Centaur (rocket stage)

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https://en.wikipedia.org/wiki/Centaur_(rocket_stage) 

 

Centaur III

A single-engine Centaur III being raised for mating to an Atlas V rocket
Manufacturer	United Launch Alliance
Used on	Atlas V- Centaur III Vulcan- Centaur V
General characteristics
Height	12.68 m (499 in)
Diameter	3.05 m (120 in)
Gross mass	2,247 kg (4,954 lb) (single engine) 2,462 kg (5,428 lb) (dual engine)
Propellant mass	20,830 kg (45,920 lb)
Associated stages
Derivatives	Centaur V Advanced Common Evolved Stage
Launch history
Status	Active
Total launches	245 as of January 2018
First flight	May 9, 1962
Centaur III
Engines	1 or 2 RL10
Thrust	99.2 kN (22,300 lbf) (per engine)
Specific impulse	450.5 sec
Burn time	Variable
Fuel	Liquid oxygen and liquid hydrogen

The Centaur is a family of rocket propelled upper stages currently produced by U.S. launch service provider United Launch Alliance, with one main active version and one version under development. The 3.8 m diameter Common Centaur/Centaur III (as referenced in the infobox) flies as the upper stage of the Atlas V launch vehicle, while the 5.4 m diameter Centaur V is being developed as the upper stage of ULA's new Vulcan rocket.

Centaur was the first rocket stage to use liquid hydrogen (LH₂) and liquid oxygen (LOX) propellants, a high-energy combination that is ideal for upper stages but has significant handling difficulties.

Characteristics

Common Centaur is built around stainless steel pressure stabilized propellant tanks with 0.020 inch thick walls that can nevertheless lift payloads of up to 19,000 kg. The thin walls minimize the mass of the tanks, maximizing the stage's overall performance.

A common bulkhead consisting of two stainless steel skins separated by a fiberglass honeycomb is located between the LOX and LH₂ tanks, further reducing the tank mass. Heat transfer between the extremely cold LH₂ and relatively warm LOX is reduced by the fiberglass honeycomb insulating layer.

The main propulsion system consists of one or two Aerojet Rocketdyne RL-10 engines. The stage is capable of up to twelve restarts, limited by propellant, orbital lifetime, and mission requirements. Combined with the insulation of the propellant tanks, this allows Centaur to perform the multi-hour coasts and multiple engine burns required on complex orbital insertions.

The reaction control system (RCS) also provides ullage and consists of twenty hydrazine monopropellant engines located around the stage in two 2-thruster pods and four 4-thruster pods. Hydrazine (340 lb (150 kg)) is stored in a pair of bladder tanks and fed to the RCS engines with pressurized helium gas, which is also used to accomplish some main engine functions.

Current versions

As of 2019, all but two of the many Centaur variants had been retired: Common Centaur/Centaur III (active) and Centaur V (in development). In the future, United Launch Alliance (ULA) intends to replace Vulcan's Centaur V with the similar Advanced Common Evolved Stage, continuing Centaur's legacy.

Current engines

Version	Stage	Dry mass	Thrust	Isp (ve), vac.	Length	Diameter
RL10A-4-2	Centaur III (DEC)	168 kg	99.1 kN	451 s		1.17 m
RL10C-1	Centaur III (SEC), (DCSS)	190 kg	101.8 kN	449.7 s	2.12 m	1.45 m
RL10C-1-1	Centaur V	188 kg	106 kN	453.8 s	2.46 m	1.57 m

Centaur III/Common Centaur

Common Centaur is the upper stage of the Atlas V rocket. Most payloads launch on Single Engine Centaur (SEC) with one RL-10, but a Dual Engine Centaur (DEC) configuration will be used to launch the CST-100 Starliner crewed spacecraft and possibly the Dream Chaser ISS logistics spaceplane. The higher thrust of two engines allows a gentler ascent with more horizontal velocity and less vertical velocity, which reduces deceleration to survivable levels in the event of a launch abort and ballistic reentry occurring at any point in the flight.

Earlier Common Centaurs were propelled by the RL10-A-4-2 version of the RL-10. Since 2014, Common Centaur has flown with the RL10-C-1, an engine that is shared with the Delta Cryogenic Second Stage, to reduce costs. The Dual Engine Centaur (DEC) configuration will continue to use the smaller RL10-A-4-2 to accommodate two engines in the available space.

