Category Space Ship One

Thirty-two days after Scaled Composites revealed its space program to the world, SpaceShipOne was about to take to the air for the first time. “Here we are about to embark on a flight test program with a spaceship,” said Doug Shane, the director of the flight test program. “And we started off with an unmanned captive-carry flight just to make sure the interactions between the two airplanes were fine.” The first test flights off the ground were captive carries, where White Knight and SpaceShipOne took off attached together in the mated configuration and did not separate during the flight. This was just like a giant wind tunnel, but instead of an enormous fan blowing air on SpaceShipOne, White Knight moved SpaceShipOne through the

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Fig. 7.2. SpaceShipOne took to the air for the first time on May 20, 2003, for an unmanned captive carry. A primary goal of the flight was to ensure that the two vehicles could safely fly while mated. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

air. Figure 7.2 shows SpaceShipOne and White Knight during the first captive carry.

With Pete Siebold at the controls and Brian Binnie in its backseat as flight engineer, White Knight carried the unmanned SpaceShipOne to an altitude of 48,000 feet (14,630 meters), which would eventually be the approximate launch altitude. They reached a speed of Mach 0.53 after the 700 feet per minute (210 meters per minute) climb to this altitude. Siebold and Binnie flew for 1.8 hours and found that White Knight had excellent handling qualities and could perform the captive carry without any stability, interference, or vibration problems. SpaceShipOne was now ready for a pilot.

SpaceShipOne Now Manned (2C)

Within specifically designated airspace, Mike Melvill rode inside SpaceShipOne during a 2.1-hour-long captive-carry test flight. Aside

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Flight Test Log Excerpt for 2C

Date: 29 July 2003

Flight Number Pilot/Flight Engineer

SpaceShipOne 2C Mike Melvill

White Knight 29C Brian Binnie/Cory Bird

Objective: First manned captive-carry flight of SpaceShipOne. A man-in-loop launch rehearsal and inflight checkout of all ship systems, including flight controls and propulsion system plumbing.

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Fig. 7.3. Two months after SpaceShipOne’s first test flight, Mike Melvill became the first test pilot to get behind the stick of SpaceShipOne. This mission was a captive carry, though. The Starship, designed by Burt Rutan, flew as a chase plane. Mojave Aerospace Ventures LLC, photograph by Scaled Composites

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Flight Test Log Excerpt for 3G

Date: 7 August 2003

Flight Number Pilot/Flight Engineer

SpaceShipOne 3G Mike Melvill

White Knight 30L Brian Binnie/Cory Bird

Objective: First glide flight of SpaceShipOne.

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

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from checking systems, Melvill preformed a full rehearsal for the first glide-test flight with Brian Binnie and Cory Bird, who crewed White Knight.

Figure 7.3 shows this test flight and the Starship chase plane trailing behind. Several chase planes flew alongside SpaceShipOne and White Knight at various stages during the flight test program. They monitored how SpaceShipOne performed from an external standpoint, and, should SpaceShipOne or White Knight run into difficulties, they provided a valuable extra set of eyes.

During this rehearsal, SpaceShipOne also practiced the communi­cation that would take place, which included sending data and video down to Mission Control on the ground.

Although pilots trained to fly SpaceShipOne with the simulator and White Knight, this was the first time that a pilot could actually feel the forces on the controls during flight. After Melvill exercised all the different systems aboard SpaceShipOne, which included parts of the feather and propulsion systems, SpaceShipOne was ready for the big next step.

As White Knight came in for a landing, though, Melvill couldn’t help trying to land, even though SpaceShipOne still remained fixed to White Knight. From the chase plane video, SpaceShipOne7s elevons moved as White Knight flared for landing. Afterward, Melvill joked with Binnie by congratulating him on such a fine landing.

“Ladies and gentlemen, we are at the start of the personal spaceflight revolution, right here, right now. It begins in Mojave, today. What is happening here in Mojave today is not about technology. It is about a willingness to take risk, to dream, and possibly to fail,” said Peter Diamandis during the morning of September 29, 2004, as XI, the name of the first required flight of SpaceShipOne in the quest for the Ansari X Prize, prepared to launch.

Mojave was abuzz. A little more than three months earlier, Mike Melvill had earned his astronaut wings as he piloted SpaceShipOne on a history-making flight just past the 100- kilometer (62.1 miles or 328,000 feet) line demarking the start of space. Now Rutan’s team set their sights on the most exciting and influential prize of the new millennium.

Pete Siebold, who had already flown two glide flights and one powered fight in SpaceShipOne, was selected to pilot the flight. Siebold had been training for three years for this moment, but a health scare forced a very disappointing change.

“There were two other guys that were more than qualified to fly that flight,” Siebold said. “At the time, I didn’t feel as though I was doing the team any justice by putting myself in that situation and flying
the mission when I probably wasn’t in the right frame of mind and not to mention healthy enough.” Siebold made the tough decision, but very fortunately his health issues were eventually determined to be nowhere near as serious as first suspected.

Rutan then turned to the test pilot with the most experience flying SpaceShipOne. Mike Melvill would get his chance to become an astronaut a second time, but to do so, he’d have to get back into training again. Figure 9.3 shows Melvill at the controls in the cockpit of SpaceShipOne preparing for XI.

