Misplaced Pages

#755244

121-549: The injector at the heart of Merlin is of the pintle type that was first used in the Apollo Lunar Module landing engine ( LMDE ). Propellants are fed by a single-shaft, dual- impeller turbopump . The turbopump also provides high-pressure fluid for the hydraulic actuators , which then recycles into the low-pressure inlet. This eliminates the need for a separate hydraulic drive system and means that thrust vectoring control failure by running out of hydraulic fluid

242-486: A Falcon 9 experienced an early engine shutdown on ascent. The shutdown occurred 2 minutes 22 seconds into the flight and was accompanied with an "event" seen on camera. The rest of the Falcon ;9 engines burned longer and did deliver the payload to orbit. However, the first stage was not successfully recovered. In a subsequent investigation SpaceX found that isopropyl alcohol , used as cleaning fluid,

363-546: A crewed spacecraft during the Apollo Program in the Lunar Excursion Module 's Descent Propulsion System , however, it was not until October 1972 that the design was made public. and U.S. patent 3,699,772 was granted to its inventor Gerard W. Elverum Jr. A pintle injector is a type of coaxial injector. It consists of two concentric tubes and a central protrusion. Propellant A (usually

484-655: 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). While SpaceX had announced an enhanced variant, the Falcon 1e , 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. The Falcon 1 rocket

605-504: A U.S. hydrocarbon rocket engine. The increase is due to the greater expansion ratio afforded by operating in vacuum, now 165:1 using an updated nozzle extension. The engine can throttle down to 39% of its maximum thrust, or 360 kN (81,000 lbf). Transporter-7 mission launch debuted a new Merlin Vacuum engine (MVac for short) nozzle extension design or variant aimed at increasing cadence and reducing costs. This new nozzle extension

726-534: 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

847-632: A damaged heat-shielding cover. The mission was a success, but the booster could not be recovered. A vacuum version of the Merlin 1D engine was developed for the Falcon ;9 v1.1 and the Falcon Heavy second stage. As of 2020, the thrust of the Merlin ;1D Vacuum is 220,500 lbf (981 kN) with a specific impulse of 348 seconds, the highest specific impulse ever for

968-548: 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 Kwajalein. The launch attempt on 19 March

1089-443: 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. 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

1210-401: A fuel, and was stated as having a sea-level thrust of 6,700 kilonewtons (1,500,000 lbf). Since the initial announcement of Raptor, Musk has updated the specification to approximately 230 tonnes-force (2,300 kN; 510,000 lbf)—about one-third the original published figure—based on the results of optimizing for thrust-to-weight ratio. Pintle injector The pintle injector

1331-424: A fully expendable mission. SpaceX also noted that unlike the previous Full Thrust iteration of the Falcon 9 vehicle, the increase in performance is solely due to upgraded engines, and no other significant changes to the vehicle are publicly planned. In May 2018, ahead of the first flight of Falcon 9 Block 5 , SpaceX announced that the 845 kN (190,000 lbf) goal had been achieved. The Merlin 1D

SECTION 10

#1732779895756

1452-399: 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

1573-406: A more evenly distributed combustion across the chamber section and more even heating. This has to be contemplated when designing the cooling system, or it might cause burn-through. The pintle injector is known to have caused throat-erosion problems in the early ablatively cooled Merlin engines due to uneven mixing causing hot streaks in the flow, however, as of 2021, it is not clear whether this

1694-479: A normal consistency like that of smooth peanut butter . Gelled propellants typically use either aluminum powder or carbon powder to increase the energy density of the liquid fuel base (typically MMH ) and they use additives to rheologically match the oxidizer (typically IRFNA based) to the fuel. For gelled propellants to be used on a rocket, face shutoff is mandatory to prevent dry-out of the base liquid during off times between pulses, which would otherwise result in

1815-449: A pintle injector tends to create a self-stabilizing flow pattern. Therefore, pintle-based engines are specially suitable for applications that require deep, fast, and safe throttling, such as landers . Pintle injectors began as early laboratory experimental apparatuses, used by Caltech 's Jet Propulsion Laboratory in the mid-1950s, to study the mixing and combustion reaction times of hypergolic liquid propellants. The pintle injector