The Atlas V can fly in multiple configurations, but only one affects the way Centaur integrates with the booster and fairing: the 5.4 m diameter Atlas V payload fairing attaches to the booster and encapsulates the upper stage and payload, routing fairing-induced aerodynamic loads into the booster. If the 4 m diameter PLF is used, the attachment point is at the top (forward end) of Centaur, routing loads through the Centaur tank structure.

The latest Common Centaurs can accommodate secondary payloads using an Aft Bulkhead Carrier attached to the engine end of the stage.

Centaur V

Centaur V will be the upper stage of the new Vulcan launch vehicle currently being developed by the United Launch Alliance to meet the needs of the National Security Space Launch (NSSL) program. Vulcan was initially intended to enter service with an upgraded variant of the Common Centaur, with an upgrade to the Advanced Cryogenic Evolved Stage (ACES) planned after the first few years of flights.

In late 2017, ULA decided to bring elements of the ACES upper stage forward and begin work on Centaur V. Centaur V will have ACES' 5.4 m diameter and advanced insulation, but does not include the Integrated Vehicle Fluids (IVF) feature expected to allow the extension of upper stage on-orbit life from hours to weeks. Centaur V will utilise 2 different versions of the RL10-C engine with nozzle extensions to improve the fuel consumption for the heaviest payloads. This increased capability over Common Centaur will permit ULA to meet NSSL requirements and retire both the Atlas V and Delta IV rocket families earlier than initially planned. The new rocket publicly became the Vulcan Centaur in March 2018.

In May 2018, the Aerojet Rocketdyne RL-10 was announced as Centaur V's engine following a competitive procurement process against the Blue Origin BE-3. Each stage will mount two engines.

History

The Centaur concept originated in 1956 when Convair began studying a liquid hydrogen fueled upper stage. The ensuing project began in 1958 as a joint venture among Convair, the Advanced Research Projects Agency (ARPA), and the U.S. Air Force. In 1959, NASA assumed ARPA's role. Centaur initially flew as the upper stage of the Atlas-Centaur launch vehicle, encountering a number of early developmental issues due to the pioneering nature of the effort and the use of liquid hydrogen. In 1994 General Dynamics sold their Convair division to Lockheed-Martin.

Centaur A to D (Atlas)

An Atlas-Centaur rocket launches Surveyor 1

The Centaur was originally developed for use with the Atlas launch vehicle family. Known in early planning as the 'high-energy upper stage', the choice of the mythological Centaur as a namesake was intended to represent the combination of the brute force of the Atlas booster and finesse of the upper stage.

Initial Atlas-Centaur launches used developmental versions, labeled Centaur-A through -C. The only Centaur-A launch on 8 May 1962 ended in an explosion 54 seconds after liftoff when insulation panels on the Centaur separated early, causing the LH₂ tank to overheat and rupture. After extensive redesigns, the only Centaur-B flight on 26 November 1963 was successful. After three Centaur-C failures, Centaur-D was the first version to enter operational service, with fifty-six launches.

On 30 May 1966, an Atlas-Centaur boosted the first Surveyor lander towards the Moon. This was followed by six more Surveyor launches over the next two years, with the Atlas-Centaur performing as expected. The Surveyor program demonstrated the feasibility of reigniting a hydrogen engine in space and provided information on the behavior of LH₂ in space.

By the 1970s, Centaur was fully mature and had become the standard rocket stage for launching larger civilian payloads into high Earth orbit, also replacing the Atlas-Agena vehicle for NASA planetary probes.

By the end of 1989, Centaur-D and -G had been used as the upper stage for 63 Atlas rocket launches, 55 of which were successful.

Centaur D-1T (Titan III)

A Titan IIIE-Centaur rocket launches Voyager 2

 

The Centaur D was improved for use on the far more powerful Titan III booster in the 1970s, with the first launch of the resulting Titan IIIE in 1974. The Titan IIIE more than tripled the payload capacity of Atlas-Centaur, and incorporated improved thermal insulation, allowing an orbital lifespan of up to five hours, an increase over the 30 minutes of the Atlas-Centaur.

The first launch of Titan IIIE in February 1974 was unsuccessful, with the loss of the Space Plasma High Voltage Experiment (SPHINX) and a mockup of the Viking probe. It was eventually determined that Centaur's engines had ingested an incorrectly installed clip from the oxygen tank.