Like Spirit of St. Louis, SpaceShipOne was stripped of anything absolutely nonessential. The lighter the craft, the greater the margin SpaceShipOne had for clearing the 100 kilometers (62.1 miles or 328,000 feet) because the removal of each and every pound enabled the spacecraft to go an additional 150 feet (46 meters) higher. SpaceShipOne needed all the help it could get. Melvill’s earlier spaceflight had cleared the 100 kilometers by only the slimmest of
margins, less than 500 feet (150 meters). And during this spaceflight, SpaceShipOne was not even carrying the full payload required by the rules of the Ansari X Prize.

Ironically, as the Scaled Composites team scrimped for a pound here and a pound there, removing a total of about 45 pounds (20 kilograms), they would have to add weight to simulate two passen­gers. “We had to carry 400 pounds [180 kilograms] in the back seat, which was a heck of a lot more load in that thing than we ever had before. And I had to be ballasted,” Melvill said.

Since Melvill weighed only 160 pounds (73 kilograms), he had to be ballasted up to 200 pounds (90 kilograms).These were the rules. But keeping the gross weight as low as possible was still critical. Every pound that didn’t have to be carried was a pound that the force from the rocket engine didn’t have to lift.

Figure 9.4 shows Melvill gesturing “okay” from a removable port as final preparations were made. SpaceShipOne was carried

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Fig. 9.4. Mike Melvill gives the thumbs up from the cockpit of SpaceShipOne as last-minute preparations are made. For the Ansari X Prize,

SpaceShipOne had to carry enough weight to simulate three 198-pound (90-kilogram) people. SpaceShipOne just barely made it past 328,000 feet (100,000 meters) without the extra weight, so it was necessary to bump up the performance of the rocket engine. Mojave Aerospace Ventures LLC, photograph by David M. Moore

into the air at 7:12 a. m. PST by White Knight with Brian Binnie behind the controls.

Separation occurred at 8:10 a. m. PST when flight engineer Matt Stinemetze, who sat in the back seat of White Knight, released SpaceShipOne from an altitude of 46,500 feet (14,170 meters). Clear of White Knight and no longer pushing forward on the control stick, Melvill fired the rocket engine, which had been enhanced to provide greater performance by increasing the amount of propellant and burn time.

“You could sure hear it,” Melvill said. “It was very loud—it was extremely loud.

“But it is a fabulous ride going up. I think that people who go on the next one—the passengers—will get the most exciting thing they ever did. A lot of noise. They are going really fast. The acceleration is dramatic. You are accelerating at a huge rate. You just watch the speed going up.”

The cockpit shook as Melvill pulled the nose up, making a very sharp turn toward the sky above. “The straighter you flew it, the

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Fig. 9.5. A video-capture image shot from a chase plane shows SpaceShipOne spiraling up during its boost. Melvill struggled to control the rolls but still allowed SpaceShipOne’s rocket engine to fire so he would be sure to pass the 328,000-foot (100,000-meter) mark. SpaceShipOne rolled twenty-nine times. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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higher it would go in the same amount of time,” he said. “We didn’t need to burn the motor for its full length that it was capable of burning because it went up there quite easily.”

During his previous flight, though, he had battled wind shear, rocket asymmetries, and pitch control failure. These had prevented him from flying a very straight trajectory. Melvill was more than determined to nail the trajectory on this flight.

As SpaceShipOne blasted through the upper atmosphere, Melvill had closed up the two donuts on theTONU display, which meant he was doing a great job flying the planned trajectory, and he monitored the energy altitude predictor, an instrument that predicted how high SpaceShipOne would go once the rocket engine was shut down.

“You may be at 160,000 feet [48,770 meters],” Melvill said, “and it will say, if you turn it off right now, you’ll go all the way to 328,000 feet [100,000 kilometers]. So, you watch that instrument. That’s the primary instrument to know when to turn it off. Initially, we did it with a timer, and we just said you’re going to run 55 seconds. And at the end of 55 seconds, we’d shut it off.”

But only 60 seconds after lighting the rocket engine, traveling at Mach 2.7, SpaceShipOne was in trouble. The crowd hushed as the contrail from SpaceShipOne switched from a nice, smooth line to a wild corkscrew in the sky. Things happened fast. But from the angle of the shot displayed on the jumbo screen, it was hard to tell what was actually happening. Figure 9.5 shows SpaceShipOne rolling out of control, viewed from the cockpit of a chase plane.

“When he started doing the rolls, I thought he was dead,” recalled Erik Lindbergh. “I thought that was it—the craft was going to break up and he was done.”

Thousands of people were gripped in silence.

“I didn’t think he was doing rolls. I thought he was tumbling at that point,” Lindbergh recalled.

SpaceShipOne rolled right uncontrollably at an initial rate of 190 degrees per second, spiraling up toward space.

“I had one of the walkie-talkies, and I could hear Melvill talking to ground control,” Ansari said. “He said that everything is fine. It didn’t look fine. But because he was convinced that everything was fine, I felt comfortable.”

The rocket engine kept burning while SpaceShipOne still spun its way up, reaching a maximum speed of Mach 2.92 (2,110 miles per hour or 3,400 kilometers per hour). Melvill still kept his eye on the energy altitude predictor. As he explained, “Unless you see 328,000 feet [100,000 meters] in that window, you are not going to win the X Prize. So, you don’t want to turn it off until you read at least that much or more. And so that was why I didn’t turn it off when we were doing all those rolls, because it didn’t say 328,000 feet [100,000 meters] yet. I went to turn it off thinking, wow, something was wrong here. And when I looked at the energy height predictor, it was not predicting that we would go high enough. So, I just left the motor running and just ignored the rolling.”