1936-754: A pintle injector was considered for simplicity and lower cost on the Sea Dragon . In parallel with those projects, TRW continued development of other pintle engines, including by 1966 the URSA ( Universal Rocket for Space Applications ) series. These were bipropellant engines offered at fixed thrusts of 25, 100, or 200 lbf, (111, 445, or 890 N) with options for either ablative or radiatively cooled combustion chambers. These engines were capable of pulsing at 35 Hz , with pulse widths as small as .02 seconds, but also had design steady state firing life in excess of 10,000 seconds (with radiatively-cooled chambers). In 1967

2057-488: A rocket engine that would be "several times as powerful as the Merlin 1 series of engines, and won't use Merlin's RP-1 fuel". They indicated that the large engine was intended for a new SpaceX rocket, using multiple of these large engines could notionally launch payload masses of the order of 150 to 200 tonnes (170 to 220 short tons ) to low-Earth orbit . The forthcoming engine currently under development by SpaceX has been named " Raptor ". Raptor will use liquid methane as

2178-405: A small amount of the total flow trimmed out by a " servo-motor-controlled butterfly valve " to provide fine control of the mixture ratio. On November 24, 2013, Elon Musk stated that the engine was actually operating at 85% of its potential, and they anticipated to be able to increase the sea-level thrust to about 730 kN (165,000 lbf) and a thrust-to-weight ratio of 180. This version of

2299-592: A very compact, 8,200 lbf N 2 O 4 / MMH engine employing this feature was developed as a pitch and yaw thruster for the army's SENTRY missile program. This engine could throttle over a 19:1 thrust range and deliver repeatable "on" pulses as small as 8 milliseconds at any thrust level. A further refinement of the face shutoff injector was used on the Army Strategic Defense Command's Exoatmospheric Reentry-vehicle Interceptor Subsystem (ERIS). In its 900 lbf lateral divert engines

2420-652: Is a Merlin 1B model with only slight alterations. It was fired with a full mission duty firing of 170 seconds in November 2007, first flew on a mission in August 2008, powered the "first privately-developed liquid-fueled rocket to successfully reach orbit", Falcon 1 Flight 4 , in September 2008, and powered the Falcon 9 on its maiden flight in June 2010. As configured for use on Falcon 1 vehicles,

2541-539: Is a problem that applies to all pintle-based engines, or this was a design problem of the Merlin. Pintle injectors work very well with liquid propellants and can be made to work with gelled propellants, but for gas–liquid or gas–gas applications, conventional injectors remain superior in performance. The pintle injector is desirable for engines that have to be throttled or restarted repeatedly, but it does not deliver optimal efficiency for fuel and oxidizer mixing at any given throttle rate. In 1957, Gerard W. Elverum Jr.

SECTION 20

#1732779895756

2662-504: Is a type of propellant injector for a bipropellant rocket engine . Like any other injector, its purpose is to ensure appropriate flow rate and intermixing of the propellants as they are forcibly injected under high pressure into the combustion chamber , so that an efficient and controlled combustion process can happen. A pintle-based rocket engine can have a greater throttling range than one based on regular injectors, and will very rarely present acoustic combustion instabilities, because

2783-478: Is not possible. The initial version, the Merlin 1A , used an inexpensive, expendable, ablatively cooled carbon-fiber-reinforced polymer composite nozzle and produced 340 kN (76,000 lbf) of thrust. The Merlin 1A flew only twice: first on March 24, 2006, when it caught fire and failed due to a fuel leak shortly after launch, and the second time on March 21, 2007, when it performed successfully. Both times

2904-588: Is not reacted immediately as it passes through the oxidizer stream is projected onto the combustion chamber walls and cools them through evaporation, thus providing fuel film cooling to the combustion chamber walls, without incurring the mass penalty of a dedicated coolant subsystem. While pintle injectors have been developed for applications in rocket propulsion, due to their relative simplicity, they could easily be adapted for industrial fluid handling processes requiring high flowrate and thorough mixing. A given injector's performance can be easily optimized by varying

3025-522: Is now close to the sea-level thrust of the retired Rocketdyne H-1 / RS-27 engines used on Saturn I , Saturn IB , and Delta II . On 23 February 2024, one of the nine Merlin engines powering that launch flew its 22nd mission, which was at the time the flight leading engine. It is already the most flown rocket engine to date, surpassing Space Shuttle Main Engine no. 2019's record of 19 flights. The March 18, 2020, launch of Starlink satellites on board

3146-509: Is powered by a fuel-rich open-cycle gas generator similar to that used in the Apollo-era Rocketdyne F-1 engine. As of August 2011, SpaceX was producing Merlin engines at the rate of eight per month, planning eventually to raise production to about 33 engines per month (or 400 per year). By September 2013, SpaceX total manufacturing space had increased to nearly 93,000 square meters (1 million square feet), and

