SpaceX Dragon
The SpaceX Dragon, also known as Dragon 1 or Cargo Dragon, was a class of reusable cargo spacecraft developed by SpaceX, an American private space transportation company. Dragon was launched into orbit by the company's Falcon 9 launch vehicle to resupply the International Space Station. It is now superseded by SpaceX Dragon 2.
During its maiden flight in December 2010, Dragon became the first commercially built and operated spacecraft to be recovered successfully from orbit. On 25 May 2012, a cargo variant of Dragon became the first commercial spacecraft to successfully rendezvous with and attach to the ISS. SpaceX is contracted to deliver cargo to the ISS under NASA's Commercial Resupply Services program, and Dragon began regular cargo flights in October 2012. With the Dragon spacecraft and the Orbital ATK Cygnus, NASA seeks to increase its partnerships with domestic commercial aviation and aeronautics industry.
On 3 June 2017, the CRS-11 capsule, largely assembled from previously flown components from the CRS-4 mission in September 2014, was launched again for the first time, with the hull, structural elements, thrusters, harnesses, propellant tanks, plumbing and many of the avionics reused, while the heat shield, batteries and components exposed to sea water upon splashdown for recovery were replaced.
SpaceX has developed a second version called SpaceX Dragon 2, which includes the capability to transport people. Flight testing was scheduled to complete in the first half of 2019 with the first flight of astronauts, on a mission contracted to NASA, scheduled to occur later the same year; however, a test pad anomaly in April 2019, which resulted in the loss of a Dragon 2 capsule, delayed this development.
The last flight of the first version of the Dragon spacecraft launched 7 March 2020 ; it was a cargo resupply mission to ISS. This mission was the last mission of SpaceX of the first Commercial Resupply Services program. Future SpaceX commercial resupply flights to ISS under the second Commercial Resupply Services program will use the SpaceX Dragon 2 version.
Name
SpaceX's CEO, Elon Musk, named the spacecraft after the 1963 song "Puff, the Magic Dragon" by Peter, Paul and Mary, reportedly as a response to critics who considered his spaceflight projects impossible.History
SpaceX began developing the Dragon spacecraft in late 2004, making a public announcement in 2006 with a plan of entering service in 2009. Also in 2006, SpaceX won a contract to use the Dragon spacecraft for commercial resupply services to the International Space Station for the American federal space agency, NASA.NASA ISS resupply contract
Commercial Orbital Transportation Services
In 2005, NASA solicited proposals for a commercial ISS resupply cargo vehicle to replace the then-soon-to-be-retired Space Shuttle, through its Commercial Orbital Transportation Services development program. The Dragon spacecraft was a part of SpaceX's proposal, submitted to NASA in March 2006. SpaceX's COTS proposal was issued as part of a team, which also included MD Robotics, the Canadian company that had built the ISS's Canadarm2.On 18 August 2006, NASA announced that SpaceX had been chosen, along with Kistler Aerospace, to develop cargo launch services for the ISS. The initial plan called for three demonstration flights of SpaceX's Dragon spacecraft to be conducted between 2008 and 2010. SpaceX and Kistler were to receive up to $278 million and $207 million respectively, if they met all NASA milestones, but Kistler failed to meet its obligations, and its contract was terminated in 2007. NASA later re-awarded Kistler's contract to Orbital Sciences.
Commercial Resupply Services Phase 1
On 23 December 2008, NASA awarded a $1.6 billion Commercial Resupply Services contract to SpaceX, with contract options that could potentially increase the maximum contract value to $3.1 billion. The contract called for 12 flights, with an overall minimum of of cargo to be carried to the ISS.On 23 February 2009, SpaceX announced that its chosen phenolic-impregnated carbon ablator heat shield material, PICA-X, had passed heat stress tests in preparation for Dragon's maiden launch. The primary proximity-operations sensor for the Dragon spacecraft, the DragonEye, was tested in early 2009 during the STS-127 mission, when it was mounted near the docking port of the Space Shuttle Endeavour and used while the Shuttle approached the International Space Station. The DragonEye's lidar and thermography abilities were both tested successfully. The COTS UHF Communication Unit and Crew Command Panel were delivered to the ISS during the late 2009 STS-129 mission. The CUCU allows the ISS to communicate with Dragon and the CCP allows ISS crew members to issue basic commands to Dragon. In summer 2009, SpaceX hired former NASA astronaut Ken Bowersox as vice president of their new Astronaut Safety and Mission Assurance Department, in preparation for crews using the spacecraft.