At a total burn time of 77 seconds, Melvill finally shut off the rocket engine. His altitude was 180,000 feet (54,860 meters) at that point and only about halfway through its ascent. But as Melvill got higher and higher, the air became too thin for him to counteract the rolls with either the subsonic or supersonic flight controls. SpaceShipOne left the atmosphere still rolling at 140 degrees per second.

Melvill was able to keep from being disoriented by focusing on the Tier One navigation unit and not glancing out the windows. He acti­vated the feather and then focused on nulling-out the rolls with the reaction control system. “I just pushed it on, turned on both systems, and just left it on until it stopped it,” Melvill said.

By the time SpaceShipOne stopped rolling, it had completed twenty – nine rolls. The vehicle now continued to coast to an apogee of 337,700 feet (102,900 meters), but now Melvill could enjoy the 3.5 minutes of weightlessness and the view while still having time to take a few photos out the window.

On reentry, SpaceShipOne hit a top speed of Mach 3.0. Still in the feathered configuration, it decelerated from supersonic to subsonic,

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Fig. 9.6. By using the reaction control system (RCS), Mike Melvill stopped the rolls. He reached an apogee of 337,700 feet (102,900 meters), which gave him about 10,000 feet (3,000 meters) to spare.

Now, coming down was the easy part. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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Fig. 9.7. SpaceShipOne’s second spaceflight was nearly over as it approached Mojave’s runway. But before Melvill had gotten close to the airport, he did some early celebrating by rolling SpaceShipOne once more to make it an even thirty. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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Fig. 9.9. On October 4, 1957, Sputnik became the first man-made object to orbit Earth. The Soviet Union had launched the beach ball­sized satellite, which circled the planet for three months. Sputnik put the space race between the United States and Soviet Union into overdrive. Decades later, on this day, SpaceShipOne was ready to finish a race of its own. NASA

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while it reached a peak g-force of 5.1 g’s at 105,000 feet (32,000 meters).

At 61,000 feet (18,590 meters), Melvill retracted the feather to begin his glide back to Mojave. As SpaceShipOne descended, the chase planes caught up and tucked in behind. Figure 9.6 shows the view of SpaceShipOne from the Alpha Jet.

During the 18-minute glide to Mojave, SpaceShipOne suddenly rolled completely around, surprising the chase planes. But this roll wasn’t uncommanded. Melvill performed a victory roll, rounding out his total rolls for the flight at thirty.

Figure 9.7 shows SpaceShipOne coming in for a landing as the crowds lining the runway cheered.

“It was fabulous—it really was—knowing that we at least were halfway there. We went plenty high. And coming back and all the excitement, everybody was just thrilled to death,” Melvill said.

Melvill’s flight exceeded the altitude requirement by nearly 10,000 feet (3,050 meters) and satisfied the other rules set by the Ansari X Prize. To fulfill the remaining conditions, SpaceShipOne had to repeat the spaceflight within two weeks. Standing on SpaceShipOne, Melvill celebrated successfully completing the XI, as shown in figure 9.8.

“We knew what we had to do. My task was to not damage the air­plane. I wasn’t going to go for any altitude records but just plenty of margin and burn the engine as little as possible and land the airplane as smooth as possible so we didn’t have to fix anything. We didn’t even change the tires. We refueled it, and it was ready to go. We could have gone the next day,” Melvill said.

All the flight control surfaces are on the tail booms, which are mounted to the wingtips and pivot with the aft wing sections when the feather is deployed. Each tail boom has a vertical stabilizer and horizontal stabilizer.

Upper and lower rudders are mounted at the back of each vertical stabilizer for yaw control. Pitch and roll is controlled by elevons that are attached to the trailing edges of the outward extending horizontal stabilizers. The fiberglass construction of the elevon skin gives radio transparency for antennas. For control during supersonic flight, the entire horizontal stabilizer on each tail boom pivots.

Minor modifications were made to the tail booms during flight testing. To resolve an aerodynamic problem, the distance from tip to root of the horizontal stabilizers was increased by 16 inches (41 centimeters). Also, a triangular strake was added in front of each horizontal stabilizer, and a flow fence was added midspan on each horizontal stabilizer.

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Fig. 4.15. Critical to the safe return from space, the feather had only two positions, all up or all down. Redundant pneumatic actuators raised and lowered the feather. While retracted, the feather was held in place by a redundant locking system. However, only the force from the pressurized

actuators was needed to keep the feather fully extended. Mojave Aerospace Ventures LLC, photograph by David M. Moore

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Fig. 4.16. During reentry and with the feather extended at an angle of about 65 degrees, SpaceShipOne descended nearly level on its belly. It did not drop straight down, though, but instead moved forward as it fell. The diagram shows the angle of attack at 60 degrees, which is a measure of the direction of motion with reference to the position of the wing.

James Linehan

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“What a great thing to be able to fly glide selections without worrying about the rocket propulsion system or any of the other elements. And by separating all these variables out, you can learn how to fly the air­plane and make sure all the subsonic stuff is going to work,” Doug Shane said. In theory and in practice, yes, but it was still unnerving from a test pilot’s point of view when it came down to a vehicle that had never been flown before.

