Falcon 1

Template:Short description Template:Use mdy dates Template:Infobox rocket Template:Private spaceflight Falcon 1 was a two-stage small-lift launch vehicle that was operated from 2006 to 2009<ref name="st20130301">Template:Cite news</ref> by SpaceX, an American aerospace manufacturer. On September 28, 2008, Falcon 1 became the first privately developed fully liquid-fueled launch vehicle to successfully reach orbit.<ref name="vance2015"> Template:Cite book</ref>Template:Rp<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The Falcon 1 used LOX/RP-1 for both stages, the first stage powered by a single pump-fed Merlin engine, and the second stage powered by SpaceX's pressure-fed Kestrel vacuum 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 July 14, 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).

While SpaceX had announced an enhanced variant, the Falcon 1e,<ref name="F1-retired"/> following this flight, the Falcon 1 was retired in favor of the Falcon 9 v1.0, the first version of the company’s successful and long-running Falcon 9 launch vehicle.

HistoryEdit

Private fundingEdit

The Falcon 1 rocket was developed with private funding.<ref name=usat20050617> Template:Cite news</ref><ref name=wired20070522> Template:Cite news</ref> 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The total development cost of Falcon 1 was approximately US$90 million<ref name=nasa20110427>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> to US$100 million.<ref>Template:Cite book</ref>

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.<ref name=wired20070522/><ref>Template:Cite news</ref><ref>Graham Warwick and Guy Norris, "Blue Sky Thinking: DARPA at 50," Aviation Week & Space Technology, Aug 18–25, 2008, p. 18.</ref>

Cancelled launchesEdit

As part of a US$15 million contract, Falcon 1 was to carry the TacSat-1<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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 December 16, 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<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

DesignEdit

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.<ref name="SpaceX Falcon1">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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 Template:Cvt to orbit), instead of building something larger and more complicated, and then running out of money and going bankrupt.<ref>Dead link: {{#invoke:citation/CS1|citation |CitationClass=web

}}Template:Cbignore Template:Dead Youtube links</ref>Template:Citation needed

File:SpaceX falcon in warehouse.jpg

First-stage view of the Merlin engine.

First stageEdit

The first stage was made from friction-stir-welded 2219 aluminum alloy.<ref name=ssc200708> Template:Cite journal</ref> 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 Template:Convert of sea-level thrust and a specific impulse of 245 s (vacuum I_sp 290 s).<ref name=ssc200708/> The first stage burns to depletion, taking around 169 seconds to do so.<ref name=ssc200708/>

Second stageEdit

The second stage Falcon 1 tanks were built with a cryogenic-compatible 2014 aluminum alloy,<ref name=ssc200708/> with the plan to move to aluminum-lithium alloy on the Falcon 1e.<ref name=ssc200708/> The helium pressurization system pumps propellant to the engine, supplies heated<ref name=ssc200708/> pressurized gas for the attitude control thrusters, and is used for zero-g propellant accumulation prior to engine restart. The Kestrel engine includes a titanium heat exchanger to pass waste heat to the helium, thereby greatly extending its work capacity.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The second stage was powered by a pressure-fed Kestrel engine with Template:Convert of vacuum thrust and a vacuum specific impulse of 330 s.<ref name=ssc200708/>

ReusabilityEdit

The first stage was originally planned to return by parachute to a water landing and be recovered for reuse, but this capability was never demonstrated.<ref name="Ruese">Template:Cite press release</ref><ref name="SFN-F4">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The second stage was not designed to be reusable.<ref name="Ruese" /><ref name="SFN-F4" />

Launch sequenceEdit

At launch, the first stage engine (Merlin) is ignited and throttled to full power while the launcher is restrained and all systems are verified by the flight computer. If the systems are operating correctly, the rocket is released and clears the tower in about seven seconds. The first-stage burn lasts about 2 minutes and 49 seconds. Stage separation is accomplished with explosive bolts and a pneumatically actuated pusher system.Template:Cn The second stage Kestrel engine burns for about six minutes, inserting the payload into a low Earth orbit. It is capable of multiple restarts.Template:Cn