As a condition of the NASA CRS contract, SpaceX analyzed the orbital radiation environment on all Dragon systems, and how the spacecraft would respond to spurious radiation events. That analysis and the Dragon design – which uses an overall fault-tolerant triple-redundant computer architecture, rather than individual radiation hardening of each computer processor – was reviewed by independent experts before being approved by NASA for the cargo flights.
During March 2015, it was announced that SpaceX had been awarded an additional three missions under Commercial Resupply Services Phase 1. These additional missions are SpaceX CRS-13, SpaceX CRS-14 and SpaceX CRS-15 and would cover the cargo needs of 2017.
On 24 February 2016, SpaceNews disclosed that SpaceX had been awarded a further five missions under Commercial Resupply Services Phase 1. This additional tranche of missions had SpaceX CRS-16 and SpaceX CRS-17 manifested for FY2017 while SpaceX CRS-18, SpaceX CRS-19 and SpaceX CRS-20 and were notionally manifested for FY2018.
Commercial Resupply Services Phase 2
The Commercial Resupply Services 2 contract definition/solicitation period commenced in 2014 and a result announced on 14 January 2016. The CRS-2 launches are expected to commence in 2019, and extend to at least 2024. On 14 January 2016, NASA announced that three companies had been awarded contracts for a minimum of six launches each. SpaceX, Orbital ATK and Sierra Nevada Corporation won contracts.The maximum potential value of all the contracts was indicated to be $14Bn but the minimum requirements would be considerably less. No further financial information was disclosed. The missions involved would be from late 2019 through to 2024.
Demonstration flights
The first flight of the Falcon 9, a private flight, occurred in June 2010 and launched a stripped-down version of the Dragon capsule. This Dragon Spacecraft Qualification Unit had initially been used as a ground test bed to validate several of the capsule's systems. During the flight, the unit's primary mission was to relay aerodynamic data captured during the ascent. It was not designed to survive re-entry, and did not.NASA contracted for three test flights from SpaceX, but later reduced that number to two.
The first Dragon spacecraft launched on its first mission – contracted to NASA as COTS Demo Flight 1 – on 8 December 2010, and was successfully recovered following re-entry to Earth's atmosphere. The mission also marked the second flight of the Falcon 9 launch vehicle. The DragonEye sensor flew again on STS-133 in February 2011 for further on-orbit testing.
In November 2010, the Federal Aviation Administration had issued a re-entry license for the Dragon capsule, the first such license ever awarded to a commercial vehicle.
The second Dragon flight, also contracted to NASA as a demonstration mission, launched successfully on 22 May 2012, after NASA had approved SpaceX's proposal to combine the COTS 2 and 3 mission objectives into a single Falcon 9/Dragon flight, renamed COTS 2+. Dragon conducted orbital tests of its navigation systems and abort procedures, before being grappled by the ISS' Canadarm2 and successfully berthing with the station on 25 May to offload its cargo. Dragon returned to Earth on 31 May 2012, landing as scheduled in the Pacific Ocean, and was again successfully recovered.
On 23 August 2012, NASA Administrator Charles Bolden announced that SpaceX had completed all required milestones under the COTS contract, and was cleared to begin operational resupply missions to the ISS.
