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The Space Exploration Technologies Corporation (SpaceX) is a space-transportation startup company founded by Elon Musk. Its goal is to improve the cost and reliability of access to space by a factor of ten. It is developing partially reusable two-stage kerosene–liquid-oxygen launch vehicles. It was based in El Segundo, but moved to a former Northrop Grumman factory in Hawthorne, California, USA.
[edit] BackgroundSpaceX was founded in June 2002 by Musk, who is CEO and CTO. Musk co-founded startup companies Zip2 and PayPal and is chairman of Tesla Motors and SolarCity. As of March 2006 he had invested $100,000,000 of his money. In January 2005, SpaceX bought a 10% stake in Surrey Satellite Technology Ltd. There were 160 employees in November 2005,[1] and more than 500 by July 2008.[2] The launch crew in the Marshall Islands has 25 people, 6 in mission control. This small number, compared to companies with similar rockets, is part of cost reduction. Musk sees other space-launch services' high prices as supporting unnecessary bureaucracy. As of June 2008, the company's listed launch price costs are $7.9M and $9.1M per Falcon 1 and Falcon 1e launch.[3] Elon Musk stated after the failure of the third Falcon 1 flight attempt, "As a precautionary measure to guard against the possibility of flight 3 not reaching orbit, SpaceX recently accepted a significant investment. Combined with our existing cash reserves, that ensures we will have more than sufficient funding on hand to continue launching Falcon 1 and develop Falcon 9 and Dragon"; on August 4, SpaceX released further details; they had accepted a USD$20 million equity investment from the Founder's Fund.[4] [edit] Launcher versions
A Falcon 5 launcher was planned, but development was stopped. [edit] Launches[edit] Maiden test flight of Falcon 1
On November 26, 2005, the first launch attempt was scrubbed due to weather and ground holds. On December 19, 2005, a second scrub occurred when a faulty valve caused the first-stage kerosene tank to deform during an unfueling maneuver. The launch tower was redesigned to reduce liquid-oxygen boil-off and to avoid wind-related holds. On February 10, 2006, further static testing led to a delay. On March 17 and March 22 two static firings validated the rocket hardware and the launch procedures. The Falcon 1 maiden flight was scheduled for 21:00 UTC on 24 March 2006 (08:00 local time, 25 March). A ship to recover the first stage -- in a restricted down range zone -- caused a 90-minute launch hold. Launch was at 22:30 UTC (09:30 local time, 25 March), from Omelek Island, in the Kwajalein Atoll. After 29 seconds (T plus 00:00:29) the main engine failed, leading to vehicle loss soon after. Photography shows the engine on fire during ascent. An investigation by SpaceX and DARPA determined that corrosion on an aluminum nut led to a failure, resulting in a fuel leak. Corrective actions included replacing similar nuts with welding where possible, or with stainless steel nuts, otherwise.[11] There was a webcast of the flight from launchpad cameras, with mission-control voiceover, showing water-dump, ignition, and pad liftoff. The view switched to an onboard camera, with the atoll receding in the background. The webcast stopped 40 seconds into the flight. The 19.5-kilogram (43-pound) United States DARPA payload FalconSAT-2 was built by United States Air Force Academy cadets to investigate "space weather", or plasma in the upper atmosphere. The planned orbit was 450 kilometers (280 miles). [edit] Second test flight of Falcon 1The second Falcon 1 launched a demonstration payload to return data on the booster's performance, however it failed to reach orbit. The second stage was shut down a minute and a half before schedule (T+ 7:30) due to a control issue. [12] SpaceX later stated that "The second stage was otherwise functioning well and even deployed the satellite mass simulator ring at the end of flight! Actual final velocity was 5.1 km/s or 11,000 mph, whereas 7.5 km/s or 17,000 mph is needed for orbit." The first launch attempt was targeted for 2300 UTC, 20 March 2007 however it was aborted one minute and two seconds prior to launch (T minus 00:01:02) due to a ground control software handover failure. A second attempt was made at 00:05 UTC, 21 March 2007, but the launch was aborted automatically 0.5 seconds after firing the engines because the main engine chamber pressure was about 0.2 percent lower than allowable. The low pressure was caused by the fuel being colder than desired. The third attempt successfully launched the rocket at 01:10 UTC, 21 March 2007 (13:10 local time, 20 March 2007), the vehicle separated from the first stage booster and fairing at approximately 6:14 PST. The webcast from the vehicle was lost at T+ 5:05 at an altitude of approximately 300 kilometers, but SpaceX was able to retrieve telemetry for the entire mission. The video showed a coning motion that increased during the second stage burn, then a roll immediately before loss of signal.[13] Musk noted that the control problem was initiated during stage separation, when the shut down kick of the main engine exceeded their predictions. This caused a bump between the first stage and second stage engine nozzle, along with sloshing in the tanks. The vehicle's systems were designed to damp out sloshing, but the unexpected motion exceeded design parameters. [12] SpaceX stated they were happy with the launch as the rocket reached space and validated the riskiest and most difficult parts of the new design. Musk expressed confidence that they would solve the control issue and noted that all new rockets typically have these problems to work out; "I think they had something like 12 Atlas failures before the 13th one was success. To get this far on our second launch being an all-new rocket -- new main engine, new first stage, new second stage engine, new second stage, new fairing, new launch pad system, with so many new things -- to have gotten this far is great." [14] A post-mission report declared this launch "the end of the test phase for Falcon 1 and the beginning of the operational phase." [15] [edit] First operational flight attempt (third flight)The third Falcon 1 launch attempt took place on August 3, 2008 at 03:34 UTC[16] (15:34 local time) from Kwajalein.