340 meters), the feather was retracted and locked. SpaceShipOne, flying subsonically, transformed into a glider.

“I always had the space bug, keep in mind,” Rutan said. “When did I jump in and do it myself? It came in a time when I thought I could do it. And it wasn’t with SpaceShipOne at first. I was going to do a capsule, and launch it from an airplane that did a steep climb and a parachute recovery.” He began sketching out ideas in 1993.

“I was going to build something to fly out of the atmosphere. I’m not saying the things that I originally laid out were easy. They weren’t easy, but they weren’t really innovative. They were pretty straightforward. It didn’t require anything that was new or patentable or breakthrough in nature.”

His first ideas focused on a single-person rocket carried as an external store by a mothership. The carrier aircraft would pull up and then shoot it off like a missile.

“Around 1995 or so, we were designing and starting to build an aircraft called Proteus,” said Doug Shane, the vice president of business development and the first engineer that Rutan hired at Scaled Composites. An award-winning test pilot himself, Shane also became director of flight operations, which is a position he has held at Scaled Composites since 1989. Figure 1.5 shows Shane in Mission Control with Rutan at his side.

Proteus was a utility aircraft designed to fly at high altitudes above

60,0 feet (18,290 meters), but one of its design requirements was to launch a single-person suborbital rocket. Proteus would perform a zoom maneuver at 27,000 feet (8,230 meters), pulling up to 40 degrees to assist the rocket’s trajectory. Figure 1.6 shows the original launch concept with the rocket attached by an offset mounting, and figure 1.7 shows its separation from Proteus.

When Rutan got word of the formation of the X Prize, well before it was called the Ansari X Prize, he decided to change the design from a single-person capsule to a three-person capsule, which was a condition set forth by the X Prize. Figure 1.8 shows the rocket during ascent and the capsule and booster parachuting down after reentry.

The most important part of the design of the spacecraft was the feather, the little protuberances pointed upward away from the blunt end of the capsule. Acting and looking like the “feathers” of a

Ґ ^

Fig. 1.3. Burt Rutan began his pioneering work with composites on the VariEze, the second air­plane he designed and built. In 1975, the VariEze took him three and a half months to construct, whereas his first airplane, the VariViggen, took more than four and a half years. Mojave Aerospace Ventures LLC, photo­graph by Scaled Composites

к________ ) badminton shuttlecock, the design would accomplish two very important things. First, the high drag would decelerate the capsule very quickly, which would tremendously reduce the thermal loading and the dangers of heat buildup during reentry. And second, it would act to self-right and stabilize the capsule, orienting the capsule’s blunt side down no matter what the attitude during initial reentry. Rutan would call this his “carefree” reentry. This allowed the spacecraft to reenter at a near-vertical trajectory. The Space Shuttle, in comparison, had to precisely control its attitude during reentry, too shallow and it would skip off the atmosphere, too steep and it would experience catastrophic heating.

The capsule would then float down over the water. “I wanted to pick it out while it was still under the chute with a helicopter,” Rutan said.

The method was very similar to the way that film canisters ejected from the very first spy satellites were recovered during Project Corona, the joint effort between the Central Intelligence Agency (CIA) and U. S. Air Force. A film canister would parachute down, and an aircraft with a large catch would swoop by and snag it out of the sky.

“My baseline at first was that if it went into the water it was an unexpected failure or emergency. I wanted to grab them and helicopter them back to the launch site,” Rutan said.

Something about a parachute and helicopter blades make it seem like a bit of an odd combination, though, even for Rutan. “When you work with parachute recovery,” Rutan mused, “you take certain generic risks that you just can’t get around. And I thought I could do it. I think it was a much bigger decision that led me to develop something that could survive a steep reentry and land on a runway and not have to be controlled in attitude during reentry.

“That concept, that design, that approach was much more significant.”

So, the ideas of a capsule and a parachute were scrapped. But air launch was still on the table. Scaled Composites would also stick with

г л

Fig. 1.4. Scaled Composites built complete aircraft as well as components for many vehicles. Just a few of these are Pegasus,

Starship, Triumph, ATTT, ARES, and Pond Racer. Provided courtesy of Scaled Composites

V_____________________________ )

using the name “feather” even though the final design looked more like a pair of broken wings.

“If you can buy some time in the event of a propulsion problem instead of being this high off the ground when the motor quits or does something funny,” said Shane while sticking his hand out to his side about four feet off the ground, “if you are at 50,000 feet [15,240 meters], you really have a lot more time to deal with it. It gives you an awful lot more options.”