3267-696: Is shorter and, as a result, decreases both performance and material usage. This nozzle is only used on lower-performance missions, as with this nozzle, the MVac engine produces 10% less thrust in space. The nozzle decreases the amount of material needed by 75%; this means that SpaceX can launch over three times as many missions with the same amount of rare niobium metal as with the longer design. On July 11, 2024, Falcon 9 flight 354 launching Starlink group 9-3 from Vandenberg AFB in California experienced an anomaly with its MVac during an engine relight attempt to raise

3388-630: The F-1 engines used on the Saturn V . Conceived to be potentially used on more capable variants of the Falcon 9 Heavy, Markusic indicated that the Merlin 2 "could be qualified in three years for $ 1 billion". By mid-August, SpaceX CEO Elon Musk clarified that while the Merlin 2 engine architecture was a key element of any effort SpaceX would make toward their objective of "super-heavy lift" launch vehicles—and that SpaceX did indeed want to "move toward super heavy lift"—the specific potential design configurations of

3509-550: The Kwajalein Atoll in the Marshall Islands . 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. The initial orbit was reported to be about 330 × 650 km. Following

3630-536: The Trailblazer (Jumpstart-1) satellite for the US Air Force , the NanoSail-D and PREsat nanosatellites for NASA and a space burial payload for Celestis . The rocket did not reach orbit. However, the first stage, with the new Merlin 1C engine, performed perfectly. When preparing for launch, an earlier launch attempt was delayed by the unexpected slow loading of helium onto the Falcon 1; thus exposing

3751-724: 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

SpaceX Merlin - Misplaced Pages Continue

3872-460: The perigee of the 22 Starlink satellites for deployment. On X, Elon Musk and SpaceX both confirmed the engine failed explosively during a second attempted relight, albeit in a manner that did not appear to damage the second stage of the vehicle as the stage went on to deploy the satellites on board. SpaceX uses a triple-redundant design in the Merlin engine computers. The system uses three computers in each processing unit, each constantly checking on

3993-401: The 2.7-meter-long (9 ft) niobium alloy expansion nozzle is radiatively cooled . The engine delivers a vacuum thrust of 411 kN (92,500 lbf) and a vacuum specific impulse of 342 s (3.35 km/s). The first production Merlin Vacuum engine underwent a full-duration orbital-insertion firing (329 seconds) of the integrated Falcon 9 second stage on January 2, 2010. It

4114-534: The 2.7-meter-long (9 ft) niobium-alloy-sheet nozzle of the Merlin Vacuum engine. The engineering solution was to cut off the lower 1.2 m (4 ft) of the nozzle and launch two days later, as the extra performance that would have been gained from the longer nozzle was not necessary to meet the objectives of the mission. The modified engine successfully placed the second stage into an orbit of 11,000 km (6,800 mi) altitude. The Merlin 1D engine

4235-639: The Apollo Descent Propulsion System was qualified for flight. From 1968 to 1970, a 250,000 lbf (1,112,055 N) engine was tested. In 1972 the Apollo Descent Propulsion System ended production, but starting in 1974, and continuing through 1988, the TR-201 , a simplified, low cost derivative of it, featuring ablative cooling and fixed thrust, was used in the second stage of the Delta 2914 and 3914 launch vehicles. In October 1972,

4356-439: The Falcon 1 and 1e would fly as secondary payloads on the Falcon 9. Historically, the Falcon 1 was originally planned to launch about 600 kilograms (1,300 lb) to low-Earth orbit for US$ 6,000,000 but later declined to approximately 420 kilograms (930 lb) as the price increased to approximately US$ 9,000,000. It was SpaceX's offering intended to open up the smallsat launch market to competition . The final version of

4477-564: 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 450 kg or 990 lb to orbit), instead of building something larger and more complicated, and then running out of money and going bankrupt. The first stage

4598-410: The Falcon 1, the Falcon 1e, was projected to provide approximately 1,000 kg (2,200 lb) 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 420 kg (930 lb) as the price increased to around $ 9 million. Later,

4719-583: The Falcon 1e was to provide approximately 1,000 kg (2,200 lb) 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 3 W was the original launch site for Falcon 1, but it