“The first glide flight was probably the one that was my least favorite because we didn’t even know if it would fly,” Mike Melvill said. “If you think about a normal airplane with an engine, we don’t just go out and fly it. We go out and taxi it slowly. We figure out if the brakes work, whether the steering works, and then we go a little bit faster until we can finally lift it off a few inches and say, ‘Yeah, looks like its going to fly.’ And then we fly.

“For this one, we just hooked it on the bottom of White Knight, went to about 50,000 feet [15,240 meters], and dropped it off. So, we didn’t have a clue how it would fly or whether it would be good, bad, or indifferent. It wasn’t great. We had to modify it a little bit. But it was flyable, and I was able to bring it back. But that was the scariest flight, I think. We just didn’t have any knowledge other than Burt’s ‘That looks about right. ’ It had never been in a wind tunnel. There was no formal wind-tunnel testing of the airplane at all. And so we tested it in the real wind tunnel.”

White Knight flying at 105 knots, 12 miles (19 kilometers) east of Mojave, released SpaceShipOne at an altitude of 47,000 feet (14,330 meters).The spaceship and mothership separated cleanly. SpaceShipOne flew freely for the first time and was stable once disconnected.

Over the 19-minute flight time, Melvill evaluated the handling and performance. During that short time, the controls and avionics oper­ated as expected while he began to expand the flight envelope. At Mojave Airport on Runway 30, SpaceShipOne came in nice and easy to make its first landing.

The twenty-nine rolls not only caused great concern for safety, but now doubt and skepticism started to creep into the back of people’s minds. One or two rolls wouldn’t have been so dramatic, and would not have left such a vivid impression. But with twenty-nine, even the most inexperienced spectator could tell things weren’t going as planned. The public had not yet bought into the whole idea of personal space travel. There was a big difference between being enthusiastic and thinking something was cool and being willing to put your own butt in the seat strapped to a rocket engine. Some people would of course be willing to take any risk to get into space. But that certainly wouldn’t be the best way to jumpstart an industry in this day and age. Sometimes perception, unfortunately, weighs heavier than fact.

“We saw this rolling departure, and that was cause for concern,” Binnie said. “Not from a safety or structural standpoint but a concern of perception. Others thought, ‘Well, they are just loose cannons out there. They don’t understand what they are doing. They are certainly not ready for prime time or carrying the trusting public.’ And so the clock is ticking.

“We had planned this to where we could potentially pull off three flights in two weeks if need be. But we were all getting kind of tired. We really didn’t want to have a problem on our second attempt. Everybody on the team was well aware of what was at stake and what would all be necessary should it have to come to a third flight. And any number of things could put us there. It could be bad weather, an avionics hiccup, range issues, telemetry things, and issues totally unrelated to flying the vehicle could have scuttled that event and forced us into a third evolution.”

The fact was that after evaluating the data from X1, the team determined Melvill had done too good of a job at pointing SpaceShipOne straight up. In this orientation, SpaceShipOne had no aerodynamic lift to correct unwanted motion. “You’ve got to be careful that you don’t go over on your back,” Melvill said. “It is real easy to pull so hard that you end up overturning.”

With the nose of SpaceShipOne pointed straight up, a degree or two off one way or the other was not much of a change in angle. But it turned out to be a tremendous change in terms of SpaceShipOne’s stability. So, when Melvill went beyond 90 degrees, he naturally tried to bring the nose back on track. This caused the angle of attack, the direction SpaceShipOne was pointing in relation to the direction of actual motion, to go to zero.

“The wing wasn’t lifting anymore, there was zero lift on the wing, then it departed,” Melvill explained. “It did a snap roll. And that was caused by the design of the airplane. The airplane was designed with a high wing and swept leading edge. Had that been a low wing, it would not have done what it did. We learned that lesson. On the next flight, we didn’t change the airplane at all. We just changed the pull – up schedule.”

The new plan for the trajectory was a more gradual pull-up during boost while making sure never to go to vertical. “And as

long as that wing is lifting, it won’t stall like that. But when it gets to zero lift, then you get separation on it, and the slightest little perturbation of airplane will cause it to roll or do something odd,” Melvill said.

None of the flights previous to XI had flown at high Mach numbers while at a zero angle of attack. Essentially, SpaceShipOne lost directional stability, so there was no way Melvill could counteract the weak thrust asymmetry, a wandering thrust line, coming from the rocket engine at the time. SpaceShipOne was still rocketing up, so by the time the first few rolls occurred, the atmosphere had disappeared. Aerodynamic forces were not longer causing the rolls, but since there was no air pressure to resist the rolling motion, once SpaceShipOne started to roll, it just kept going and going.

The structural loading on SpaceShipOne from the rolling was very low. Melvill’s safety was never in jeopardy, only his breakfast, which thanks to all of the unusual-attitude training in the Extra 300 aerobat­ic plane, remained in place. The very next day, Scaled Composites not only figured out what caused the rolling departure but also deter­mined a way to keep it from happening again.

As with the first rocket-powered launch of SpaceShipOne, Rutan wanted to fly on a significant day in aviation history. The anniversary of the first man-made object to orbit Earth was approaching. Russia’s Sputnik, as shown in figure 9.9, was launched on October 4, 1957, and circled Earth about 1,400 times at a peak apogee of 588 miles (947 kilometers). This milestone of spaceflight sent the space programs of the United States and the USSR into warp speed.