PricingEdit

SpaceX quoted Falcon 1 launch prices as being the same for all customers.<ref name="falconpricing">SpaceX, Falcon 1 Overview: Pricing and Performance Template:Webarchive (website viewed August 31, 2010)</ref> In 2005 Falcon 1 was advertised as costing $5.9 million ($9.5 million when adjusted for inflation in 2025).<ref name="un20060101" /><ref>Template:Cite news</ref> In 2006 until 2007 the quoted price of the rocket when operational was $6.7 million.<ref>Template:Cite news</ref> 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,<ref name="SpaceX Falcon1" /> and in 2012 announced that payloads originally selected as flying on the Falcon 1 and 1e would fly as secondary payloads on the Falcon 9.<ref name="F1-retired"/>

Historically, the Falcon 1 was originally planned to launch about Template:Convert to low-Earth orbit for Template:Currency but later declined to approximately Template:Convert as the price increased to approximately Template:Currency. It was SpaceX's offering intended to open up the smallsat launch market to competition. The final version of the Falcon 1, the Falcon 1e,<ref>Jessy Xavier, "Europes First Vega Rocket Blasts Off Successfully Template:Webarchive," Oregon Herald, February 13, 2012</ref> was projected to provide approximately Template:Convert 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 Template:Cvt as the price increased to around $9 million. Later, the Falcon 1e was to provide approximately Template:Cvt for $11 million, but the company withdrew the vehicle from the market, citing limited demand.<ref name=nsj20120711> Template:Cite news</ref>

Launch sitesEdit

File:Falcon 1 Flight.jpg

Falcon 1 first flight attempt with NASA partnership cargo at Omelek Island launchpad

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.<ref> {{#invoke:citation/CS1|citation |CitationClass=web }} </ref> 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

VariantsEdit

Falcon 1 Versions<ref name="SpaceX Falcon1" /><ref>Template:Cite news</ref><ref>Template:Cite news</ref>	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 Template:Nowrap; kg)	420<ref>{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref>	470<ref>{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref> (290 to polar)	1,010<ref>{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref> (430 to polar)
Price (Mil. USD)	6.7	7	10.9
minimal Price/kg (LEO Template:Nowrap; USD)	~14,000	~14,000	~8400 (~20,000 to polar)
Success ratio (successful/total)	0/2	2/3	—

LaunchesEdit

Falcon 1 made five launches. The first three failed, however the subsequent two flights were successful, the first successful launch making it the first privately funded and developed liquid-propellant rocket to reach orbit.<ref name="vance2015" />Template:Rp The fifth launch was its first commercial flight, and placed RazakSAT into low Earth orbit.<ref name="F1success">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Launch attempts
Flight No.	Date / time (UTC)	Launch site	Payload	Payload mass	Orbit	Customers	Launch outcome	Launch video
1	March 24, 2006, 22:30	Omelek Island	FalconSAT-2	19.5 kg	LEO (Planned)	DARPA	Template:Failure	<ref group="video">Template:YouTube</ref>
1	Engine failure at T+33 seconds. Loss of vehicle.<ref name=junod20121115>{{#invoke:citation/CS1\|citation								CitationClass=web }}</ref> FalconSAT-2 landed on a storage shed near the launch site.<ref name="USAFA-.doc">{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref>
2	March 21, 2007, 01:10	Omelek Island	DemoSat		LEO (Planned)	DARPA	Template:Failure	<ref group="video">Template:YouTube</ref>
2	Successful first-stage burn and transition to second stage, maximal altitude 289 km. Harmonic oscillation at T+5 minutes. Premature engine shutdown at T+7 min 30 s. Failed to reach orbit.<ref name="demoflight_2_launch_update_12">Template:Cite news</ref>
3	citation	CitationClass=web }}</ref>	Omelek Island	Trailblazer PRESat NanoSail-D Explorers	4 kg	LEO (Planned)	ORS NASA NASA Celestis<ref name="launch_log">{{#invoke:citation/CS1\|citation	CitationClass=web }}</ref>	Template:Failure	<ref group="video">Template:YouTube</ref>
3	Residual stage-1 thrust led to collision between stage 1 and stage 2.<ref name="Mission3-Summary">{{#invoke:citation/CS1\|citation								CitationClass=web }}</ref>
4	citation	CitationClass=web }}</ref>	Omelek Island	RatSat	165 kg	LEO	SpaceX	Template:Success<ref name="SFN-F4" />	<ref group="video">Template:YouTube</ref>
4	Initially scheduled for Sep 23–25, carried dummy payload – mass simulator, 165 kg (originally intended to be RazakSAT).
5	July 14, 2009, 03:35<ref>Template:Cite press release</ref>	Omelek Island	RazakSAT	180 kg	LEO	ATSB	Template:Success<ref name=F1success />	<ref group="video">Template:YouTube</ref>
5	Only commercial contract launch of Falcon 1.

