The Falcon 9 v1.0 was the first member of the

Falcon 9 Falcon 9 is a partially reusable medium lift launch vehicle that can carry cargo and crew into Earth orbit, produced by American aerospace company SpaceX. The rocket has two stages. The first (booster) stage carries the second stage and payl ...

launch vehicle family, designed and manufactured by

SpaceX Space Exploration Technologies Corp. (SpaceX) is an American spacecraft manufacturer, launcher, and a satellite communications corporation headquartered in Hawthorne, California. It was founded in 2002 by Elon Musk with the stated goal of ...

Hawthorne, California Hawthorne is a city in the Los Angeles metropolitan area, located in southwestern Los Angeles County, California. It is part of a seventeen-city region commonly called the South Bay. As of the 2020 US census, Hawthorne had a population of 88,0 ...

. Development of the medium-lift launcher began in 2005, and it first flew on June 4, 2010. The Falcon 9 v1.0 then launched four

Dragon A dragon is a reptilian legendary creature that appears in the folklore of many cultures worldwide. Beliefs about dragons vary considerably through regions, but dragons in western cultures since the High Middle Ages have often been depicted as ...

cargo spacecraft: one on an orbital test flight, then one demonstration and two operational resupply missions to the

International Space Station The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA ...

under a

Commercial Resupply Services Commercial Resupply Services (CRS) are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station (ISS) on commercially operated spacecraft. The first CRS contracts were signed in 2008 and awarde ...

contract with

NASA The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding t ...

. The two stage vehicle was powered by SpaceX's

Merlin Merlin ( cy, Myrddin, kw, Marzhin, br, Merzhin) is a mythical figure prominently featured in the legend of King Arthur and best known as a mage, with several other main roles. His usual depiction, based on an amalgamation of historic and le ...

engines, burning

liquid oxygen Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is the liquid form of molecular oxygen. It was used as the oxidizer in the first liquid-fueled rocket invented in 1926 by Robert H. Goddard, an applica ...

(LOX) and rocket-grade kerosene (

RP-1 RP-1 (alternatively, Rocket Propellant-1 or Refined Petroleum-1) is a highly refined form of kerosene outwardly similar to jet fuel, used as rocket fuel. RP-1 provides a lower specific impulse than liquid hydrogen (LH2), but is cheaper, is st ...

). Had the F9 V1.0 been used for launching payloads other than the Dragon to orbit, it would have launched to

low Earth orbit A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...

(LEO) and to

geostationary transfer orbit A geosynchronous transfer orbit or geostationary transfer orbit (GTO) is a type of geocentric orbit. Satellite, Satellites that are destined for geosynchronous orbit, geosynchronous (GSO) or geostationary orbit (GEO) are (almost) always put into ...

(GTO). The vehicle was retired in 2013 and replaced by the upgraded Falcon 9 v1.1, which first flew in September 2013. Of its five launches from 2010 to 2013, all successfully delivered their primary payload, though an anomaly led to the loss of one secondary payload.

Design

First stage

The Falcon 9 v1.0 first stage was used on the first five Falcon 9 launches, and powered by nine SpaceX

Merlin 1C Merlin is a family of rocket engines developed by SpaceX for use on its Falcon 1, Falcon 9 and Falcon Heavy launch vehicles. Merlin engines use RP-1 and liquid oxygen as rocket propellants in a gas-generator power cycle. The Merlin eng ...

rocket engines arranged in a 3x3 pattern. Each of these engines had a sea-level thrust of for a total thrust on liftoff of about . The Falcon 9 tank walls and domes were made from aluminum lithium alloy. SpaceX uses an all- friction stir welded tank, the highest strength and most reliable welding technique available. The Falcon 9 v1.0 first stage used a

pyrophoric A substance is pyrophoric (from grc-gre, πυροφόρος, , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolith ...

mixture of

triethylaluminum Triethylaluminium is one of the simplest examples of an organoaluminium compound. Despite its name it has the formula Al2( C2H5)6 (abbreviated as Al2Et6 or TEA), as it exists as a dimer. This colorless liquid is pyrophoric. It is an industrially ...

triethylborane Triethylborane (TEB), also called triethylboron, is an organoborane (a compound with a B–C bond). It is a colorless pyrophoric liquid. Its chemical formula is or , abbreviated . It is soluble in organic solvents tetrahydrofuran and hexane. Pr ...