“We had three days to finesse this in the simulator,” Binnie said. “Between Mike’s flight and the final flight, it was Friday, Saturday, Sunday. It looked promising, but it was still only our sixth powered flight in the vehicle. There was no guarantee that we really under­stood it or that there weren’t some other gremlins that were going to leap out and get us.”

Mechanically, the most complicated system on SpaceShipOne was its feathering system. It was also the most important system on board for ensuring the safety of the pilot and the success of the mission. Rutan already had experience with movable-winged aircraft. His RAF analyzed the designs and loads for NASA’s scissor-wing AD-1 (refer to figure 4.13).

Before SpaceShipOne reentered the atmosphere, the aft section of both wings, including the tail booms, rose up as if the spacecraft were almost folding in half. With the feather extended, SpaceShipOne could reenter the atmosphere with very little pilot input required. This “carefree” reentry was one of the most important elements of Scaled Composites’ entire space program.

The feather is a separate structure from the forward wing sections and has its own spars and ribs. However, the aft wing sections and the tail booms do not move independently. Figure 4.14 shows the spar that runs through the fuselage from one end of the movable wing to the other, tying the feather all together.

Left and right pneumatic actuators, which are just cylinders with movable pistons, used air power to pivot the feather up or down along the hinge. The lower ends of each actuator are attached to the fuselage, and the upper ends are attached to the inner face of the aft wing section, as shown in figure 4.15.

There are just two positions of the feather, up or down. The angle the feather makes with the fuselage is preset to 65 degrees, so the pilot did not have to make any adjustments. It took about 13—14 seconds to raise or lower. The feather could be elevated on ascent once the airspeed was less then 10 knots equivalent airspeed. Figure 4.16 shows the 60-degree angle of attack for SpaceShipOne descending in the feather condition.

When the feather got to the fully extended position, there was no lock. It was just the force from the actuators that held the feather up. “As it turns out, it takes no load to put it up because you are weightless,” Rutan said. “When you are weightless, there are no aerodynamics. It takes no force. In fact, if you would unlock it in space, you could take a little cable and pull it right up. There is no load on it. Okay. But, you need to hold it up for reentry.” The reentry force on the flight test actually tried to push the feather down.

If the feather were to move or become disengaged at the wrong time, the results could be disastrous. To keep the feather in the retracted position and to keep it from moving during the other phases of flight, two I-shaped clasps from the locking system secure the trailing edges of the aft wing sections. To unlock the feather so it could be deployed, separate pneumatic actuators were pressurized to retract the clasps.

The design had built-in redundancy for the components that make up the feather system. The two clasps were coupled so they moved together. But they had separate pneumatic sources, lines, regulators, valves, and again, separate actuators. “So, I could have a fire. I could have a line come off. I could have a loss of pressure. I could have all of these things go wrong, and it doesn’t affect the other,” Rutan said.

The two different pressure sources could run either actuator. The redundancy of the locking system was identical to the redundancy of the elevating systems. They were two independent systems that, under normal conditions, acted in unison. However, either system could engage or disengage the clasps of the other system. Once SpaceShipOne was flying subsonically after reentry and the loading drops below 1.2 g, the pilot could retract the feather.

The fourth flight of SpaceShipOne was scheduled to be a glide flight. Figure 7.4 shows preparations being made the day before the flight. Melvill had successfully opened more than 60 percent of the subsonic flight envelope on the previous flight. This included speeds from stall to 150 knots. Now it was planned to open up the envelope even further.

The flight envelope indicated all the ways SpaceShipOne could safely fly, which included variations and combinations of speed, altitude, attitude, and other factors. The crews flew the easiest stuff, as the pilots and engineers gained confidence and began to nail down the flying characteristics. Step by step, they pushed the boundaries as they flew the vehicle more aggressively to reveal its limitations.

However, twenty minutes prior to separation, the launch had to be aborted due to a GPS malfunction with the avionics system. Figure 7.5 shows the mated pair during the aborted test flight prior to landing. Initially designated as 4G and 31L for SpaceShipOne and White Knight, respectively, the flight numbers were modified to 4GC and 31LC as a result of the abort. But it was possible to complete some systems testing prior to landing.

Flight Test Log Excerpt for 4GC

Date: 27 August 2003

Flight Number Pilot/Flight Engineer

SpaceShipOne 4GC Mike Melvill

White Knight 31LC Brian Binnie/Cory Bird

Objective: Second glide flight of SpaceShipOne. Flying qualities and performance in the spaceship feather mode. Pilot workload and situational awareness while transitioning and handling qualities assessment when reconfigured. As a glider, deep stall investigation both at high and low altitude and envelope expansion out to 200 knots and 4 g’s. Lateral directional characteristics including adverse yaw, roll rate effectiveness and control, including aileron roll and full rudder sideslips.

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Fig. 7.4. SpaceShipOne and White Knight are poised before the fourth test flight. Planned as SpaceShipOne’s second glide flight, the flight had to be aborted midair. Mojave Aerospace Ventures LLC, photograph by David M. Moore

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Fig. 7.5. It was necessary to abort the fourth test flight because of an avionics malfunction involving the global positioning system (GPS) prior to separation. However, before returning to Mojave, test pilot Mike Melvill completed some systems testing. Mojave Aerospace Ventures LLC, photograph by David M. Moore

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On this day, the 47th anniversary of Sputnik, Brian Binnie was selected to pilot SpaceShipOne for the second of the two flights required to win the Ansari X Prize. Melvill, who had been a backbone of the program, had paved the way for Binnie only five days earlier. Melvill would now be there flying White Knight along with Matt Stinemetze as flight engineer.