Early models, like those shown in figure 1.9 and figure 1.10, used a high-drag speed brake and large deflecting elevons as the feather mecha­nism for reentry. And Rutan’s team demonstrated several models where the feather worked subsonically. But when it came to supersonic speeds, like those encountered during reentry, they didn’t trim supersonically. In other words, they were uncontrollable. If the center of gravity (CG) was moved back, they would fly okay, but then they became unstable at sub­sonic speeds. A computerized fly-by-wire flight control system might have made them flyable, but the cost was too high and the reliability too low.

This was an enormous setback. Only two manned, winged vehi­cles had made it to space, the X-15 and the Space Shuttle. Both had fatal accidents during reentry. An X-15 had a flight-control failure in 1967, and the Space Shuttle Columbia had a failure of its thermal protection system in 2003. It was necessary to solve this problem before any more forward progress could be made.

“Finally, maybe it was some spicy food he ate late at night or some other kind of epiphany,” Shane said about Rutan. “He suddenly realized that maybe the thing to do would be to pivot part of the wing and the tails on a hinge on the body and provide that high-drag configuration. And that ended up satisfying all the subsonic and supersonic aerody­namic challenges. That was actually a pretty clever concept, and that’s what we went forward with.”

Figure 1.11 shows the new spacecraft design with the feather deployed for “carefree” reentry.

With the wings returned to the normal flight configuration, SpaceShipOne became a glider. The hard part was certainly over, and the pilot had time to take a breath and take in the view again. But his work was not completely over. Figure 3.17 shows SpaceShipOne gliding over the high desert of Mojave.

If SpaceShipOne was off course during the boost phase, it could be far away from where it needed to land. However, the spacecraft had a glide ratio of seven to one. So, SpaceShipOne had glide range of about 60 miles (97 kilometers) after it defeathered. “It’s got an awful lot of capability to deal with poor trajectory,” Doug Shane said.

The pilot also had to resolve a technical glitch with the global positioning system (GPS) receiver. It would drop out or lose its way during spaceflights. “The GPS receiver was never previously tested in that high and in that fast of a flight regime,” Pete Siebold said. “And so it had software difficulties of its own. The GPS receiver was some­thing you buy from a company off the shelf. It just didn’t perform the way it was supposed to.”

In one of the spaceflights, the GPS receiver reset by itself, but for the other two, the pilot had to reset it.

“So, we had to do a power cycle. The avionics go away while it is booting back up, and then it does a realignment of the inertial navi­gation system once it powers up again. But we could live with that fault. We had workarounds,” Siebold said.

The spaceship glided down for 10—15 minutes and was much lighter now that the oxidizer and fuel were burned off. SpaceShipOne was not able to land safely with a full load of oxygen and fuel. The extra weight changed the balance, and it was just too heavy for the landing gear to take. So, for an abort, it would have to dump all the nitrous oxide, but it still had to manage with the remaining mass of rubber.

Although SpaceShipOne did a good job gliding down and getting close to the airport, it did not have all the controls or responsiveness of a typical glider, so its maneuvering when it came to landing was limited. Early in the program, a few landing attempts were almost too short or too long for the runway.

Pete Siebold and Brian Binnie modified the landing technique, allowing SpaceShipOne to easily compensate for coming in too high or too low. “We would fly at 8,500 feet [2,590 meters] above sea level above our touchdown point,” Siebold said. “And we had a 360-degree turn to make back to that point again, and then we would be lined up for the final touchdown on the runway. The original technique allowed you to vary the radius of that turn. If you were too low, you could decrease the radius, and your circumference was your flight path. And if you were too low, you could make up for being low on energy by flying that tight radius. Or you could widen it out.

“We also had one last-ditch effort to make any adjustments, and that was to put the landing gear down. When the landing gear was up,

Ґ

Fig. 3.18. Landing proved to be a bigger challenge than anyone had anticipated. There was only one shot at it. SpaceShipOne had to come in at the right altitude and speed or it risked overshooting or undershooting the runway. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

V__________________________________________________

с л

Fig. 3.19. Once SpaceShipOne touched down, steering was very limited. The nose skid and the rear landing gear’s brakes brought the craft to a quick stop, but since it was unpowered, it needed some help to get off the runway. This photograph shows Sir Richard Branson, Paul Allen, and Burt Rutan (left to right) sitting on the tailgate with SpaceShipOne under tow. Dan Linehan

V J

it was a seven-to-one glide ratio. With the landing gear down, it was a four-to-one glide ratio. The problem was that once you put it down, you couldn’t put it back up. So, you had to be sure that you had sufficient elevation to make the runway.”