Returning research materials from orbit
Dragon spacecrafts can return to Earth, which can be all unpressurized disposal mass or up to of return pressurized cargo from the ISS, and is the only current spacecraft capable of returning to Earth with a significant amount of cargo. Other than the Russian Soyuz crew capsule, Dragon is the only currently operating spacecraft designed to survive re-entry. Because Dragon allows for the return of critical materials to researchers in as little as 48 hours from splashdown, it opens the possibility of new experiments on ISS that can produce materials for later analysis on ground using more sophisticated instrumentation. For example, CRS-12 returned mice that have spent time in orbit which will help give insight into how microgravity impacts blood vessels in both the brain and eyes, and in determining how arthritis develops.Operational flights
Dragon was launched on its first operational CRS flight on 8 October 2012, and completed the mission successfully on 28 October. NASA initially contracted SpaceX for 12 operational missions, and later extended the CRS contract with 8 more flights, bringing the total to 20 launches until 2019. In 2016, a new batch of 6 missions under the CRS2 contract was assigned to SpaceX; those missions are scheduled to be launched between 2020 and 2024.Reuse of previously-flown capsules
, SpaceX's eleventh CRS mission, was successfully launched on 3 June 2017 from Kennedy Space Center LC-39A, being the 100th mission to be launched from that pad. This mission was the first to re-fly a recovered Dragon capsule that previously flew on CRS-4 mission. This mission delivered 2,708 kilograms of cargo to the International Space Station, including NICER. The first stage of the Falcon 9 launch vehicle landed successfully at Landing Zone 1. This mission launched for the first time a refurbished Dragon capsule, serial number C106, which had flown in September 2014 on the CRS-4 mission, and was the first time since 2011 a reused spacecraft arrived at the ISS. Gemini SC-2 capsule is the only other reused capsule, but it was only reflown suborbitally in 1966.SpaceX CRS-12, SpaceX's twelfth CRS mission, was successfully launched on the first 'Block 4' version of the Falcon 9 on 14 August 2017 from Kennedy Space Center LC-39A at the first attempt. This mission delivered 2,349 kg of pressurized mass and 961 kg unpressurized. The external payload manifested for this flight was the CREAM cosmic-ray detector. Last flight of a newly-built Dragon capsule; further missions will use refurbished spacecraft.
SpaceX CRS-13, SpaceX's thirteenth CRS mission, was the second use of a previously-flown Dragon capsule, but the first time in concordance with a reused first-stage booster. It was successfully launched on 15 December 2017 from Cape Canaveral Air Force Station Space Launch Complex 40 at the first attempt. This was the first launch from SLC-40 since the Amos-6 pad anomaly. The booster was the previously-flown core from the CRS-11 mission. This mission delivered 1,560 kg of pressurized mass and 645 kg unpressurized. It returned from orbit and splashed down on 13 January 2018, making it the first space capsule to be reflown to orbit more than once.
SpaceX CRS-14, SpaceX's fourteenth CRS mission, was the third reuse of a previously-flown Dragon capsule. It was successfully launched on 2 April 2018 from Cape Canaveral Air Force Station Space Launch Complex 40. It successfully docked with the ISS on 4 April 2018 and remained docked for a month before returning cargo and science experiments back to earth.
SpaceX CRS-15, SpaceX CRS-16, SpaceX CRS-17, SpaceX CRS-18, SpaceX CRS-19, and SpaceX CRS-20 were all flown with previously flown capsules.
Crewed development program
In 2006, Elon Musk stated that SpaceX had built "a prototype flight crew capsule, including a thoroughly tested 30-man-day life-support system". A video simulation of the launch escape system's operation was released in January 2011. Musk stated in 2010 that the developmental cost of a crewed Dragon and Falcon 9 would be between $800 million and $1 billion. In 2009 and 2010, Musk suggested on several occasions that plans for a crewed variant of the Dragon were proceeding and had a two-to-three-year timeline to completion. SpaceX submitted a bid for the third phase of CCDev, CCiCap.Development funding
In 2014, SpaceX released the total combined development costs for both the Falcon 9 launch vehicle and the Dragon capsule. NASA provided while SpaceX provided over to fund both development efforts.Production
In December 2010, the SpaceX production line was reported to be manufacturing one new Dragon spacecraft and Falcon 9 rocket every three months. Elon Musk stated in a 2010 interview that he planned to increase production turnover to one Dragon every six weeks by 2012. Composite materials are extensively used in the spacecraft's manufacture to reduce weight and improve structural strength.By September 2013, SpaceX total manufacturing space had increased to nearly and the factory had six Dragons in various stages of production. SpaceX published a photograph showing the six, including the next four NASA Commercial Resupply Services mission Dragons plus the drop-test Dragon, and the pad-abort Dragon weldment for commercial crew.