[17] The flight was carrying the Trailblazer (Jumpstart-1) satellite for the US Air Force Operationally Responsive Space Office,[16] two cubesats for NASA, PRESat and NanoSail-D,[16] mounted on an adapter being tested for ATSB of Malaysia,[18] and a Space Burial payload for Celestis.[19] The rocket did not reach orbit, according to first SpaceX statements because the second stage separation failed to take place.[17][16] A subsequent press release from SpaceX's Elon Musk announced that the stage separation took place and nominal thrust was achieved on Stage 2, but excess transient thrust from the new Merlin 1C engine was enough to cause Stage 1 to reconnect with Stage 2. This transient thrust was anticipated but not at the levels that were observed. The minimal thrust was not evident at sea level as the pressure present in the engine was at or below 10psi, below detectable levels in the 14psi ambient environment at Kwajalein. Elon Musk stated that, allowing for available launch times, launch 4 could take place as soon as September.[20] Musk also stated that aside from the transient thrust, everything else performed flawlessly. SpaceX was unable to test the slosh baffles meant to solve the problems with Flight 2 as the rocket never reached orbit. However Musk stated that he was confident their precautions would sufficiently solve the issue.[20] [edit] Upcoming launchesThe maiden launch of the Falcon 9 is scheduled for the fourth quarter of 2008 with a U.S. government payload, followed closely by the launch of a payload for the Canadian MDA Corporation.[21][dubious ]. On May 2, 2005, SpaceX announced that it had been awarded an Indefinite Delivery/Indefinite Quantity (IDIQ) contract for Responsive Small Spacelift (RSS) launch services by the United States Air Force, which could allow the Air Force to purchase up to $100,000,000 worth of launches from the company.[22] On April 22, 2008, NASA announced that it had awarded an IDIQ Launch Services contract to SpaceX for Falcon 1 and Falcon 9 launches. The contract will be worth between $20,000 and $1 billion, depending on the number of missions awarded. The contract may cover launch services through June 30, 2010, for launches through December 2012.[23] Elon Musk stated in the same April 22 announcement on the company's webpage that SpaceX has sold 14 contracts for flights on the various Falcon vehicles.[24] [edit] Future development[edit] Heavy lift launchersOn September 8, 2005, SpaceX announced the development of the Falcon 9 rocket, which will have nine Merlin engines in its first stage.[25][26] The design is an EELV-class vehicle, intended to compete with the Delta IV and the Atlas V rockets. Both stages will be designed to be reusable. A similarly designed Falcon 5 rocket was also envisioned to fit between the Falcon 1 and Falcon 9, but development was dropped to concentrate on the Falcon 9. The company purchased the McGregor, Texas testing facilities of defunct Beal Aerospace, where it is refitting the largest test stand at the facilities for Falcon 9 testing. The stand will test the 9 Merlin 1C engines of the Falcon 9, which will deliver 350-metric-tons-force (3.4-meganewtons) of thrust, well under the stand's capacity of 1,500 metric-tons-force (15 meganewtons). SpaceX plans to develop the Merlin 2 engine,[citation needed] a scale version of a larger F-1-class engine. The company is rumored to be working on a very large rocket to accompany the F-1-class engine, known by the codename "BFR" ("Big Falcon Rocket", originally "Big F'n Rocket"[citation needed]). [27] Musk said "Long-term plans call for development of a heavy lift product and even a super-heavy, if there is customer demand. We expect that each size increase would result in a meaningful decrease in cost per pound to orbit. For example, dollar cost per pound to orbit dropped from $4,000 to $1,300 ($8,800/kg to $2,900/kg) between Falcon 1 and Falcon 5. Ultimately, I believe $500 per pound ($1,100/kg) or less is very achievable." Musk said he expects to offer $1,000 per kilogram by 2010.[citation needed] [edit] Manned orbital spaceflight: SpaceX DragonSpaceX announced plans to pursue a manned commercial space program through the end of the decade.[28] On Friday 18 August 2006, NASA announced that the company was one of two selected to provide crew and cargo resupply demonstration contracts to the International Space Station (ISS) under the Commercial Orbital Transportation Services (COTS) program. SpaceX will demonstrate crew and cargo resupply using the SpaceX Dragon, a conventional blunt-cone ballistic capsule, which is capable of carrying 7 persons or a mixture of personnel and cargo to and from low Earth orbit.[29] It will be launched atop a Falcon 9 vehicle. The nosecone of the vehicle has a hinged cap, which opens to reveal a standard ISS Common Berthing Mechanism, which allows the Dragon to dock to the U.S. segment of the ISS. NASA's plan calls for SpaceX demonstration flights between 2008 and 2010. SpaceX may receive up to $278 million if it meets all NASA milestones.[30][31][32] [edit] External links Wikimedia Commons has media related to:
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