4840-482: The Falcon 1e. The helium pressurization system pumps propellant to the engine, supplies heated 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. The pressure tanks are composite overwrapped pressure vessels made by Arde corporation with inconel alloy and are

4961-631: The Falcon 9 and Falcon Heavy. The pintle injector was also used on the Reaver 1 engine by Firefly Aerospace . [REDACTED]  This article incorporates public domain material from websites or documents of the National Aeronautics and Space Administration . List of Falcon 1 launches#Third flight Falcon 1 was a two-stage small-lift launch vehicle that was operated from 2006 to 2009 by SpaceX , an American aerospace manufacturer . On 28 September 2008, Falcon 1 became

SpaceX Merlin - Misplaced Pages Continue

5082-541: The Merlin 1A was mounted on a Falcon 1 first stage. The SpaceX turbopump was an entirely new, clean-sheet design contracted to Barber-Nichols, Inc. in 2002, who performed all design, engineering analysis, and construction; the company had previously worked on turbopumps for the RS-88 (Bantam) and NASA Fastrac engine programs. The Merlin 1A turbopump used a unique friction-welded main shaft, with Inconel  718 ends and an integral aluminum RP-1 impeller in

5203-412: The Merlin 1C had a sea-level thrust of 350 kN (78,000 lbf), a vacuum thrust of 400 kN (90,000 lbf) and a vacuum specific impulse of 304 s (2.98 km/s). In this configuration, the engine consumed 140 kg (300 lb) of propellant per second. Tests have been conducted with a single Merlin 1C engine successfully running a total of 27 minutes (counting together

5324-401: The Merlin 1C, which is regeneratively cooled. Therefore, the Merlin 1B was never used on a launch vehicle. Three versions of the Merlin 1C engine were produced. The Merlin engine for Falcon 1 had a movable turbopump exhaust assembly, which was used to provide roll control by vectoring the exhaust. The Merlin 1C engine for the Falcon 9 first stage is nearly identical to

5445-413: The Merlin 1D was used on Falcon 9 Full Thrust and first flew on Flight 20 . In May 2016, SpaceX announced plans to further upgrade the Merlin 1D by increasing vacuum thrust to 914 kN (205,000 lbf) and sea-level thrust to 845 kN (190,000 lbf); according to SpaceX, the additional thrust will increase the Falcon 9 LEO payload capability to about 22 metric tons on

5566-525: 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

5687-535: 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,

5808-409: 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,

5929-445: The company will need to build hundreds of engines a year in order to support a Falcon 9/Falcon Heavy build rate of 30 rocket cores per year by the end of 2016. Each Falcon 9 booster uses nine Merlin engines, and the second stage uses one Merlin vacuum engine. The second stage is expended, so each launch consumes one Merlin Vacuum engine. SpaceX designed the booster with its engines to be recovered for reuse by propulsive landing, and

6050-445: The correction. 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. 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 289 km (180 mi) and

6171-413: The cylindrical stream of propellant A. In the typical pintle-based engine design, only a single central injector is used, differing from "showerhead" injector plates which use multiple parallel injector ports. Throttleability can be obtained either by placing valves before the injector, by moving the inner pintle or outer sleeve, or both. Many people have experienced throttleable pintle sprayers in

SECTION 50

#1732779895756

6292-436: The design of high-performance booster engines. Attempts to use direct injection of cryogenic hydrogen in other types of injectors had until then consistently resulted in the onset of combustion instabilities. In late 1991 and early 1992, a 16,000 lbf (71,172 N) LOX / LH2 test engine was successfully operated with direct injection of liquid hydrogen and liquid oxygen propellants. A total of 67 firings were conducted, and

6413-449: The device from blowing itself apart during high energy tests, the outer tube was retracted, thus constituting a primitive pintle injector. Peter Staudhammer, under the supervision of Program Manager Elverum, had a technician cut multiple slots across the end of an available inner tube and subsequent tests of this new configuration showed a substantial improvement in mixing efficiency. By 1960, Elverum, Grant, and Staudhammer had moved to

6534-584: The dual mode TR-308 was used to place NASA 's Chandra spacecraft on its final orbit. The early FSO injector and gel propellant development work of the late 1980s and early 1990s led to the world's first missile flights using gelled oxidizer and gelled fuel propellants on the Army's/AMCOM's Future Missile Technology Integration (FMTI) program, with the first flight in March 1999 and the second flight in May 2000. In