The next Titan-Centaurs launched Helios 1, Viking 1, Viking 2, Helios 2, Voyager 1, and Voyager 2. The Titan booster used to launch Voyager 1 had a hardware problem that caused a premature shutdown, which the Centaur stage detected and successfully compensated for. Centaur ended its burn with less than 4 seconds of fuel remaining.

Centaur-G (Atlas)

An upgraded Centaur-D, Centaur-G was introduced on the Atlas G and was carried over to the very similar Atlas I.

Shuttle-Centaur

Illustration of Shuttle-Centaur with Ulysses

 

Centaur-G was a proposed Space Shuttle upper stage. Both Challenger and Discovery were modified to carry the stage. To enable its installation in shuttle payload bays, the diameter of the Centaur-G's hydrogen tank was increased to 14 feet (4.3 m), with the LOX tank diameter remaining at 10 feet (3.0 m). Centaur-G was planned to launch the Galileo and Ulysses robotic probes, with a shortened version planned for U.S. DoD payloads and the Magellan probe to Venus.

After the Space Shuttle Challenger accident, and just months before the Shuttle-Centaur was scheduled to fly, NASA concluded that it was far too risky to fly the Centaur on the Shuttle. The probes were launched with the much less powerful solid-fueled IUS, with Galileo needing multiple gravitational assists from Venus and Earth to reach Jupiter.

Centaur T (Titan IV)

The capability gap left by the termination of the Shuttle-Centaur program was filled by a new launch vehicle, the Titan IV. The 401A/B versions used a Centaur-T upper stage with a 14 feet (4.3 m) diameter hydrogen tank. In the Titan 401A version, a Centaur-T was launched nine times between 1994 and 1998. The 1997 Cassini-Huygens Saturn probe was the first flight of the Titan 401B, with an additional six launches wrapping up in 2003 including one SRB failure.

Centaur II (Atlas II/III)

Centaur II was initially developed for use on the Atlas II series of rockets. Centaur II also flew on the initial Atlas IIIA launches.

Centaur III/Common Centaur (Atlas III/V)

Atlas IIIB introduced the Common Centaur, a longer and initially dual engine Centaur II.

Atlas V cryogenic fluid management experiments

Most Common Centaurs launched on Atlas V have hundreds to thousands of kilograms of propellants remaining on payload separation. In 2006 these propellants were identified as a possible experimental resource for testing in-space cryogenic fluid management techniques.

In October 2009, the Air Force and United Launch Alliance (ULA) performed an experimental demonstration on the modified Centaur upper stage of DMSP-18 launch to improve "understanding of propellant settling and slosh, pressure control, RL10 chilldown and RL10 two-phase shutdown operations. DMSP-18 was a low mass payload, with approximately 28% (5400 kg) of LH₂/LOX propellant remaining after separation. Several on-orbit demonstrations were conducted over 2.4 hours, concluding with a deorbit burn. The initial demonstration was intended to prepare for more-advanced cryogenic fluid management experiments planned under the Centaur-based CRYOTE technology development program in 2012–2014, and will increase the TRL of the Advanced Cryogenic Evolved Stage Centaur successor.

Mishaps

Although Centaur has a long and successful flight history, it has experienced a number of mishaps:

• April 7, 1966: Centaur did not restart after coast — ullage motors ran out of fuel.
• May 9, 1971; Centaur guidance failed, destroying itself and the Mariner 8 spacecraft bound for Mars orbit.
• April 18, 1991: Centaur failed due to particles from the scouring pads used to clean the propellent ducts getting stuck in the turbopump, preventing start-up.
• August 22, 1992: Centaur failed to restart (icing problem).
• April 30, 1999: Launch of the USA-143 (Milstar DFS-3m) communications satellite failed when a Centaur database error resulted in uncontrolled roll rate and loss of attitude control, placing the satellite in a useless orbit.
• June 15, 2007: the engine in the Centaur upper stage of an Atlas V shut down early, leaving its payload — a pair of National Reconnaissance Office ocean surveillance satellites — in a lower than intended orbit. The failure was called "A major disappointment," though later statements claim the spacecraft will still be able to complete their mission. The cause was traced to a stuck-open valve that depleted some of the hydrogen fuel, resulting in the second burn terminating four seconds early. The problem was fixed, and the next flight was nominal.
• August 30, 2018: Atlas V Centaur passivated second stage launched on September 17, 2014 broke up, creating space debris.
• March 23–25, 2018: Atlas V Centaur passivated second stage launched on September 8, 2009 broke up.
• April 6, 2019: Atlas V Centaur passivated second stage launched on October 17, 2018 broke up.