Design
The Dragon spacecraft consists of a nose-cone cap, a conventional blunt-cone ballistic capsule, and an unpressurized cargo-carrier trunk equipped with two solar arrays. The capsule uses a PICA-X heat shield, based on a proprietary variant of NASA's Phenolic impregnated carbon ablator material, designed to protect the capsule during Earth atmospheric entry, even at high return velocities from Lunar and Martian missions. The Dragon capsule is re-usable, and can fly multiple missions. The trunk is not recoverable; it separates from the capsule before re-entry and burns up in Earth's atmosphere. The trunk section, which carries the spacecraft's solar panels and allows the transport of unpressurized cargo to the ISS, was first used for cargo on the SpaceX CRS-2 mission.The spacecraft is launched atop a Falcon 9 booster. The Dragon capsule is equipped with 18 Draco thrusters. During its initial cargo and crew flights, the Dragon capsule will land in the Pacific Ocean and be returned to the shore by ship.
For the ISS Dragon cargo flights, the ISS's Canadarm2 grapples its Flight-Releasable Grapple Fixture and berths Dragon to the station's US Orbital Segment using a Common Berthing Mechanism. The CRS Dragon does not have an independent means of maintaining a breathable atmosphere for astronauts and instead circulates in fresh air from the ISS. For typical missions, Dragon is planned to remain berthed to the ISS for about 30 days.
The Dragon capsule can transport of cargo, which can be all pressurized, all unpressurized, or a combination thereof. It can return to Earth, which can be all unpressurized disposal mass, or up to 2,500 kg of return pressurized cargo, driven by parachute limitations. There is a volume constraint of trunk unpressurized cargo and of pressurized cargo. The trunk was first used operationally on the Dragon's CRS-2 mission in March 2013. Its solar arrays produce a peak power of 4 kW.
The design was modified beginning with the fifth Dragon flight on the SpaceX CRS-3 mission to the ISS in March 2014. While the outer mold line of the Dragon was unchanged, the avionics and cargo racks were redesigned to supply substantially more electrical power to powered cargo devices, including the GLACIER and MERLIN freezer modules for transporting critical science payloads.
Variants and derivatives
DragonLab
When used for non-NASA, non-ISS commercial flights, the uncrewed version of the Dragon spacecraft is called DragonLab. It is reusable and free-flying and can carry pressurized and unpressurized payloads. Its subsystems include propulsion, power, thermal and environmental control, avionics, communications, thermal protection, flight software, guidance and navigation systems, and entry, descent, landing, and recovery gear. It has a total combined upmass of upon launch, and a maximum downmass of when returning to Earth. In November 2014 there were two DragonLab missions listed on the SpaceX launch manifest: one in 2016 and another in 2018. However, these missions were removed from the manifest in early 2017, with no official SpaceX statement. The American Biosatellites once performed similar uncrewed payload-delivery functions, and the Russian Bion satellites still continue to do so.Dragon 2: Crew and Cargo
A successor of Dragon called SpaceX Dragon 2 has been developed by SpaceX, designed to carry passengers and crew. It has been designed to be able to carry up to seven astronauts, or some mix of crew and cargo, to and from low Earth orbit. The Dragon 2 heat shield is designed to withstand Earth re-entry velocities from Lunar and Martian spaceflights. SpaceX undertook several U.S. Government contracts to develop the Dragon 2 crewed variant, including a Commercial Crew Development 2 -funded Space Act Agreement in April 2011, and a Commercial Crew integrated Capability -funded space act agreement in August 2014. The phase 2 of the CRS contract will be flown using the Dragon 2 Cargo variant lacking cockpit controls, seats and life support systems.''Red Dragon''
Red Dragon was a cancelled version of the Dragon spacecraft that had been previously proposed to fly farther than Earth orbit and transit to Mars via interplanetary space. In addition to SpaceX's own privately funded plans for an eventual Mars mission, NASA Ames Research Center had developed a concept called Red Dragon: a low-cost Mars mission that would use Falcon Heavy as the launch vehicle and trans-Martian injection vehicle, and the SpaceX Dragon 2-based capsule to enter the atmosphere of Mars. The concept was originally envisioned for launch in 2018 as a NASA Discovery mission, then alternatively for 2022, but was never formally submitted for funding within NASA. The mission would have been designed to return samples from Mars to Earth at a fraction of the cost of NASA's own sample-return mission, which was projected in 2015 to cost $6 billion.On 27 April 2016, SpaceX announced its plan to go ahead and launch a modified Dragon lander to Mars in 2018. However, Musk canceled the Red Dragon program in July 2017 to focus on developing the Starship system instead. The modified Red Dragon capsule would have performed all entry, descent and landing functions needed to deliver payloads of or more to the Martian surface without using a parachute. Preliminary analysis showed that the capsule's atmospheric drag would slow it enough for the final stage of its descent to be within the abilities of its SuperDraco retro-propulsion thrusters.
