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Planetary News: Human Spaceflight (2007)Private Rocketship Falcon 1 Flies, Reaches Space, But Fails to Reach OrbitBy A.J.S. RaylMarch 20, 2007
After a year-long series of delays and last-minute aborts, Space Exploration Technologies (SpaceX) finally launched its Falcon 1 rocket at 1:10 pm local time on a demonstration test flight, but about three minutes into the flight, the mission control lost its charge, and the rocket failed to reach the intended orbit. The privately-funded, 70-foot long, 2-stage rocket, powered by liquid oxygen and kerosene, lifted off from Omelek island in the Kwajalein Atoll, a republic Marshall Islands, where SpaceX has launch facilities at 6:10 Pacific Daylight Time (9:10 Eastern Daylight Time / 0110 Greenwich Mean time). The first stage engine, which had experienced a shutdown on the launch pad earlier tonight, because of low chamber pressure readings, powered the rocket skyward for nearly three minutes. The spent stage then separated for a planned parachute-aided splashdown in the ocean for recovery. The second stage ignited and the rocket's nose cone jettisoned as the ascent continued. About two minutes into the second stage firing, the rocketship had reached an altitude of 161 kilometers (about 100 miles). One minute later, telemetry was lost, and the live webcast provided by the company stopped. The last bit of video seen from a camera mounted on the second stage showed, according to reports, what appeared to be some oscillations just before telemetry was lost. "We did have a roll-control anomaly," SpaceX CEO-CTO Elon Musk, a member of The Planetary Society's Board of Directors, told reporters minutes later. The rolling motion apparently caused the second stage engine to shut down early. The rocket did not reach the intended orbit, he said, and may have re-entered the atmosphere. Despite the problem, Musk called it "a very good day" for SpaceX. "I'll characterize this as a very good day for SpaceX," he said. "We successfully reached space and really retired almost all the risk associated with the rocket. So I feel very good about where things are." Today's mission, dubbed Demo-2, was primarily focused on gathering flight data. The rocketship also carried two experiments, the autonomous flight safety system and the low cost tracking and data relay satellite system transmitter. At this point, the fate of the Falcon 1 is not known for certain. The second stage was supposed to fire until almost T+plus 10 minutes to reach the planned orbit featuring a high point of 425 miles, a low point of 205 miles and inclination of 9 degrees north and south of the equator. "Regardless, we're thrilled here," Gwynne Shotwell, SpaceX vice president of business development, quickly announced from the company's Washington DC office. The Falcon clearly got to space with a successful liftoff, stage separation, second stage ignition and fairing separation, she said. What initiated the roll-control anomaly is not yet known and may not be known until a complete analysis can be done.
There has been much anticipation about the Falcon 1 launch, because it represents a new low-cost pathway to space. While the launch vehicles of today are little changed from those of 40 years ago and cost tens of millions of dollars to launch, the Falcon launch vehicle family is designed to provide breakthrough advances in reliability, cost, flight environment, and time to launch. The Falcon 1 is designed to carry up to 1,254 pounds into low orbit for $6.7 million. SpaceX first attempted to launch the Falcon 1 a year ago, also from Omelek island. That launch ended prematurely when the first stage engine shut down 34 seconds into flight due to a fire caused by a fuel leak seconds into liftoff. A U.S. Air Force Academy satellite was lost in the accident. An investigation board convened byU.S. Defense Advanced Research Projects Agency, the sponsor of the Falcon 1’s inaugural flight, conducted a thorough review and traced the malfunction to the failure of an aluminum B-nut at the turbo pump fuel inlet, believed to have been caused by stress corrosion, likely caused by prolonged environmental exposure at Kwajalein. Musk, who at first thought it might have involved a pad processing error but, called it "a stroke of unbelievably bad luck." The nut, he noted, " actually broke sometime in the 18 hours prior to launch." In any case, back at the ranch, SpaceX made a number of improvements to its overall launch system, reducing the total number of B-nuts in the engine assembly and replacing the rest with stainless-steel nuts. The company also implemented several updates to the vehicle, the ground-support equipment, and its overall launch processes and procedures, and scheduled the next launch for 4 pm yesterday.