Centaur III Specifications

Source: Atlas V551 specifications, as of 2015.

• Diameter: 3.05 m (10 ft)
• Length: 12.68 m (42 ft)
• Inert mass: 2,247 kg (4,954 lb)
• Fuel: Liquid hydrogen
• Oxidizer: Liquid oxygen
• Fuel & oxidizer mass: 20,830 kg (45,922 lb)
• Guidance: Inertial
• Thrust: 99.2 kN (22,300 lbf)
• Burn time: Variable - eg. 842 seconds on Atlas V
• Engine: RL10-C-1
• Engine length: 2.32 m (7.6 ft)
• Engine diameter: 1.53 m (5 ft)
• Engine dry weight: 168 kg (370 lb)
• Engine start: Restartable
• Attitude control: 4 27-N thrusters, 8 40-N thrusters
  • AC Propellant: Hydrazine

Vulcan (rocket)

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Vulcan_(rocket)

Vulcan

Vulcan configuration as of 2015 with sub-5.4 m Centaur
Function	Launch vehicle, partial reuse planned
Manufacturer	United Launch Alliance
Country of origin	United States
Size
Height	58.3 m (191 ft)
Diameter	5.4 m (18 ft)
Mass	546,700 kg (1,205,300 lb)
Stages	2 and boosters
Capacity
Payload to LEO	34,900 kg (76,900 lb) (Vulcan Heavy Centaur)
Payload to GTO	16,300 kg (35,900 lb) (Vulcan Heavy Centaur)
Payload to GEO	7,200 kg (15,900 lb) (Vulcan Heavy Centaur)
Launch history
Launch sites	SLC-41 SLC-3E
First flight	Planned: July 2021
Boosters
No. boosters	0–6
Motor	GEM-63XL
Thrust	2,201.7 kN (495,000 lbf)
Fuel	HTPB
First stage
Diameter	5.4 m (18 ft)
Engines	2× BE-4
Thrust	4,900 kN (1,100,000 lbf)
Fuel	CH4/LOX
Second stage – Centaur V
Diameter	5.4 m (18 ft)
Engines	2× RL-10
Thrust	212 kN (48,000 lbf)
Specific impulse	448.5 seconds (4.398 km/s)
Fuel	LH2/LOX
Second stage – ACES (proposed, mid-2020s)
Diameter	5.4 m (18 ft)
Fuel	LH2/LOX

Vulcan is a next generation heavy-lift launch vehicle under development by the United Launch Alliance (ULA) to meet the demands of the United States Air Force's National Security Space Launch (NSSL) competition and launch program.

The maiden flight is planned to take place in July 2021, launching Astrobotic's Peregrine lunar lander.

Vehicle description

Vulcan is ULA's first launch vehicle design, adapting and evolving various technologies previously developed for the Atlas V and Delta IV rockets of the USAF's EELV program. The first stage propellant tanks share the diameter of the Delta IV Common Booster Core, but will contain liquid methane and liquid oxygen propellants instead of the Delta IV's liquid hydrogen and liquid oxygen.

Vulcan's upper stage is the Centaur V, an upgraded variant of the Common Centaur/Centaur III currently used on the Atlas V. A lengthened version of the Centaur V will be used on the Vulcan Centaur Heavy. Current plans call for the Centaur V to be eventually upgraded with Integrated Vehicle Fluids technology to become the Advanced Cryogenic Evolved Stage (ACES). Vulcan is intended to undergo the human-rating certification process to allow the launch of crew, such as the Boeing's CST-100 Starliner or Sierra Nevada Corporation's Dream Chaser Space System .

The Vulcan booster will have a 5.4 m (18 ft) outer diameter to support the methane fuel burned by the Blue Origin BE-4 engines. The BE-4 was selected to power Vulcan's first stage in September 2018 after a competition with the Aerojet Rocketdyne AR1.

Zero to six Graphite-Epoxy Motor-63XL (GEM-63XL) solid rocket boosters (SRB)s can be attached to the first stage in pairs, providing additional thrust during the first part of the flight and allowing the six-SRB Vulcan Centaur Heavy to launch a higher mass payload than the most capable Atlas V 551 or Delta IV Heavy.