Dragon XL
On 27 March 2020, SpaceX revealed the Dragon XL resupply spacecraft to carry pressurized and unpressurized cargo, experiments and other supplies to NASA's planned Lunar Gateway under a Gateway Logistics Services contract. The equipment delivered by Dragon XL missions could include sample collection materials, spacesuits and other items astronauts may need on the Gateway and on the surface of the Moon, according to NASA. It will launch on SpaceX Falcon Heavy rockets from pad 39A at the Kennedy Space Center in Florida. The Dragon XL will stay at the Gateway for 6 to 12 months at a time, when research payloads inside and outside the cargo vessel could be operated remotely, even when crews are not present. Its payload capacity is expected to be more than to lunar orbit.List of missions
List includes only completed or currently manifested missions. Launch dates are listed in UTC.Mission | Capsule No. | Launch date | Remarks | Time at ISS | Outcome |
SpX-C1 | C101 | 8 December 2010 | First Dragon mission, second Falcon 9 launch. Mission tested the orbital maneuvering and reentry of the Dragon capsule. After recovery, the capsule was put on display at SpaceX's headquarters. | ||
SpX-C2+ | C102 | 22 May 2012 | First Dragon mission with complete spacecraft, first rendezvous mission, first berthing with ISS. After recovery, the capsule was put on display at Kennedy Space Center. | 5d 16h | |
SpX-1 | C103 | 8 October 2012 | First Commercial Resupply Services mission for NASA, first non-demo mission. Falcon 9 rocket suffered a partial engine failure during launch but was able to deliver Dragon into orbit. However, a secondary payload did not reach its correct orbit. | ; launch anomaly | |
SpX-2 | C104 | 1 March 2013 | First launch of Dragon using trunk section to carry cargo. Launch was successful, but anomalies occurred with the spacecraft's thrusters shortly after liftoff. Thruster function was later restored and orbit corrections were made, but the spacecraft's rendezvous with the ISS was delayed from its planned date of 2 March until 3 March, when it was successfully berthed with the Harmony module. Dragon splashed down safely in the Pacific Ocean on 26 March. | 22d 18h | ; spacecraft anomaly |
SpX-3 | C105 | 18 April 2014 | First launch of the redesigned Dragon: same outer mold line with the avionics and cargo racks redesigned to supply substantially more electric power to powered cargo devices, including additional cargo freezers for transporting critical science payloads. Launch rescheduled for 18 April due to a helium leak. | 27d 21h | |
SpX-4 | C106 | 21 September 2014 | First launch of a Dragon with living payload, in the form of 20 mice which are part of a NASA experiment to study the physiological effects of long-duration spaceflight. | 31d 22h | |
SpX-5 | C107 | 10 January 2015 | Cargo manifest change due to Cygnus CRS Orb-3 launch failure. Carried the Cloud Aerosol Transport System experiment. | 29d 03h | |
SpX-6 | C108 | 14 April 2015 | The robotic SpaceX Dragon capsule splashed down in the Pacific Ocean on Thursday, 21 May 2015. | 33d 20h | |
SpX-7 | C109 | 28 June 2015 | This mission was supposed to deliver the first of two International Docking Adapters to modify Russian APAS-95 docking ports to the newer international standard. The payload was lost due to an in-flight explosion of the carrier rocket. The Dragon capsule survived the blast; it could have deployed its parachutes and performed a splashdown in the ocean, but its software did not take this situation into account. | ||