6655-456: The duration of the various tests), which equals ten complete Falcon 1 flights. The Merlin 1C chamber and nozzle are cooled regeneratively by 45 kg (100 lb) per second of kerosene flow and are able to absorb 10 MW (13,000 hp) of heat energy . A Merlin 1C was first used as part of the unsuccessful third attempt to launch a Falcon 1. In discussing the failure, Elon Musk noted: "The flight of our first stage, with

6776-463: The early 2000s TRW continued development of large LOX / LH2 pintle engines, and test-fired the TR-106 at NASA's John C. Stennis Space Center . This was a 650,000 lbf (2,892,000 N) engine, a 16:1 scale-up from the largest previous LOX / LH2 pintle engine and about a 3:1 scale-up from the largest previous pintle engine ever tested. This injector's pintle diameter was 22 inches (56 cm), by far

6897-488: The engine demonstrated excellent performance and total absence of combustion instabilities. Subsequently, this same test engine was adapted for and was successfully tested with LOX / LH2 at 40,000 lbf (177,929 N) and with LOX / RP-1 at 13,000 and 40,000 lbf. (57,827 and 177,929 N). At the same time, TR-306 liquid apogee engines were used on the Anik E-1/E-2 and Intelsat K spacecraft. In August 1999

7018-509: The engine to be operated in pulses, and this is usually done in pintle-based RCS thrusters and missile divert thrusters. In a variant of the Face Shutoff pintle, the pintle itself is hydraulically actuated by the fuel via a pilot valve, and no extra valves are required between the engine and tanks. This is called an FSO (Face Shutoff Only) pintle. In some variants the pintle has grooves or orifices cut into it to produce radial jets in

7139-423: The engine was shut down after a sudden pressure loss and that only the aerodynamic shell was destroyed, generating the debris seen in the video; the engine did not explode, as SpaceX ground control continued to receive data from it throughout the flight. The primary mission was unaffected by the anomaly due to the nominal operation of the remaining eight engines and an onboard readjustment of the flight trajectory, but

7260-411: The factory had been configured to achieve a maximum production rate of up to 40 rocket cores per year, enough to use the 400 annual engines envisioned by the earlier engine plan. By October 2014, SpaceX announced that it had manufactured the 100th Merlin 1D engine and that engines were now being produced at a rate of four per week, soon to be increased to five. In February 2016, SpaceX indicated that

7381-470: 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

SECTION 60

#1732779895756

7502-446: The first privately developed fully liquid-fueled launch vehicle to successfully reach orbit. 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

7623-403: The first privately funded and developed liquid-propellant rocket to reach orbit. The fifth launch was its first commercial flight, and placed RazakSAT into low Earth orbit . 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

7744-467: The first recovered booster was reused in March 2017. By 2020, only five of the 26 Falcon 9 launched that year used new boosters. By 2021, only two of the 31 Falcon 9 launches used new boosters. At the American Institute of Aeronautics and Astronautics Joint Propulsion conference on July 30, 2010, SpaceX McGregor rocket development facility director Tom Markusic shared some information from

7865-495: 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. The second stage Kestrel engine burns for about six minutes, inserting

7986-426: 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

8107-403: The flow of propellant B, this allows for extra unburned fuel to impinge on the walls of the combustion chamber, and provide fuel film cooling. The pintle pictured here is of this type. Compared to some injector designs, pintle injectors allow greater throttling of bipropellant flow rates, although throttling rocket engines in general is still very difficult. If only one central injector is used,

8228-411: The form of standard garden hose-end sprayers. In pintle engines that do not require throttling, the pintle is fixed in place, and propellant valves for startup and shutdown are placed somewhere else. A movable pintle allows for throttleability, and, if the moving part is the sleeve, the pintle itself can act as the propellant valve. This is called a Face Shutoff pintle. A fast-moving sleeve allows for

8349-407: 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

8470-406: The geometries of the outer propellant's annular gap and the central propellant slots (and/or continuous gap, if used). As this requires only two new pieces to be made, trying variations is usually cheaper and less time-consuming than with regular injectors. Because combustion tends to occur in the surface of a frustum , peak thermal stresses are localized on the combustion chamber wall rather than

8591-459: The house. So it was a shitty summer. 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

8712-474: The initial stages of planning for a new engine. SpaceX’s Merlin 2 LOX /RP-1-fueled engine on a gas-generator cycle , capable of a projected 7,600 kN (1,700,000 lbf) of thrust at sea level and 8,500 kN (1,920,000 lbf) in a vacuum and would provide the power for conceptual super-heavy-lift launch vehicles from SpaceX, which Markusic dubbed Falcon X and Falcon XX . Such a capability, if built, would have resulted in an engine with more thrust than