(TEA-TEB) as a first-stage ignitor.

Second stage

The upper stage was powered by a single Merlin 1C engine modified for vacuum operation, with an

expansion ratio The expansion ratio of a liquefied and cryogenic substance is the volume of a given amount of that substance in liquid form compared to the volume of the same amount of substance in gaseous form, at room temperature and normal atmospheric pressur ...

of 117:1 and a nominal burn time of 345 seconds. For added reliability of restart, the engine has dual redundant

igniters (TEA-TEB). The second stage tank of Falcon 9 is simply a shorter version of the first stage tank and uses most of the same tooling, material and manufacturing techniques. This saves money during vehicle production. The Falcon 9 v1.0 interstage, which connects the upper and lower stage for Falcon 9, is a carbon fiber aluminum core composite structure. Reusable separation

collet A collet is a segmented sleeve, band or ''collar''. One of the two radial surfaces of a collet is usually tapered (i.e a truncated cone) and the other is cylindrical. The term ''collet'' commonly refers to a type of chuck that uses collets t ...

s and a pneumatic pusher system separate the stages. The stage separation system had twelve attachment points (later reduced to just three in the v1.1 launcher).

Control

SpaceX uses multiple redundant

flight computers Flight or flying is the process by which an object moves through a space without contacting any planetary surface, either within an atmosphere (i.e. air flight or aviation) or through the vacuum of outer space (i.e. spaceflight). This can be ...

in a

fault-tolerant design Fault tolerance is the property that enables a system to continue operating properly in the event of the failure of one or more faults within some of its components. If its operating quality decreases at all, the decrease is proportional to the ...

. Each Merlin engine is controlled by three

voting Voting is a method by which a group, such as a meeting or an electorate, can engage for the purpose of making a collective decision or expressing an opinion usually following discussions, debates or election campaigns. Democracies elect holde ...

computers, each of which has two physical processors that constantly check each other. The software runs on

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

and is written in

C++ C++ (pronounced "C plus plus") is a high-level general-purpose programming language created by Danish computer scientist Bjarne Stroustrup as an extension of the C programming language, or "C with Classes". The language has expanded significan ...

. For flexibility,

commercial off-the-shelf Commercial off-the-shelf or commercially available off-the-shelf (COTS) products are packaged or canned (ready-made) hardware or software, which are adapted aftermarket to the needs of the purchasing organization, rather than the commissioning of ...

parts and system-wide "radiation-tolerant" design are used instead of

radiation-hardened Radiation hardening is the process of making electronic components and circuits resistant to damage or malfunction caused by high levels of ionizing radiation (particle radiation and high-energy electromagnetic radiation), especially for environm ...

parts. Four

Draco Draco is the Latin word for serpent or dragon. Draco or Drako may also refer to: People * Draco (lawgiver) (from Greek: Δράκων; 7th century BC), the first lawgiver of ancient Athens, Greece, from whom the term ''draconian'' is derived * D ...

thrusters were to be used for at least the second revision of the Falcon 9 v1.0 rocket second-stage as a

reaction control system A reaction control system (RCS) is a spacecraft system that uses thrusters to provide attitude control and translation. Alternatively, reaction wheels are used for attitude control. Use of diverted engine thrust to provide stable attitude contr ...

. It is unknown whether Falcon 9 ever flew with these thrusters; the second revision of Falcon 9 v1.0 was replaced with the Falcon 9 v1.1, which used

nitrogen Nitrogen is the chemical element with the symbol N and atomic number 7. Nitrogen is a nonmetal and the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at se ...

cold gas thruster A cold gas thruster (or a cold gas propulsion system) is a type of rocket engine which uses the expansion of a (typically inert) pressurized gas to generate thrust. As opposed to traditional rocket engines, a cold gas thruster does not house any c ...

s. The thrusters were used to hold a stable attitude for payload separation or, as a non-standard service, were also designed to be used to spin up the stage and payload to a maximum of 5 rotations per minute (RPM), although none of the five flown missions had a payload requirement for this service.