Gone.

Flight Test Log Excerpt for 17P

Date: 4 October 2004

Flight Number Pilot/Flight Engineer

SpaceShipOne 17P Brian Binnie

White Knight 66L Mike Melvill/Matt Stinemetze

Objective: Second X Prize flight: again ballasted for 3 place and 100 kilometer goal (328,000 ft). (We also really wanted to break the X-15 354 kft [thousand feet] record.)

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

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“He dropped me, and I dropped him,” Melvill said. “That was fun.”

White Knight and SpaceShipOne lifted off together at 6:49 a. m. PST on October 4, 2004, in the chill of the desert morning with the Sun rising. In an article Binnie wrote for Air <$_ Space, he echoed the thoughts of Melvill, “The program to develop and test Burt Rutan’s SpaceShipOne (SSI) had many different demands, but I can safely say the one that made the pilots uniformly uncomfortable was the hour – long wait in SSI while the White Knight carrier aircraft dragged it up to release altitude. During this time, there is little to do and the mind is somewhat free to wander.”

As the world watched, the pressure on Binnie was enormous. With the prize of $10 million on the line, Branson waiting down below poised to begin work on SpaceShipTwo, and the fact that it was ten months since the last time he flew SpaceShipOne, which resulted in a crash landing, Binnie had plenty to wrestle with inside his head. “For me personally, a problem or failure or inability to pull this off for whatever reason, the other side of that coin was a bottomless pit. It felt to me like an abyss.”

Tensions ran high on the ground, too. “I knew that if there would be any glitches, people would say that this is not ready for prime time,” Ansari said. “And it’s not ready for commercialization and all these things.”

But when it came time to launch, every trace of doubt or uncer­tainty disappeared with the first flash of the rocket engine. Binnie’s years of navy flying and skills as test pilot took control. At 7:49 a. m., an hour after takeoff, and 47,100 feet (14,360 meters), Stinemetze pulled the lever to drop SpaceShipOne.

Table 9.1 gives the transcript of the communication between Binnie and Mission Control from the moments before separation to when the feather was locked down after reentry.

“We had no reason to delay,” Binnie said. “So, as soon as I was separated, I armed and fired the rocket motor.”

Ignition occurred immediately, and off Binnie went. SpaceShipOne zoomed past White Knight close enough for Melvill and Stinemetze to hear the hybrid rocket engine, a spaceman’s version of buzzing the tower. Figure 9.10 shows SpaceShipOne beginning to make its turn toward space. After 10—12 seconds, Binnie was thinking, “Okay, I’m still alive. I’m still in the loop. I’m still managing this thing.” But as SpaceShipOne transitioned into supersonic flight, he relaxed. The hardest part was over.

“We wanted to get to the X Prize altitude and a secondary goal of trying to beat the X-15 record,” Binnie said. “So, we wanted lots of altitude. But we also wanted to exit the atmosphere without any rolls or gyrations or large body rates so that we didn’t scare off Branson and the whole SpaceShipTwo efforts. There was that dual-edge sword of precision flying on one side and performance on the other.

“We wanted to get the nose up to 60 to 70 degrees as quickly as we could, initially, a very aggressive turn,” Binnie continued. “Once we got there, we started slowing down the pitch rate on the vehicle so that we went from 60 degrees to about 80 to 82 degrees over the next 50 seconds or so. The bulk of the flight was just milking the nose between those pitch attitudes. And then the last 20 to 25 seconds was the start of a pull again to get to about 87 to 88 degrees nose up.”

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Fig. 9.10. Brian Binnie faced the toughest flight of his entire life on October 4, 2004. He hadn’t flown SpaceShipOne since the crash landing. Now he was behind the controls of SpaceShipOne while the world’s eyes watched his every move. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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The exhaust from SpaceShipOne s rocket engine streaking upward as the contrail from White Knight veers off to the left can be seen in figure 9.11.

Binnie continued, “The initial pitch attitude to 60 to 65 degrees meant you were going to take advantage of all that rocket motor energy that is available to you and convert that to altitude. And the pull-in endgame meant you were keeping angle of attack on the vehicle and making it less susceptible to rocket-motor asymmetry in the thin upper atmosphere, where you have a delicate balance between controlling those asymmetries with little aerodynamic control power to resist it.”

After 84 seconds, Binnie shut down the rocket engine when SpaceShipOne had reached 213,000 feet (64,920 meters), zipping upward as fast as Mach 3.09 (2,186 miles per hour or 3,518 kilometers per hour). Like a pot of gold at the end of a rainbow, $10 million waited at the other end of the ballistic arc.

“I went scooting right through the X Prize altitude and past the X -15 old record by 13,000 feet [3,960 meters] or so. I got to the point after rocket motor shutdown and the feather coming up, and I hadn’t touched any of the reaction control system yet to control body rates. The vehicle was just absolutely stable. I actually used reaction control to give myself a different view so I could take some pictures.”