8833-434: The injector shutoff element provided the only control of propellant flow. The large bipropellant valve normally required in such engines was replaced by a small pilot valve that used high pressure fuel ( MMH ) to hydraulically actuate the moveable injector sleeve. This feature, called FSO (Face Shutoff Only) greatly improved overall thruster response and significantly reduced engine size and mass. Another design challenge from

8954-454: The largest built to date. In 2002 the larger TR-107 was designed. Tom Mueller , who had worked on the TR-106 and TR-107, was hired by SpaceX and started development of the Merlin and Kestrel engines. The Merlin engine was the only pintle injector engine in operation, used for all SpaceX Falcon 9 and Falcon Heavy flights. In the early 2020s, the Merlin engine continued to be used on

9075-498: 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

9196-437: 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

9317-532: 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. 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

9438-415: The mass flow inside the combustion chamber will have two main recirculation zones which decrease acoustic instability without necessarily requiring acoustic cavities or baffles. The pintle injector design can deliver high combustion efficiency (typically 96–99%). If fuel is chosen for the inner flow (which is the case in most pintle-based engines), the injector can be tuned so that any excess fuel which

9559-531: The mid 1980s and early 1990s was that of obtaining miniaturization of rocket engines. As part of the Air Force Brilliant Pebbles program, TRW developed a very small 5 lbf (22 N) N 2 O 4 / hydrazine thruster using a pintle injector. This radiatively-cooled engine weighed 0.3 lb (135 grams) and was successfully tested in August 1993, delivering over 300 seconds I sp with a 150:1 nozzle expansion ratio. The pintle diameter

9680-520: The middle. The turbopump housing was constructed using investment castings , with Inconel at the turbine end, aluminum in the center, and 300-series stainless steel at the LOX end. The turbine was a partial-admission (i.e., working fluid is only admitted through part of the rotation of the turbine; an arc, not the whole circumference) impulse design and turned at up to 20,000 rpm, with a total weight of 68 kg (150 lb). The Merlin 1B rocket engine

9801-421: The more advanced Merlin 1D engine and longer Falcon 9 v1.1 booster. On March 10, 2009, a SpaceX press release announced successful testing of the Merlin Vacuum engine. A variant of the 1C engine, Merlin Vacuum features a larger exhaust section and a significantly larger expansion nozzle to maximize the engine's efficiency in the vacuum of space. Its combustion chamber is regeneratively cooled , while

9922-531: The new Merlin 1C engine that will be used in Falcon 9, was picture perfect." The Merlin 1C was used in the successful fourth flight of Falcon 1 on September 28, 2008. On October 7, 2012, a Merlin 1C (Engine No. 1) of the CRS-1 mission experienced an anomaly at T+00:01:20, which appears on CRS-1 launch video as a flash. The failure occurred just as the vehicle achieved max-Q (maximum aerodynamic pressure). SpaceX's internal review found that

10043-427: The newly-formed Space Technology Laboratories, Inc. (Later TRW, Inc .) to pursue development of monopropellant and bipropellant rocket engines. By 1961, the pintle injector was developed into a design usable in rocket engines, and subsequently, the pintle injector design was matured and developed by a number of TRW employees, adding such features as throttling, rapid pulsing capability, and face shutoff. Throttling

10164-452: 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

10285-516: The others, to instantiate a fault-tolerant design . One processing unit is part of each of the ten Merlin engines (nine on the first stage, one on the second stage) used on the Falcon 9 launch vehicle. The Merlin LOX/RP-1 turbopump used on Merlin engines 1A–1C was designed and developed by Barber-Nichols. It spins at 36,000  revolutions per minute , delivering 10,000 horsepower (7,500 kW). The LOX/RP-1 turbopump on each Merlin engine

10406-411: The oxidizer, represented with blue in the image) flows through an outer tube, coming out as a cylindrical stream, while propellant B (usually the fuel, represented with red in the image) flows within an inner tube and impinges on a central pintle -shaped protrusion, (similar in shape to a poppet valve like those found on four-stroke engines ), spraying out in a broad cone or a flat sheet that intersects

