SpaceX Falcon 1: Жеңіл ұшыру жүйесінің тарихы

Expendable launch system by SpaceX

Falcon 1 was a small lift launch vehicle that was operated from 2006 to 2009 by SpaceX, an American aerospace manufacturer. On 28 September 2008, Falcon 1 became the first privately developed fully liquid fueled launch vehicle to go into orbit around the Earth. The two stage to orbit rocket used LOX/RP 1 for both stages, the first powered by a single Merlin engine, and the second powered by a single Kestrel engine. The vehicle was launched a total of five times. After three failed launch attempts, Falcon 1 achieved orbit on its fourth attempt in September 2008 with a mass simulator as a payload. On 14 July 2009, Falcon 1 made its second successful flight, delivering the Malaysian RazakSAT satellite to orbit on SpaceX's first commercial launch (fifth and final launch overall). Following this flight, the Falcon 1 was retired and succeeded by Falcon 9. SpaceX had announced an enhanced variant, the Falcon 1e,
The only other orbital launch vehicles to be privately funded and developed were the Conestoga in 1982; and Pegasus, first launched in 1990, which uses a large aircraft as its launch platform. The total development cost of Falcon 1 was approximately US$90 million to US$100 million. While the development of Falcon 1 was privately funded, the first two Falcon 1 launches were purchased by the United States Department of Defense under a program that evaluates new US launch vehicles suitable for use by DARPA.

As part of a US$15 million contract, Falcon 1 was to carry the TacSat 1 in 2005. By late May 2005, SpaceX stated that Falcon 1 was ready to launch TacSat 1 from Vandenberg. But the Air Force did not want the launch of an untested rocket to occur until the final Titan IV flew from nearby SLC 4E. Subsequent and repeated delays due to Falcon 1 launch failures delayed TacSat 1's launch. After TacSat 2 was launched on an Orbital Sciences Minotaur I on 16 December 2006, the Department of Defense re evaluated the need for launching TacSat 1. In August 2007, the Department of Defense canceled the planned launch of TacSat 1 because all of the TacSat objectives had been met. An August 2005 update on SpaceX's website showed 6 launches planned for Falcon 1, with customers including MDA Corp (CASSIOPE, which eventually launched in 2013 on Falcon 9), Swedish Space Corp and US Air Force.

According to SpaceX, the Falcon 1 was designed to minimize price per launch for low Earth orbit satellites, increase reliability, and optimize flight environment and time to launch. It also was used to verify components and structural design concepts that would be reused in the Falcon 9. SpaceX started with the idea that the smallest useful orbital rocket was the minimum viable product (Falcon 1 with about to orbit), instead of building something larger and more complicated, and then running out of money and going bankrupt.

The first stage was made from friction stir welded 2219 aluminum alloy. It employs a common bulkhead between the LOX and RP 1 tanks, as well as flight pressure stabilization. It can be transported safely without pressurization (like the heavier Delta II isogrid design) but gains additional strength when pressurized for flight (like the Atlas II, which could not be transported unpressurized). The parachute system, built by Irvin Para­chute Corp­oration, uses a high speed drogue chute and a main chute. For the first two launches, the Falcon 1 used a Merlin 1A engine. An improved version of the Merlin 1A, the Merlin 1B, was supposed to fly on later flights of the Falcon 1, although it was further improved to create the Merlin 1C, which was first flown on the third Falcon 1 flight, and on the first 5 flights of the Falcon 9. The Falcon 1 first stage was powered by a single pump fed Merlin 1C engine burning RP 1 and liquid oxygen providing of sea level thrust and a specific impulse of 245 s (vacuum Isp 290 s). The pressure tanks are composite overwrapped pressure vessels made by Arde corporation with inconel alloy and are the same as those used in the Delta III. The second stage was powered by a pressure fed Kestrel engine with of vacuum thrust and a vacuum specific impulse of 330 s. The second stage was not designed to be reusable. In 2005 Falcon 1 was advertised as costing $5.9 million ($7.3 million when adjusted for inflation in 2015). In 2006 until 2007 the quoted price of the rocket when operational was $6.7 million. In late 2009 SpaceX announced new prices for the Falcon 1 and 1e at $7 million and $8.5 million respectively, with small discounts available for multi launch contracts, was projected to provide approximately for US$11 million. Several years ago, SpaceX was going to open up the smallsat launch market with the Falcon 1, which originally was to launch about 600 kilograms to LEO for $6 million; the payload capacity later declined to about as the price increased to around $9 million. Later, the Falcon 1e was to provide approximately for $11 million, but the company withdrew the vehicle from the market, citing limited demand.