First flightEdit

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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 October 31, 2005,<ref name=nsf20051010>SpaceX reveals Falcon 1 Halloween date, NASASpaceFlight.com, October 10, 2005, accessed January 31, 2019.</ref> but was held off, then rescheduled for November 25,<ref name=nsf20051118>SPACEX set maiden flight – goals, NASASpaceFlight.com, November 18, 2005, accessed January 31, 2019.</ref> which also did not occur. Another attempt was made on December 19, 2005, but was scrubbed when a faulty valve caused a vacuum in the first stage fuel tank, causing the walls of the tank to sunk inward, resulting in structural damage. After replacing the first stage, Falcon 1 launched Saturday, March 25, 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, March 24, 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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 and pre-liftoff computer checks that increased by a factor of thirty.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>Template:Cite news</ref>

Second flightEdit

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 March 9, but delayed because of range availability issues caused by a Minuteman III test flight, which would re-enter over Kwajalein. The launch attempt on March 19 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. March 20 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 March 21, 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 March 21, 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.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref name="falconf2status">Template:Cite news</ref> 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.<ref name="falconf2status"/> The rocket continued to within one minute of its expected duration and also managed to deploy the satellite mass-simulator ring. While the webcast video ended prematurely, SpaceX was able to retrieve telemetry for the entire flight.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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 Template:Convert 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.<ref name="demoflight_2_launch_update_12"/> The SpaceX team planned both a diagnosis and solution vetted by third-party experts, believing that the slosh issue could be corrected by adding baffles to the second-stage LOX tank and adjusting the control logic. Furthermore, the Merlin shutdown transient was to be addressed by initiating shutdown at a much lower thrust level, albeit at some risk to engine reusability. The SpaceX team wished to work on the problem to avoid a recurrence as they changed over into the operational phase for Falcon 1.<ref name="Space28">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Third flightEdit

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} SpaceX attempted the third Falcon 1 launch on August 3, 2008 (GMT) from Kwajalein.<ref name=autogenerated1>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> This flight carried the Trailblazer (Jumpstart-1) satellite for the US Air Force,<ref name="launchwindow">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> the NanoSail-D and PREsat nanosatellites for NASA and a space burial payload for Celestis.<ref name="Celestis">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> The rocket did not reach orbit. However, the first stage, with the new Merlin 1C engine, performed perfectly.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}Template:Dead link</ref>

When preparing for launch, an earlier launch attempt was delayed by the unexpected slow loading of helium onto the Falcon 1; thus exposing the fuel and oxidizer to the cryogenic helium, rendering the vehicle in a premature launch state. Still within the specified window, the launch attempt was recycled, but aborted half a second before lift-off because of a sensor misreading. The problem was resolved, and the launch was again recycled. With 25 minutes left in the launch window, the Falcon 1 lifted off from Omelek Island at 03:35 UTC. During the launch, small vehicle roll oscillations were visible. Stage separation occurred as planned, but because residual fuel in the new Merlin 1C engine evaporated and provided transient thrust, the first stage recontacted the second stage, preventing successful completion of the mission.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The SpaceX flight-3 mission summary indicated that flight 4 would take place as planned and that the failure of flight 3 did not make any technological upgrades necessary. A longer time between first-stage engine shutdown and stage separation was declared to be enough.<ref name="Mission3-Summary" /> The full video of the third launch attempt was made public by SpaceX a few weeks after the launch.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Musk blamed himself for the failure of this launch, as well as the two prior attempts, explaining at the 2017 International Astronautical Congress that his role as chief engineer in the early Falcon 1 launches was not by choice and almost bankrupted the company before succeeding:<ref>Template:Citation</ref>