10527-466: The particular launch vehicles shown by Markusic at the propulsion conference were merely conceptual "brainstorming ideas", just a "bunch of ideas for discussion." Since the original discussion, no work on any "Merlin 2" kerolox engine has been pursued and made public. At the 2011 Joint Propulsion Conference, Elon Musk stated that SpaceX were instead working towards a potential staged cycle engine . In October 2012, SpaceX publicly announced concept work on

10648-584: The payload into a low Earth orbit. It is capable of multiple restarts. SpaceX quoted Falcon 1 launch prices as being the same for all customers. 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, and in 2012 announced that payloads originally selected as flying on

10769-456: The pintle injector design was patented and made public. In the early 1980s, a series of design refinements were applied to the pintle injector obtaining exceptionally fast and repeatable pulses on command and linear throttling capability. By enabling shutoff of propellants at their injection point into the combustion chamber, the pintle injector provided excellent pulse response by eliminating injector "dribble volume" effects. Starting in 1981,

10890-419: The previous 14.5 of the Merlin 1C) and chamber pressure in the "sweet spot" of 9.7 MPa (1,410 psi). Merlin 1D was originally designed to throttle between 100% and 70% of maximal thrust; however, further refinements since 2013 now allow the engine to throttle to 40%. The basic Merlin fuel/oxidizer mixture ratio is controlled by the sizing of the propellant supply tubes to each engine, with only

11011-453: 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

11132-487: 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 . 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. The launch occurred from Omelek Island , part of

11253-483: 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. The Falcon 1 upper stage is still in low Earth orbit as of 2021. Following the fifth flight, future launches of Falcon-1 were postponed, and eventually cancelled, and

11374-486: The same as those used in the Delta III . The second stage was powered by a pressure-fed Kestrel engine with 31 kilonewtons (7,000 lbf) of vacuum thrust and a vacuum specific impulse of 330 s. 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. The second stage was not designed to be reusable. At launch,

11495-455: 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. SpaceX attempted the third Falcon 1 launch on 3 August 2008 (GMT) from Kwajalein . This flight carried

11616-494: The secondary-mission payload failed to reach its target orbit due to safety protocols in place to prevent collisions with the ISS. These protocols prevented a second firing of the upper stage for the secondary payload. SpaceX was planning to develop a 560 kN (130,000 lbf) version of Merlin 1C to be used in Falcon 9 Block II and Falcon 1E boosters. This engine and these booster models were dropped in favor of

11737-403: The situation to Ars Technica journalist Eric Berger: 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

11858-775: The solids within the gels plugging the injector passages. FSO pintle injectors were used on a variety of programs, the McDonnell Douglas Advanced Crew Escape Seat – Experimental (ACES-X) program and its successor, the Gel Escape System Propulsion (GESP) program. Another major design adaptation in this time period was the use of pintle injectors with cryogenic liquid hydrogen fuel. Beginning in 1991, TRW joined with McDonnell Douglas and NASA Lewis (now Glenn) Research Center to demonstrate that TRW's pintle engine could use direct injection of liquid hydrogen to simplify

11979-455: The variant used for the Falcon 1, although the turbopump exhaust assembly is not movable. Finally, a Merlin 1C vacuum variant is used on the Falcon 9 second stage. This engine differs from the Falcon 9 first-stage variant in that it uses a larger exhaust nozzle optimized for vacuum operation and can be throttled between 60% and 100%. The Merlin 1C uses a regeneratively cooled nozzle and combustion chamber. The turbopump used

12100-483: 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

12221-439: Was (1.6764 mm) and scanning electron microscopy was needed to verify the dimensions on the ± (0.0762 mm ±0.00762 mm) radial metering orifices. The preceding technology innovations enabled the first exoatmospheric kinetic kill of a simulated reentry warhead off Kwajalein atoll on 28 January 1991 on the first flight of ERIS . In the late '90s, FSO pintle injectors were used with gelled propellants, which have

12342-413: 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 made five launches. The first three failed, however the subsequent two flights were successful, the first successful launch making it

12463-439: Was an upgraded version of the Merlin 1A engine. The turbopump upgrades were handled by Barber-Nichols, Inc. for SpaceX. It was intended for Falcon 1 launch vehicles, capable of producing 380 kN (85,000 lbf) of thrust at sea level and 420 kN (95,000 lbf) in vacuum, and performing with a specific impulse of 261 s (2.56 km/s) at sea level and 303 s (2.97 km/s) in vacuum. The Merlin 1B