SpaceShipOne would spiral in for a landing while reaching key alti­tude points that were provided by the TONU. An energy predictor similar to what was used during boost showed the pilot where SpaceShipOne would be at the key altitudes based on the current turn and descent rates. The pilot would then adjust his speed and turn so that SpaceShipOne would end up at the place it needed to be.

“After we developed that and utilized it, we landed to within 500 feet [150 meters] of a given touchdown point on every subsequent flight. That was real rewarding,” Siebold said.

SpaceShipOne approached the runway at an airspeed of 140 knots indicated airspeed. But in order to put its gear down, it had to perform a special maneuver. “There were other peculiarities with the gear sys­tem,” Siebold explained. “You couldn’t put it out at your normal approach speed. So, the speed at which you flew the pattern was too fast to put the gear out and too fast to land. So, what you had to do was in your turn from base to final, you actually had to pull the nose up, slow the airplane down, put the gear out, dump the nose, with gear extension at 125 knots, and then speed back up to 140 knots.” Figure 3.18 shows SpaceShipOne gliding down to the runway at Mojave Airport.

The pilot had one last challenge to face. As it turned out, it was one that Charles Lindbergh faced seventy-seven years previously in

Ґ

Fig. 3.21. The North American X-15 was the only other manned, winged suborbital vehicle. SpaceShipOne shared some similarities with it, but trajectory was not one of them. The high-altitude and high-speed mission trajectories of the X-15 are shown in comparison to the SpaceShipOne trajectory. Mojave Aerospace Ventures LLC, provided courtesy of Scaled Composites

г

Fig. 3.20. The X-15 had enough fuel to power its rocket engine for about 2 minutes, so it required a B-52 to lift it to launch altitude. The X-15 flew from 1959 to 1968, posting a top speed of Mach 6.70, or 4,520 miles per hour (7,270 kilometers per hour), and a maximum altitude of 354,200 feet

(108,000 meters) on separate flights. NASA-Dryden Flight Research Center

v_____________________________________________

Table 3.2 SpaceShipOne’s and X-15 Suborbital Mission Comparison

Program goals

Number of vehicles in program Crew capacity

Number of rocket-powered flights

Combined time of rocket-powered flights (hours:minutes:seconds)

Number of flights above 100 kilometers (62.1 miles/328,000 feet)

1 st stage

Separation altitude Engine type Oxidizer and fuel Maximum engine burn time Trajectory for boost and reentry Maximum airspeed Maximum altitude Weightless time Reentry method Reentry max q Approach airspeed Touchdown airspeed Landing surface

Number of vehicles lost during flight testing Number of fatalities during flight testing

X-15

High speed and altitude 3 1

199*

30:13:49*

2

NASA B-52 carrier aircraft

45.0 feet (13,720 meters)

Liquid

Liquid oxygen and anhydrous ammonia 141 seconds (high-speed mission)

Approximately 40 degrees (high-altitude mission) Mach 6.70

354,200 feet (108,000 meters)

3.5 minutes

Pilot controlled pull-up

1.0 psf (550 KEAS)

270 KEAS

180 KEAS Lake bed 1 1

the Spirit of St. Louis, which had no front windshield. “The visibility out of SpaceShipOne is pretty restricted, and you got these really small windows, and there is no window in front,” Melvill said. “So, when you are lined up with the runway, you can’t see the runway. With a normal airplane, you can look out the front and see the runway.

“This one, the windows were on the sides, and as long as you were turning toward the runway, you could see it through the side win­dow. But as soon as you lined up with the centerline, you couldn’t see it anymore. The whole airport disappeared. So, that was a little bit
disconcerting I think for all of us. That’s why we had a chase plane sit­ting right on the wing calling out how high we were above the ground and basically keeping us straight as well.”

At 100 to 110 knots equivalent airspeed, the main landing gear at the rear hit first, and then the nose skid followed. There was no real way to steer once it touched down. The wooden tip of the nose skid brought it to a smooth, but slightly smoky, stop in front of an ecstatic crowd. Figure 3.19 shows SpaceShipOne being towed from the runway accompanied by Paul Allen, Burt Rutan, and Sir Richard Branson.