All flights were launched from Kwajalein Atoll using the SpaceX launch facility on Omelek Island and range facilities of the Reagan Test Site. Vandenberg AFB Space Launch Complex 3W was the original launch site for Falcon 1, but it was abandoned at the test fire stage due to persistent schedule conflicts with adjacent launch pads. Cape Canaveral Air Force Station Space Launch Complex 40 (the Falcon 9 pad) was considered for Falcon 1 launches but never developed before Falcon 1 was retired.

Falcon 1 Versions Merlin A; 2006–2007 Merlin C; 2007–2009 Falcon 1e (proposed) Stage 1 1 × Merlin 1A 1 × Merlin 1C 1 × Merlin 1C Stage 2 1 × Kestrel 1 × Kestrel 1 × Kestrel Height(max; m) 21.3 22.25 26.83 Diameter 1.7 (5.57743 ft) 1.7 (5.57743 ft) 1.7 (5.57743 ft) Initial thrust(kN) 318 (71489.2 lbf) 343 (77109.5 lbf) 454 (102063 Takeoff weight(tonnes) 27.2 33.23 38.56 Fairing diameter(Inner; m) 1.5 1.5 1.71 Payload(LEO 185 km; kg) 420 470 (290 to polar) 1,010 (430 to polar) Price(Mil. USD) 6.7 7 10.9 minimal Price/kg(LEO 185 km; USD) ~14,000 ~14,000 ~8400 (~20,000 to polar) Success ratio(successful/total) 0/2 2/3 —

Launch sequence (maiden flight example);time scale is in seconds. The maiden flight of the Falcon 1 was postponed several times because of various technical issues with the new vehicle. Scheduling conflicts with a Titan IV launch at Vandenberg AFB also caused delays and resulted in the launch moving to the Reagan Test Site in the Kwajalein Atoll. The maiden launch was scheduled for 31 October 2005, but was held off, then rescheduled for 25 November, which also did not occur. Another attempt was made on 19 December 2005 but was scrubbed when a faulty valve caused a vacuum in the first stage fuel tank which sucked inward and caused structural damage. After replacing the first stage, Falcon 1 launched Saturday, 25 March 2006 at 09:30 local time. The DARPA payload was the United States Air Force Academy's FalconSAT–2, which would have measured space plasma phenomena. The launch took place on Saturday, 24 March 2006 at 22:30 UTC, from the SpaceX launch site on Omelek Island in the Marshall Islands. It ended in failure less than a minute into the flight because of a fuel line leak and subsequent fire. The vehicle had a noticeable rolling motion after liftoff, as shown on the launch video, rocking back and forth a bit, and then at T+26 seconds rapidly pitched over. Impact occurred at T+41 seconds onto a dead reef about 250 feet from the launch site. The FalconSAT–2 payload separated from the booster and landed on the island, with damage reports varying from slight to significant. SpaceX initially attributed the fire to an improperly tightened fuel line nut. A later review by DARPA found that the nut was properly tightened, since its locking wire was still in place, but had failed because of corrosion from saltwater spray. SpaceX implemented numerous changes to the rocket design and software to prevent this type of failure from recurring, including stainless steel to replace aluminum hardware (which is actually less expensive, although the trade off is being a little heavier in weight) and pre liftoff computer checks that increased by a factor of thirty.