Development history

Funding

While SpaceX spent its own money to develop its first launch vehicle, the

Falcon 1 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 ...

, the development of the Falcon 9 was accelerated by the purchase of several demonstration flights by NASA. This started with seed money from the

Commercial Orbital Transportation Services Commercial Orbital Transportation Services (COTS) was a NASA program to coordinate the development of vehicles for the delivery of crew and cargo to the International Space Station by private companies. The program was announced on January 18, 200 ...

(COTS) program in 2006. SpaceX was selected from more than twenty companies that submitted COTS proposals. Without the NASA money, development would have taken longer, Musk said. The development costs for Falcon 9 v1.0 were approximately , and NASA verified those costs. If some of the Falcon 1 development costs were included, since F1 development did contribute to Falcon 9 to some extent, then the total might be considered as high as . NASA also evaluated Falcon 9 development costs using the NASA‐Air Force Cost Model (NAFCOM)—a traditional

cost-plus contract A cost-plus contract, also termed a cost plus contract, is a contract such that a contractor is paid for all of its allowed expenses, ''plus'' additional payment to allow for a profit.US civilian and military space procurement—at based on a NASA environment/culture, or using a more commercial approach.

Production

In December 2010, the SpaceX production line was manufacturing one new Falcon 9 (and Dragon spacecraft) every three months, with a plan to double the production rate to one every six weeks in 2012.

Launch history

The v1.0 version of Falcon 9 was launched five times, all successfully carrying a Dragon spacecraft to low-Earth orbit, of which three achieved docking with the International Space Station. One of those missions deployed its secondary payload in a lower orbit than expected due to an engine failure and safety constraints imposed by the ISS primary mission.

Reusability

SpaceX ran a limited set of post-mission booster recovery

flight test Flight testing is a branch of aeronautical engineering that develops specialist equipment required for testing aircraft behaviour and systems. Instrumentation systems are developed using proprietary transducers and data acquisition systems. D ...

s on the early Falcon rocket launches, both

and Falcon 9. The initial parachute-based design approach was ultimately unsuccessful, and the company adopted a new propulsive-return design methodology that would utilize the Falcon 9 v1.1 vehicle for orbital recovery testing, but did use a Falcon 9 v1.0 booster tank for low-altitude low-velocity flight testing in 2012–2013. From early days in the development of the Falcon 9, SpaceX had expressed hopes that both stages would eventually be reusable. The initial SpaceX design for stage reusability included adding lightweight

thermal protection system Atmospheric entry is the movement of an object from outer space into and through the gases of an atmosphere of a planet, dwarf planet, or natural satellite. There are two main types of atmospheric entry: ''uncontrolled entry'', such as the entr ...

(TPS) capability to the booster stage and utilizing parachute recovery of the separated stage. However, early test results were not successful, leading to abandonment of that approach and the initiation of a new design. In 2011 SpaceX began a formal and funded development program—the

SpaceX reusable launch system development program SpaceX is private spaceflight, privately funding the development of Orbital spaceflight, orbital spacecraft, launch systems that can be reusable launch vehicle, reused many times, in a manner similar to the reusability of aircraft. SpaceX has ...

—with the objective of designing reusable first and second stages utilizing propulsive return of the stages to the launch pad. The early program focus, however, is only on return of the first stage. As an early component of that multi-year program, a Falcon 9 v1.0 first stage tank, long, was used to build and test the

Grasshopper Grasshoppers are a group of insects belonging to the suborder Caelifera. They are among what is possibly the most ancient living group of chewing herbivorous insects, dating back to the early Triassic around 250 million years ago. Grasshopp ...

prototype test vehicle, which made eight successful low-altitude takeoffs and vertical landings in 2012–2013 before the vehicle was retired.

References

{{US launch systems SpaceX launch vehicles Vehicles introduced in 2010 Expendable space launch systems Falcon 9