Vulcan will have a 5.4 m diameter fairing available in two lengths. The longer fairing is 21 m long, with a volume of 317 m³.

Payload mass capabilities

As of October 19, 2018, the current Vulcan Centaur payload figures were:

Version	SRBs	Payload to LEO (kg)	Payload to ISS (kg)	Payload to polar LEO (kg)	Payload to GTO (kg)	Payload to GEO (kg)
Vulcan Centaur	2	17,800	15,300	14,300	7,400	2,050
Vulcan Centaur	4
Vulcan Centaur	6	27,500	24,200	22,300	13,300	6,000
Vulcan Centaur Heavy	6	34,900	31,400	27,900	16,300	7,200
NSSL requirement		6,800		17,000	8,165	6,600

These capabilities are driven by the need to meet USAF NSSL requirements, with room for future growth. As can be seen, the direct GEO orbit is the most demanding, with Vulcan Centaur Heavy only 600 kg above the requirement. 

History

The United Launch Alliance inherited the Atlas V and Delta IV launch vehicle families when the company was formed in 2006. Both were first flown in 2002.

By early 2014 it was clear that ULA would have to develop a new launch vehicle to replace its existing fleet. Additionally, the Atlas V booster uses a Russian RD-180 engine, which led to a push to replace the RD-180 with a U.S. built engine during the Ukrainian crisis of 2014. Relying on foreign hardware to launch critical national security spacecraft was also seen as undesirable. Formal study contracts were issued by ULA in June 2014 to several U.S. rocket engine suppliers. ULA was also facing competition from SpaceX, then seen to affect ULA's core national security market of U.S. military launches, and by July 2014 the United States Congress was debating whether to legislate a ban on future use of the RD-180.

In September 2014, ULA announced that it had entered into a partnership with Blue Origin to develop the BE-4 liquid oxygen (LOX) and liquid methane (CH₄) engine to replace the RD-180 on a new first stage booster. At the time, ULA expected the new booster to start flying no earlier than 2019. ULA has consistently referred to Vulcan as a 'next generation launch system'.

Initial concept

On April 13, 2015, CEO Tory Bruno introduced Vulcan, a new launch vehicle that would incorporate proven technologies, with the name selected by an online poll. ULA stated its goal was to sell the basic Vulcan for half the then-current $164 million price of a basic Atlas V rocket. Addition of strap-on boosters for heavier satellites would increase the price. The first launch was initially planned for 2019.

ULA announced an incremental approach to rolling out the vehicle and its technologies. Vulcan deployment was expected to begin with a new first stage based on the Delta IV's fuselage diameter and production process and initially expected to use two BE-4 engines, with the AR-1 as an alternate. The initial second stage was planned to be the Common Centaur/Centaur III from the Atlas V, with its existing RL-10 engine. A later upgrade, the Advanced Cryogenic Evolved Stage (ACES), was conceptually planned for full development in the late 2010s and introduction a few years after Vulcan's first flight.

The planned ACES upper stage was announced to be liquid oxygen (LOX) and liquid hydrogen (LH₂) powered by one to four rocket engines yet to be selected, and would include the Integrated Vehicle Fluids technology that could allow much longer on-orbit life of the upper stage, measured in weeks rather than hours.

SMART Reuse

Also announced during the initial April 13, 2015 unveiling was the 'Sensible Modular Autonomous Return Technology' (SMART) reuse concept. The booster engines, avionics, and thrust structure would be detached as a module from the propellant tanks after booster engine cutoff, with the module descending through the atmosphere under an inflatable heat shield. After parachute deployment, the module would be captured by a helicopter in mid-air. ULA estimated that this would reduce the cost of the first stage propulsion by 90%, with propulsion 65% of the total first stage cost.

Funding

Through the first several years, the ULA board of directors made quarterly funding commitments to Vulcan Centaur development. As of October 2018, the US government had committed approximately US$1.2 billion in a public–private partnership to Vulcan Centaur development, with future funding being dependent on ULA securing an NSSL contract.

By March 2016, the US Air Force had committed up to US$202 million of funding for Vulcan development. At that time, ULA had not yet estimated the total cost of Vulcan development, but CEO Tory Bruno noted that "new rockets typically cost $2 billion, including $1 billion for the main engine." In April 2016, ULA Board of Directors member and President of Boeing's Network and Space Systems (N&SS) division Craig Cooning expressed confidence in the possible of further USAF funding of Vulcan development.