The second test flight was originally scheduled for January 2007, but was delayed because of problems with the second stage. Before the January launch date, SpaceX had stated earlier potential launch dates, moving from September 2006 to November and December. In December the launch was rescheduled for 9 March, but delayed because of range availability issues caused by a Minuteman III test flight, which would re enter over Kwajelein. The launch attempt on 19 March was delayed 45 minutes from 23:00 GMT because of a data relay issue, and then scrubbed 1 minute 2 seconds before launch at 23:45 because of a computer issue, whereby the safety computer incorrectly detected a transmission failure caused by a hardware delay of a few milliseconds in the process. 20 March attempt was delayed 65 minutes from an originally planned time of 23:00 because of a problem with communications between one of the NASA experiments in the payload and the TDRS system. The first launch attempt on 21 March 2007 was aborted at 00:05 GMT at the last second before launch and after the engine had ignited. It was, however, decided that another launch should be made the same day. The rocket successfully left the launch pad at 01:10 GMT on 21 March 2007 with a DemoSat payload for DARPA and NASA. The rocket performed well during the first stage burn. However, during staging, the interstage fairing on the top of the first stage bumped the second stage engine bell. The bump occurred as the second stage nozzle exited the interstage, with the first stage rotating much faster than expected (a rotation rate of about 2.5°/s vs. expected rate of 0.5°/s maximum), thereby making contact with the niobium nozzle of the second stage. Elon Musk reported that the bump did not appear to have caused damage, and that the reason why they chose a niobium skirt instead of carbon–carbon was to prevent problematic damage in the event of such incidents. Shortly after second stage ignition, a stabilization ring detached from the engine bell as designed. At around T+4:20, a circular coning oscillation began, which increased in amplitude until video was lost. At T+5:01, the vehicle started to roll, and telemetry ended. According to Elon Musk, the second stage engine shut down at T+7:30 because of a roll control issue. Sloshing of propellant in the LOX tank increased oscillation. This oscillation would normally have been dampened by the Thrust Vector Control system in the second stage, but the bump to the second stage nozzle during separation caused an overcompensation in the correction. The status of the first stage is unknown; it was not recovered because of problems with a nonfunctioning GPS tracking device. The rocket reached a final altitude of and a final velocity of 5.1 km/s, compared to 7.5 km/s needed for orbit. SpaceX characterized the test flight as a success, having flight proven over 95% of Falcon 1's systems. Their primary objectives for this launch were to test responsive launch procedures and gather data.

Following the three prior failures, the SpaceX team assembled the fourth rocket using available parts in six weeks as a last chance for the company. A Boeing C 17 Globemaster III was chartered to quickly deliver the rocket, but along the way, the rocket partially imploded when depressurization exceeded what the SpaceX team had expected from the C 17's manual and the rocket had to undergo emergency repairs to be saved. Despite the challenges, the fourth flight of the Falcon 1 rocket successfully flew on 28 September 2008, delivering a 165 kilogram (363 pound) non functional boilerplate spacecraft into low Earth orbit. Liftoff occurred at 23:15 UTC on 28 September 15 minutes into a 5 hour launch window. If the launch had been scrubbed, it could have been conducted during the same window until 1 October. 9 minutes 31 seconds after launch, the second stage engine shut down, after the vehicle reached orbit. Following a coast period, the second stage restarted and performed a successful second burn, resulting in a final orbit of 621 × 643 km × 9.35°. The rocket followed the same trajectory as the previous flight, which failed to place the Trailblazer, NanoSail D, PRESat and Celestis Explorers spacecraft into orbit. No major changes were made to the rocket, other than increasing the time between first stage burnout and second stage separation. This minor change addressed the failure seen on the previous flight, recontact between the first and second stages, by dissipating residual thrust in the first stage engine before separating them. Ratsat and the attached second stage are still in orbit as of 2021.

SpaceX announced that it had completed construction of the fifth Falcon 1 rocket and was transporting the vehicle to the Kwajalein Atoll launch complex where it was to be launched on 21 April 2009, which would be 20 April 2009 in the United States. Less than a week before the scheduled launch date, Malaysian news reported that unsafe vibration levels had been detected in the rocket and repairs were expected to take about six weeks. On 20 April 2009, SpaceX announced in a press release that the launch had been postponed because of a potential compatibility issue between the RazakSAT spacecraft and the Falcon 1 launch vehicle. A concern had been identified regarding the potential impact of predicted vehicle environments on the satellite. On 1 June, SpaceX announced that the next launch window would open Monday, 13 July and extend through Tuesday, 14 July, with a daily window to open at 21:00 UTC (09:00 local time). The launch on Monday, 13 July was successful, placing RazakSAT into its initial parking orbit. Thirty eight minutes later, the rocket's second stage engine fired again to circularize the orbit. The payload was then successfully deployed. After the launch Elon Musk, founder and CEO of SpaceX, told a reporter the launch had been a success. "We nailed the orbit to well within target parameters pretty much a bullseye" Musk said.

Following the fifth flight, future launches of Falcon 1 were postponed, and eventually cancelled, and the vehicle decommissioned from service, with SpaceX stating "We could not make Falcon 1 work as a business."