Yesterday's launch was first delayed because they had some difficulty getting the telemetry stream from Omelek Island to the company's headquarters in El Segundo, California, where most of the operations team is overseeing the mission. The decision was made to suspend fueling in order to correct the data transmission problem. By 3:57 PM Paciifc, the data stream was working and engineers proceeded with the countdown, pushed to 4:45 pm Pacific (7:45 pm Eastern / 23:45 GMT). Less than two minutes before that scheduled lift-off, the ground control software triggered an automatic abort. "It commanded a switchover of range telemetry from landline to radio, which took place correctly, however, because of the hardware involved, this transition takes a few hundred milliseconds," Musk explained in an update on the SpaceX website. "Before it had time to complete, our system verification software examined state and aborted." The pre-launch simulations all passed, he explained, because the simulator did not account for a hardware driven delay in the transition. "We considered putting the vehicle into a safe state yesterday and updating the ground control software to make the very minor fix needed, but the safer course of action was to stand down," Musk said. So the launch was scrubbed for the day. The Falcon 1 launch team spent yesterday afternoon and evening (Kwaj time), updating the software to address the timing issue and verified there were no similar problems elsewhere. "We ran the software through several simulated countdowns and then once again with the rocket and range in the loop," Musk informed. Then they rescheduled the launch for 4 PM PDT today. At T-minus 3 minutes today, all systems remained "go" for Falcon 1's launch, and at 5:03 PM Pacific (8:03 pm EDT / 0003 GMT) T-minus 2 minutes, the liquid oxygen systems were configured for launch. But at 5:05 PM (8:05 pm EDT 0005 GMT) as the Merlin first stage main engine was igniting, the computers detected a problem causing computers to halt the countdown. The lift-off was aborted and the spacecraft went into safing mode. Within minutes, Shotwell told reporters the abort was tripped when computers detected the main engine chamber pressure was less than 0.1 percent lower than the redline limit. The low chamber pressure is believed to have been caused by the RP-1 kerosene's temperature, she announced later. But the launch of the Falcon was not scrubbed. Rather they recycled the countdown for a launch about an hour later and by 5:18 PM PDT (8:18 pm EDT / 0018 GMT ) the ground crew was partially offloading fuel and reloading the propellant for the second, partially successful launch attempt. "The things we were most concerned about were the first stage ignition and liftoff, the trajectory, the first stage because that goes through the most difficult portion of the atmosphere where you can have high winds and potentially go unstable or potentially have a structural problem and that went flawlessly," Musk told reporters after the launch. "We had zero anomalies whatsoever on the first stage." "Stage separation also went very well," Musk continued. "Separation events are the No. 2 killer of rockets after engine issues. Both the stage separation and fairing separation went flawlessly. Second stage ignition also was perfect, and we achieved steady state burn on the second stage. We did encounter late in the second stage burn a roll-control anomaly, which you may have seen on the video webcast. We feel that is something that's pretty straight forward to address. So all in all we feel pretty good about this launch."
SpaceX was founded in June 2002 by millionaire entrepreneur Musk, co-founder of PayPal, the world’s leading electronic payment system now owned by eBay. He created the venture "to help make humanity a space faring civilization" and pulled together a capable team of engineers hailing from the major aerospace corporations as well as smaller companies. The company, which currently boasts some 250 employees, is headquartered in El Segundo, California, where it houses its vehicle design and integration facilities. It conducts all engine and large-scale structural testing in McGregor, Texas. (Yes, they are currently hiring.) Although SpaceX is suffering the typical fits and starts most rocket manufactuers know well, the company already has an A-List of clients waiting for his rockets, including NASA, the Department of Defense, international commercial and government entities as well as private aerospace companies including Bigelow Aerospace and Space Development. The company was one of two winners of the NASA Commercial Orbital Transportation Services the competition, taking $278 million for three flight demonstrations of the Falcon 9 carrying the company's Dragon spaceship. Those demonstrations are slated to occur in late 2008 and 2009. The final flight will culminate in the transfer of cargo to the International Space Station (ISS) and return of cargo safely to Earth. Falcon 9 is capable of launching 10,350 kg (22,770 lbs) to low Earth orbit (LEO), and 4,550 kg (10,000 lbs) to Geosynchronous Transfer Orbit (GTO) in its medium configuration. The Falcon 9 Heavy will lift 28,400 kg (62,500 lbs) to LEO and 12,450 kg (27,400 lbs) to GTO. SpaceX's agreement with NASA also contains an option of similar value for three demonstration flights of the 7-person version of Dragon that will culminate with the transport of people to the ISS and back. How has SpaceX launched a low-cost rocket and government agencies have not? The cost of a rocket is primarily driven by five factors: overhead, propulsion, structures, avionics and launch operations. According to corporate data, SpaceX has "a flat management structure and singular product focus, resulting in lower overhead costs than other launch vehicle providers and a significant cost advantage for any given rocket design. With regard to propulsion, structures, and avionics, Falcon has the advantage of being a clean-sheet design focused purely on reliability and cost and the first rocket developed in the 21st Century to take advantage of the latest technologies. Through countdown automation and simplicity of design, the SpaceX rocket requires "an order of magnitude smaller launch crew than other US rockets." There is, however, "no single silver bullet breakthrough" responsible for the low costs, according to the corporate literature. SpaceX hopes to begin its commercial launches by the end of the year. "I feel extremely good about having successful satellite launches later this year," Musk said today after Falcon 1's launch, "especially when I know we've got two satellite launches lined up for later this year -- a Defense Department satellite and the other a Malaysian space agency satellite." |
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