In March 2018, ULA CEO Tory Bruno said that Vulcan-Centaur had been "75 percent privately funded" up to that time. In October 2018 and following a request for proposals and technical evaluation, ULA was awarded $967 million to develop a prototype Vulcan launch system as a part of the National Security Space Launch program. Two other providers, Blue Origin and Northrop Grumman Innovation Systems, were also awarded development funding, with detailed proposals and a competitive selection process to follow in 2019. The USAF's goal with the next generation of Launch Service Agreements is to get out of the business of "buying rockets" and move to acquiring launch services from launch service providers, but U.S. government funding of launch vehicle development continues.

Path to production

In September 2015, ULA and Blue Origin announced an agreement to expand the production capabilities of the BE-4 rocket engine then in development and test.

In January 2016, ULA was designing two versions of the Vulcan first stage. The BE-4 version has a 5.4 m diameter to support the use of less-dense methane fuel.

In late 2017, the upper stage was changed to the larger and heavier Centaur V, and the overall launch vehicle was renamed Vulcan Centaur. The single core Vulcan Centaur will be capable of lifting "30% more" than a Delta IV Heavy, meeting the NSSL requirements.

In May 2018, ULA announced the selection of Aerojet Rocketdyne's RL10 engine for the Vulcan Centaur upper stage. In September 2018, ULA announced the selection of the Blue Origin BE-4 engine for Vulcan's booster.

In October 2018, the USAF released an NSSL launch service agreement with additional requirements, delaying Vulcan's initial launch to April 2021 after an earlier slip to 2020.

On July 8, 2019, images of two Vulcan qualification test articles were released by CEO Tory Bruno on Twitter: the liquefied natural gas (fuel) tank and thrust structure. On July 9, 2019, an image of a Vulcan payload attach fitting (PAF) was released by Peter Guggenbach, the CEO of RUAG Space. On July 31, 2019, two images of the mated LNG tank and thrust structure were released by CEO Tory Bruno on Twitter.

On 2 August 2019, Blue Origin released on twitter an image of a BE-4 engine at full power on a test stand. On 6 August 2019, the first two parts of Vulcan's mobile launch platform (MLP) were transported to the Solid Motor Assembly and Readiness Facility (SMARF) near SLC-40 and SLC-41, Cape Canaveral. The MLP was fabricated in eight sections and will move at 3 mph on existing rail dollies and stand 183 feet tall.

On 12 August 2019, ULA submitted Vulcan Centaur for phase 2 of the USAF's launch services competition. As of that time, Vulcan Centaur was on track for a 2021 launch.

Certification flights

On 14 August 2019, it was announced that the second Vulcan certification flight will be the first of six Dream Chaser CRS-2 flights. Launches are planned to begin in 2021 and will use the four-SRB Vulcan configuration.

On 19 August 2019, it was announced that Astrobotic Technology's Peregrine lander will launch on the first Vulcan certification flight. Peregrine is currently intended to launch in 2021 from SLC-41 at Cape Canaveral Air Force Station.

Boeing CST-100 Starliner

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https://en.wikipedia.org/wiki/Boeing_CST-100_Starliner

Boeing CST-100 Starliner

Starliner sits atop the Atlas V ahead of Boe-OFT
Manufacturer	Boeing
Country of origin	United States
Operator	Boeing
Applications	Crew Transfer Vehicle
Specifications
Spacecraft type	Crewed capsule
Design life	60 hours (free flight) 210 days (docked)
Launch mass	13,000 kg (29,000 lb)
Crew capacity	7
Dimensions	Diameter (CM): 4.56 m (15.0 ft) Length (CM+SM): 5.03 m (16.5 ft)
Volume	11 m3 (390 cu ft)
Regime	Low Earth
Production
Status	In development and testing
Maiden launch	December 20, 2019 11:36:43 UT (uncrewed)

The Boeing CST-100 Starliner (Crew Space Transportation) is a crew capsule manufactured by Boeing as its participation in NASA's Commercial Crew Development (CCDev) program. Its primary purpose is to transport crew to the International Space Station (ISS) and to private space stations such as the proposed Bigelow Aerospace Commercial Space Station.