SpX-8 | C110 | 8 April 2016 | Delivered the Bigelow BEAM module in the unpressurized cargo trunk. First stage landed for the first time successfully on sea barge. A month later, the Dragon capsule was recovered, carrying a downmass containing astronaut's Scott Kelly biological samples from his year-long mission on board of ISS. | 30d 21h | |
SpX-9 | C111 | 18 July 2016 | Delivered docking adapter IDA-2 to modify the ISS docking port Pressurized Mating Adapter for Commercial Crew spacecraft. Longest time a Dragon Capsule was in space. | 36d 6h | |
SpX-10 | C112 | 19 February 2017 | First launch from KSC LC-39A since STS-135 in mid-2011. Berthing to the ISS was delayed by a day due to software incompatibilities. | 23d 8h | |
SpX-11 | C106.2 | 3 June 2017 | The first mission to re-fly a recovered Dragon capsule. | 27d 1h | |
SpX-12 | C113 | 14 August 2017 | Last mission to use a new Dragon 1 spacecraft | ||
SpX-13 | C108.2 ♺ | 15 December 2017 | Second reuse of Dragon capsule. First NASA mission to fly aboard reused Falcon 9. First reuse of this specific Dragon spacecraft. | ||
SpX-14 | C110.2 ♺ | 2 April 2018 | Third reuse of a Dragon capsule, only necessitated replacing its heatshield, trunk, and parachutes. Returned over 4000 pounds of cargo. First reuse of this specific Dragon spacecraft. | ||
C111.2 ♺ | 29 June 2018 | Fourth reuse. First reuse of this specific Dragon spacecraft. | |||
SpX-16 | C112.2 ♺ | 5 December 2018 | Fifth reuse. First reuse of this specific Dragon spacecraft. The first-stage booster landing failed due to a grid fin hydraulic pump stall on reentry. | ||
SpX-17 | C113.2 ♺ | 4 May 2019 | Sixth reuse. First reuse of this specific Dragon spacecraft. | ||
SpX-18 | C108.3 ♺ | 24 July 2019 | Seventh reuse. First capsule to make a third flight. | ||
SpX-19 | C106.3 ♺ | 5 December 2019 | Eighth reuse. Second capsule to make a third flight. | ||
SpX-20 | C112.3 ♺ | 7 March 2020 | Ninth reuse. Third capsule to make a third flight. Final launch of this Dragon version, with future launches using SpaceX Dragon 2. |
Specifications
DragonLab
The following specifications are published by SpaceX for the non-NASA, non-ISS commercial flights of the refurbished Dragon capsules, listed as "DragonLab" flights on the SpaceX manifest. The specifications for the NASA-contracted Dragon Cargo were not included in the 2009 DragonLab datasheet.Pressure vessel
- interior pressurized, environmentally controlled, payload volume.
- Onboard environment: ; relative humidity 25~75%; 13.9~14.9 psia air pressure.
Unpressurized sensor bay (recoverable payload)
- unpressurized payload volume.
- Sensor bay hatch opens after orbit insertion to allow full sensor access to the outer space environment, and closes before Earth atmosphere re-entry.
Unpressurized trunk (non-recoverable)
- payload volume in the trunk, aft of the pressure vessel heat shield, with optional trunk extension to total length, payload volume increases to.
- Supports sensors and space apertures up to in diameter.
Power, communication and command systems
- Power: twin solar panels providing 1,500 W average, 4,000 W peak, at 28 and 120 VDC.
- Spacecraft communication: commercial standard RS-422 and military standard 1553 serial I/O, plus Ethernet communications for IP-addressable standard payload service.
- Command uplink: 300 kbps.
- Telemetry/data downlink: 300 Mbit/s standard, fault-tolerant S-band telemetry and video transmitters.
Radiation tolerance
Including the six computers that make up the main flight computers, Dragon employs a total of 18 triple-processor computers.