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Fig. 9.11. The contrail of SpaceShipOne streaks spaceward as the contrail of White Knight peels off to the left. Brian Binnie fired the rocket engine for 84 seconds, shutting it down at 213,000 feet (64,920 meters). Dan Linehan

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Fig. 9.12. Well past the boundary of space, Brian Binnie had entered the black sky. SpaceShipOne coasted to an apogee of 367,500 feet (112,000 meters), surpassing the X-15 altitude record of 354,200 feet (108,000 meters). Mojave Aerospace Ventures LLC, photograph by Scaled Composites

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Binnie reached an apogee of 367,500 feet (112,000 meters), which exceeded the Ansari X Prize requirements by nearly 7.5 miles (12 kilometers), and experienced weightlessness for more than 3.5 minutes. Binnie had a little time to take pictures, and figure 9.12 shows one of his photographs. In addition to taking photos, as figure 9.13 shows, he had the chance to do some zero-g testing on a miniature SpaceShipOne. Binnie did not release M&Ms in space as did Melvill, and it’s still unconfirmed whether Binnie ate his allotment during the captive-carry phase. Doug Shane would not speculate on the origin of several faint crackling sounds heard over the Mission Control radio.

Although weightless at apogee, SpaceShipOne had not truly escaped Earth’s pull. SpaceShipOne started to freefall and began to
accelerate, reaching Mach 3.25, which was the fastest speed it had ever reached on any of the flights. As SpaceShipOne descended into the thick atmosphere, air friction now decelerated it, and at 105,000 feet (32,000 meters), Binnie faced a peak force of 5.4 g’s pushing against his body.

As the g-forces subsided and SpaceShipOne slowed down below the speed of sound, Binnie retracted the feather at an altitude of 51,000 feet (15,540 meters). The video frames, at two-second intervals, in figure 9.14 show the transition of the feather mechanism from the extended position to the retracted position. After reentry into Earth’s atmosphere, the feather had done its job. The pair of pneumatic actuators, which can be seen connecting either side of the fuselage to the trailing edge of the

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Fig. 9.13. Brian Binnie’s trajectory was spot-on during the ascent. The hard part was over, now that gravity had taken over control of the trajectory. Binnie had 3.5 minutes of weightlessness to savor. He snapped photos and sailed a SpaceShipOne model back and forth across the cockpit. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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wings, pulled downward. This caused the feather to retract, making SpaceShipOne streamlined once more and readying it for the glide back to Mojave.

SpaceShipOne, now configured as a glider, drifted homeward. Figure 9.15 shows Sir Richard Branson, Paul Allen, and Burt Rutan spotting SpaceShipOne in the sky above Mojave.

The world watched SpaceShipOne gliding down for 18 minutes.

“I don’t know,” Ansari said, “maybe naively, I just felt that there was no more danger and everything would be fine or if there were any glitches or problems, they would be very much manageable. I wasn’t too worried because I had watched landings of SpaceShipOne a few times before.”

After only 24 minutes from being dropped by White Knight, SpaceShipOne’s wheels hit the runway for a perfect landing, as shown in figure 9.16.

“Oh, it was absolutely wonderful,” said the 434th human to reach space, summing up his spaceflight.

Once the nose skid brought SpaceShipOne to a stop and the door popped open, Binnie was instantly welcomed back by his wife as Rutan, Allen, and Branson congratulated him on the victorious flight. Towed by a pickup truck, SpaceShipOne paraded up and down the flightline in front of the thousands and thousands of cheering supporters as Binnie stood triumphantly atop, as shown in figure 9.17.

“The whole experience was very emotional for me,” Ansari said. “Even though I had nothing to do with the design and the hard work that the engineers and the team had put into building SpaceShipOne, I just felt like part of the team. I was just so proud and happy that they were successful, and that was the greatest joy to see that happen.”

Eight years after it was announced, the Ansari X Prize was finally captured, just like the Orteig Prize, first offered in 1919 and claimed in 1927. The difference was that aviation would not just take a giant leap into the air but would leap past where the air was thin to the beginning of space.

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Fig. 9.14. As SpaceShipOne fell back to Earth, the feather eased it into the atmosphere. At 51,000 feet (15,540 meters), Binnie retracted the feather, as shown by the sequence given at two-second intervals. Mojave Aerospace Ventures LLC, video captures provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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Fig. 9.15. Sir Richard Branson, Burt Rutan, and Paul Allen (left to right), search the sky and spot SpaceShipOne as it nears the end of its 24-minute journey up and down from space. X PRIZE Foundation

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Fig. 9.16. Brian Binnie finished his flawless performance by making a perfect landing. After about a year and a half of flight testing, seventeen flights altogether, SpaceShipOne touched down on the runway for the last time. Mojave Aerospace Ventures LLC, video capture provided courtesy of Discovery Channel and Vulcan Productions, Inc.

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Fig. 9.17. In a matter of days, not weeks, SpaceShipOne made two spaceflights. No other vehicle in the history of space travel had accomplished this feat. Brian Binnie’s performance not only restored his confidence in himself but made it clear to the world that the future of space travel was happening right here, right now. X PRIZE Foundation

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Fig. 9.18. SpaceShipOne had done it. Eight years after its announcement by Peter Diamandis and the X Prize Foundation,

Brian Binnie had captured the Ansari X Prize. Burt Rutan, Paul Allen, and the rest of their team had pulled off the seemingly impossible.

Now was the time to celebrate the historic accomplishment and also to revel in the wonderment as the door to space flung wide open.