Starliner is similar in concept to the Orion spacecraft being built for NASA by Lockheed Martin. The capsule has a diameter of 4.56 meters (15.0 ft), which is slightly larger than the Apollo command module and smaller than the Orion capsule. The Starliner is to support larger crews of up to seven people and is being designed to be able to remain in-orbit for up to seven months with reusability of up to ten missions. It is designed to be compatible with four launch vehicles: Atlas V, Delta IV, Falcon 9, and Vulcan.

In the first phase of its CCDev program NASA awarded Boeing US$18 million in 2010 for preliminary development of the spacecraft. In the second phase Boeing was awarded a $93 million contract in 2011 for further spacecraft development. On August 3, 2012, NASA announced the award of $460 million to Boeing to continue work on the CST-100 under the Commercial Crew Integrated Capability (CCiCap) Program. On September 16, 2014, NASA selected the CST-100, along with SpaceX's Crew Dragon, for the Commercial Crew Transportation Capability (CCtCap) program, with an award of $4.2 billion. On July 30, 2019, NASA had no specific dates for Commercial Crew launches, stating that this was under review pending a leadership change.

Starliner's uncrewed test flight launched with the Atlas V N22, on December 20, 2019 from SLC-41 at Cape Canaveral, Florida. During the test, the Starliner experienced an anomaly that precluded a docking with the International Space Station.

Background

CST-100 crew mock up

 

The design draws upon Boeing's experience with NASA's Apollo, Space Shuttle and ISS programs as well as the Orbital Express project sponsored by the Department of Defense. The CST-100 has no Orion heritage, but it is sometimes confused with the earlier and similar Orion-derived Orion Lite proposal that Bigelow Aerospace was reportedly working on with technical assistance from Lockheed Martin. It will use the NASA Docking System for docking and use the Boeing Lightweight Ablator for its heatshield. The Starliner's solar cells will provide more than 2,900 watts of electricity, will be placed on top of the micro-meteoroid debris shield located at the bottom of the spacecraft's service module.

It is designed to be compatible with multiple launch vehicles, including the Atlas V, Delta IV, and Falcon 9, as well as the planned Vulcan. Unlike earlier U.S. space capsules, the CST-100 will make airbag-cushioned landings on the ground rather than into water. Five landing areas are planned in the Western United States, which will give the CST-100 about 450 landing opportunities every year.

The CST-100 includes one space tourist seat, and the Boeing contract with NASA allows Boeing to price and sell passage to low Earth orbit on that seat.

Development

The CST-100 name was first used when the capsule was revealed to the public by Bigelow Aerospace CEO Robert Bigelow in June 2010. The letters CST stand for Crew Space Transportation. Although it has been reported that the number 100 in the name stands for 100 km, the height of the Kármán line which is one of several definitions of the boundary of space, the naming was in fact an arbitrary designation created by the corporate office. The Rocketdyne RS-88 (Bantam) engine will be used for its launch escape system.

Receiving the full fixed-price payments for the CCDev Phase 1 Space Act Agreement required a set of specific milestones to be met during 2010:

• Trade study and down-select between pusher-type and tractor-style launch escape system
• System definition review
• Abort System Hardware Demonstration Test
• Base Heat Shield Fabrication Demonstration
• Avionics Systems Integration Facility demonstration
• CM Pressure Shell Fabrication Demonstration
• Landing System Demonstration (drop test and water uprighting test)
• Life Support Air Revitalization demonstration
• Autonomous Rendezvous and Docking (AR&D) hardware/software demonstration
• Crew Module Mockup demonstration

CST-100 pressure vessel at the former Orbiter Processing Facility 3 in October 2011

 

In July 2010, Boeing stated that the capsule could be operational in 2015 with sufficient near-term approvals and funding, but also indicated they would proceed with development of the CST-100 only if NASA implemented the commercial crew transport initiative that was announced by the Obama administration in its FY11 budget request. Boeing executive Roger Krone stated that NASA investment would allow Boeing to close the business case, while this would be very difficult without NASA. In addition a second destination besides the ISS would be needed to close the business case and Krone said that cooperation with Bigelow was crucial for this.

Boeing was awarded a $92.3 million contract by NASA in April 2011 to continue to develop the CST-100 under CCDev phase 2. On August 3, 2012, NASA announced the award of $460 million to Boeing to continue work on the CST-100 under the Commercial Crew Integrated Capability (CCiCap) Program.

Wind tunnel testing of CST-100's outer mold line in December 2011

 

On October 31, 2011, NASA announced that through a partnership with Space Florida, the Orbiter Processing Facility-3 at Kennedy Space Center would be leased to Boeing for manufacture and test of CST-100 spacecraft.