12584-495: Was blocked. After removing the blockage the engines started as intended. After this, SpaceX inspected other engines across its fleet and found that two of the engines on the Falcon 9 rocket intended for the Crew-1 launch also had this problem. Those engines were replaced with new M1D engines. On February 16, 2021, on Falcon 9 flight 108 launching Starlink satellites, an engine shut down early due to hot exhaust gasses passing through

12705-419: Was declared to be enough. The full video of the third launch attempt was made public by SpaceX a few weeks after the launch. 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: And

12826-443: 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

12947-402: Was developed by SpaceX between 2011 and 2012, with first flight in 2013. The design goals for the new engine included increased reliability, improved performance, and improved manufacturability. In 2011, performance goals for the engine were a vacuum thrust of 690 kN (155,000 lbf), a vacuum specific impulse ( I sp ) of 310 s (3.0 km/s), an expansion ratio of 16 (as opposed to

13068-495: Was developed with private funding. 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

13189-519: Was employed by the Jet Propulsion Laboratory , and working under the supervision of Art Grant to characterize the reaction rates of new rocket propellants by using a device consisting of two concentric tubes, through which propellants were fed at a known flowrate, and a set of thermocouples to measure their reaction rates. The device encountered problems, because as the propellants were flowing parallel to each other, not much mixing

13310-458: Was enhanced over the 1A with a turbine upgrade, increasing power output from 1,500 kW (2,000 hp) to 1,900 kW (2,500 hp). The turbine upgrade was accomplished by adding additional nozzles, turning the previously partial-admission design to full admission. Slightly enlarged impellers for both RP-1 and LOX were part of the upgrade. This model turned at a faster 22,000 rpm and developed higher discharge pressures. Turbopump weight

13431-480: Was flown on the second stage for the inaugural Falcon 9 flight on June 4, 2010. At full power and as of March 10, 2009, the Merlin Vacuum engine operates with the greatest efficiency of any American-made hydrocarbon-fueled rocket engine. An unplanned test of a modified Merlin Vacuum engine was made in December 2010. Shortly before the scheduled second flight of the Falcon 9 , two cracks were discovered in

13552-404: Was happening. Elverum then placed a tip at the end of the innermost tube, attached to an internal support, which forced the inner propellant to flow outwards and mix with the outer propellant. This device worked fine for low energy propellants, but when high energy combinations started being tested, it proved impractical due to nearly instantaneous reaction times at the mixing point. In order to keep

13673-628: 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,

13794-580: 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 Para­;chute Corp­oration, uses

13915-435: Was powered by a single pump-fed Merlin 1C engine burning RP-1 and liquid oxygen providing 410 kilonewtons (92,000 lbf) of sea-level thrust and a specific impulse of 245 s (vacuum I sp 290 s). The first stage burns to depletion, taking around 169 seconds to do so. The second stage Falcon 1 tanks were built with a cryogenic -compatible 2014 aluminum alloy , with the plan to move to aluminum-lithium alloy on

14036-430: Was reduced to practice and developed by Space Technology Laboratories (STL), then a division of Ramo-Wooldridge Corp., later TRW , starting in 1960. There have been pintle-based engines built ranging from a few newtons of thrust up to several millions, and the pintle design has been tested with all the common and many exotic propellant combinations, including gelled propellants. Pintle-based engines were first used on

14157-660: Was tested in the 1961 MIRA 500 , at 25 to 500 lbf (111 to 2,224 N ) and its 1962 successor, the MIRA 5000 , at 250 to 5,000 lbf (1,112 to 22,241 N). In 1963, TRW introduced the MIRA 150A as a backup for the Thiokol TD-339 vernier thruster to be used in the Surveyor probes , and started development of the Apollo Lunar Excursion Module 's Descent Propulsion System . Near this time,

14278-512: 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

14399-481: 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

14520-413: Was trapped and ignited, causing the engine to be shut down. To address the issue, in a following launch SpaceX indicated that the cleaning process was not done. On October 2, 2020, the launch of a GPS-III satellite was aborted at T-2 seconds due to a detected early startup on 2 of the 9 engines on the first stage. The engines were removed for further testing and it was found that a port in the gas generator

14641-405: Was unchanged at 68 kg (150 lb). Another notable change over the 1A was the move to TEA – TEB ( pyrophoric ) ignition over torch ignition. Initial use of the Merlin 1B was to be on the Falcon 9 launch vehicle, on whose first stage there would have been a cluster of nine of these engines. Due to experience from the Falcon 1's first flight, SpaceX moved its Merlin development to

#755244