And the reason that I ended up being the chief engineer or chief designer, was not because I want to, it's because I couldn't hire anyone. Nobody good would join. So I ended up being that by default. And I messed up the first three launches. The first three launches failed. Fortunately the fourth launch which was – that was the last money that we had for Falcon 1 – the fourth launch worked, or that would have been it for SpaceX.

Musk further explained the situation to Ars Technica journalist Eric Berger:<ref>Template:Cite book</ref>

At the time I had to allocate a lot of capital to Tesla and SolarCity, so I was out of money. We had three failures under our belt. So it's pretty hard to go raise money. The recession is starting to hit. The Tesla financing round that we tried to raise that summer had failed. I got divorced. I didn't even have a house. My ex-wife had the house. So it was a shitty summer.

Fourth flightEdit

File:Spacex 067.jpg

The second-stage Kestrel engine glows red-hot during Falcon 1's fourth launch and first successful orbital flight.

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}} 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 repressurization exceeded what the SpaceX team had expected from the C-17's manual and the rocket had to undergo emergency repairs to be saved.<ref>Template:Cite book</ref> Despite the challenges, the fourth flight of the Falcon 1 rocket successfully flew on September 28, 2008, delivering a 165-kilogram (363-pound) non-functional boilerplate spacecraft into low Earth orbit.<ref name="SpaceX Falcon1 Flight4"/> It was Falcon 1's first successful launch and the first successful orbital launch of any privately funded and developed, fully liquid-propelled carrier rocket.<ref name=sfn20080928/>

The launch occurred from Omelek Island, part of the Kwajalein Atoll in the Marshall Islands.<ref name="MSC">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Liftoff occurred at 23:15 UTC on September 28, 15 minutes into a 5-hour launch window. If the launch had been scrubbed, it could have been conducted during the same window until October 1.<ref name="SpaceX updates">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 9 minutes 31 seconds after launch, the second-stage engine shut down, after the vehicle reached orbit.<ref name="MSC"/> The initial orbit was reported to be about 330 × 650 km.<ref name=sfn20080928> {{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref name="F3">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref name="SFN preview">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>Template:Cite news</ref>

Ratsat and the attached second stage are still in orbit as of 2021.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Fifth flightEdit

{{#invoke:Labelled list hatnote|labelledList|Main article|Main articles|Main page|Main pages}}

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 April 21, 2009, which would be April 20, 2009, in the United States.<ref name="MWN">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref>Template:Cite news</ref> On April 20, 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.<ref>Template:Cite news</ref> On June 1, SpaceX announced that the next launch window would open Monday, July 13 and extend through Tuesday, July 14, with a daily window to open at 21:00 UTC (09:00 local time<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>).

The launch on Monday, July 13 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.<ref name="falcon005">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> 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.<ref name="falcon005" />

The Falcon 1 upper stage is still in low Earth orbit as of 2024.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

End of ProgramEdit

Following the fifth flight, future launches of Falcon-1 were postponed, and eventually cancelled, and the vehicle decommissioned from service,<ref>Caleb Henry (August 10, 2016). "SpaceX's Shotwell: Falcon 1 Will not Return", Via Satellite. Retrieved February 10, 2022.</ref> with SpaceX stating "We could not make Falcon 1 work as a business."<ref name=Foust2016 /> Launches which had been booked onto Falcon-1 were moved to other vehicles or rebooked as Falcon-9 rideshare payloads.<ref name=Foust2016>Jeff Foust (August 9, 2016). "SpaceX offers large rockets for small satellites", Space News. Retrieved February 10, 2022.</ref>

ReferencesEdit

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