X PRIZE Foundation

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Table 9.1 Transcript of SpaceShipOne’s Ansari X Prize-Winning Spaceflight

This transcript was prepared using video filmed during the second Ansari X Prize spaceflight attempt from inside the cockpits of SpaceShipOne and White Knight and from inside Mission Control. The spaceflight was called X2 because it was the second attempt required by the Ansari X Prize and also called 17P because this rocket-powered flight was the seventeenth time SpaceShipOne flew. White Knight lifted off with SpaceShipOne from Mojave’s Runway 30 at 6:49 a. m. PST on October 4, 2004. The entire spaceflight lasted 1.6 hours (wheels up to wheels down for White Knight). The time stamps are hours:minutes:seconds a. m., PST. The transcript runs from just before SpaceShipOne is dropped from White Knight to just past feather retraction and lock after reentry. Acronyms used are:

AFFTC: Air Force Flight Test Center at Edwards Air Force Base

AST: Federal Aviation Administration Office of Commercial Space Transportation

BB: Brian Binnie in SpaceShipOne

BR: Burt Rutan in Mission Control

DS: Doug Shane in Mission Control

MC: Staff in Mission Control

MM: Mike Melvill in White Knight

MS: Marc de van der Schueren in the Alpha Jet chase plane

SS1: SpaceShipOne

SpaceShipOne’s journey had not ended with the Ansari X Prize, although the mission and the destination had substantially changed. SpaceShipOne was about to embark on two of its longest flights ever, one across the United States and one across the Solar System. Tyson V. Rininger

After a glide test, a rocket-powered flight, or a trip to space, SpaceShipOne made a horizontal landing on a runway like most other aircraft. As SpaceShipOne got ready to land, the pilot pneumatically actuated the nose skid and rear landing gear, as shown in figure 4.17.

A spring and gravity extended the nose skid into position. It had a maple wood tip that helped slow down the aircraft during landing. This unusual piece of landing gear also acted as a crush damper. Its simple design dramatically reduced the weight and complexity that is typical of retractable nose wheels.

The rear landing gear was also spring and gravity driven but had independent hydraulic brakes for each wheel. By fully depressing a rudder pedal, the brake engaged for the wheel on the corresponding side.

The aircraft was not equipped to retract the landing gear on its own. So, once the pilot put the landing gear down, the only way to get it back up was to land and let the ground crew reset it. There was a big, removable panel on SpaceShipOne’s belly where the rear landing gear is located that also provided access for ground support.

After resolving the avionics malfunction that caused the aborted glide flight, SpaceShipOne and White Knight were back up flying again the very same day. Melvill was dropped at 48,200 feet (14,690 meters) from White Knight flying at a speed of 105 knots. For his first maneuver, he put SpaceShipOne into a full stall to investigate stall characteristics.

The second maneuver was one of the most critical firsts of the entire flight test program. Evaluation of the feather would begin on this flight. The purpose of the feather was to decelerate SpaceShipOne during reentry into the atmosphere.

“That’s something you do in glide tests,” Burt Rutan said. “You don’t have to do that in spaceflight because once you decelerate from your spaceflight, you find yourself in a stable glide, which is identical to the way we flew the airplane on its first glide flight. So, we went out early in the program and put the feather up and put it down.”

Rutan had planned to do a high-speed pull-up in a glide flight and put the feather up as it peaked to simulate zero-g during the beginning of the program. But this turned out unnecessary and would have used up too much altitude. “We started off at 43,000 feet [13,110 meters] and put the feather up to make sure it flew the way we wanted,” Doug Shane said. “We ended up doing feather

Flight Test Log Excerpt for 5G

Date: 27 August 2003

Flight Number Pilot/Flight Engineer

SpaceShipOne 5G Mike Melvill

White Knight 32L Brian Binnie/Cory Bird

Objective: Same objectives as the aborted flight 31LC/4GC earlier today. Second glide flight of SpaceShipOne. Flying qualities and performance in the spaceship reentry or "feather" mode. Pilot workload and situational awareness while transitioning and handling qualities assessment when reconfigured. As a glider, stall investigation both at high and low altitude and envelope expansion out to 200 knots and 4 g’s. More aggressive, lateral directional characteristics including adverse yaw, roll rate effectiveness and control, including 360 degrees aileron roll, and full rudder side slips.

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

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deployments from tail-slide entries, and it just worked great. Everything was as good as we could have possibly hoped for.”

SpaceShipOne was gliding along at an airspeed of 90 knots when Melvill unlocked and activated the feather. As the tail booms began to elevate to their fully extended position of 65 degrees, the nose of SpaceShipOne pitched up but settled back to a near-level pitch. Melvill encountered a lot of buzzing and buffeting during the 70-second feathered descent.

With the feather deployed, SpaceShipOne dropped at a rate greater than 10,000 feet per minute [3,050 meters per minute]. However, it was extremely stable as it fell to the ground belly first.

“You could change the heading,” Mike Melvill said. “If you were pointing at Cal City, you could turn around and point it to Mojave. And you used the elevons to do that. It was kind of weird because normally it would roll, but your sensation was that it was yawing.”

“If you stepped on the rudders, it wasn’t perceptible to you what was happening. Nothing happened. The only thing that really did anything was lateral spin. It was kind of neat to go over and look at a different view, and look over there and see what was over there. We did that a lot when we were flying as a glider in the atmosphere.”

At 30,000 feet (9,140 meters) Melvill retracted and locked down the feather. SpaceShipOne was back as a glider, as shown in figure 7.6. He expanded the flight envelope for airspeed and g-force. And before landing, he executed SpaceShipOne’s first roll.