On September 16, 2014, NASA chose Boeing (CST-100) and SpaceX (Dragon V2) as the two companies that will be funded to develop systems to transport U.S. government crews to and from the International Space Station. Boeing won a $4.2 billion contract to complete and certify CST-100 spacecraft by 2017, while SpaceX won a $2.6 billion contract to complete and certify their crewed Dragon spacecraft. The contracts include at least one crewed flight test with at least one NASA astronaut aboard. Once the Starliner achieves NASA certification, the contract requires Boeing to conduct at least two, and as many as six, crewed missions to the space station. NASA's William H. Gerstenmaier considers the CST-100 proposal as stronger than the two others.

Part of the agreement with NASA allows Boeing to sell seats for space tourists. Boeing proposed including one seat per flight for a space flight participant at a price that would be competitive with what Roscosmos charges tourists.

On September 4, 2015, Boeing announced that the CST-100 would officially be called the CST-100 Starliner, a name that follows the conventions of the 787 Dreamliner produced by Boeing Commercial Airplanes. In November 2015, NASA announced it had dropped Boeing from consideration in the multibillion-dollar Commercial Resupply Services second-phase competition to fly cargo to the International Space Station.

In May 2016, Boeing delayed its first scheduled CST-100 launch from 2017 to early 2018. Then in October 2016, Boeing delayed its program by six months, from early 2018 to late 2018, following supplier holdups and a production problem on the second CST-100. By 2016, they were hoping to fly NASA astronauts to the ISS by December 2018.

In April 2018, NASA suggested the first planned two-person flight of the CST-100 Starliner, slated for November 2018, was now likely to occur in 2019 or 2020. If the delays are maintained it would be expected to carry one additional crew member and extra supplies. Instead of staying for two weeks as originally planned, NASA said the expanded crew could stay at the station for as long as six months as a normal rotational flight.

Testing

Test of the CST-100 capsule at Delamar Dry Lake, Nevada, with airbags deployed in April 2012

 

Test firing of the RS-88 in December 2003

A variety of validation tests have been underway on test articles since 2011.

In September 2011, Boeing announced the completion of a set of ground drop tests to validate the design of the airbag cushioning system. The airbags are located underneath the heat shield of the CST-100, which is designed to be separated from the capsule while under parachute descent at about 5,000 feet (1,500 m) altitude. The airbags are deployed by filling with a mixture of compressed nitrogen and oxygen gas, not with the pyro-explosive mixture sometimes used in automotive airbags. The tests were carried out in the Mojave Desert of southeast California, at ground speeds between 10 and 30 miles per hour (16 and 48 km/h) in order to simulate crosswind conditions at the time of landing. Bigelow Aerospace built the mobile test rig and conducted the tests.

In April 2012, Boeing dropped a mock-up of its CST-100 commercial crew capsule over the Nevada desert at the Delamar Dry Lake near Alamo, Nevada, successfully testing the craft's three main landing parachutes from 11,000 feet (3,400 m).

In August 2013, Boeing announced that two NASA astronauts evaluated communications, ergonomics, and crew-interface aspects of the CST-100, showing how future astronauts will operate in the spacecraft as it transports them to the International Space Station and other low Earth orbit destinations.

Boeing reported in May 2016 that its test schedule would slip by eight months in order to reduce the mass of the spacecraft and aerodynamics issues anticipated during launch and ascent on the Atlas V rocket. The Orbital Flight Test is scheduled for spring 2019. The booster for this Orbital Flight Test, an Atlas V N22 rocket, is being assembled at ULA's facility at Decatur, Alabama. The first crewed flight (Boe-CFT) is scheduled for summer 2019, depending on test results from Boe-OFT. It is planned to last 14 days and carry one NASA astronaut and one Boeing test pilot to the ISS. On April 5, 2018, NASA announced that the first planned two-person flight, originally slated for November 2018, is now likely to occur in 2019 or 2020. If this delay occurs the mission could be expected to carry one additional crew member and supplies. NASA said the expanded crew could stay at the station for as long as six months as a normal rotational flight. This is due to the ending of the agreement for Russia to ferry astronauts to and from the International Space Station in late 2019. NASA has named its first Commercial Crew astronaut cadre of four veteran astronauts to work with SpaceX and Boeing: Robert Behnken, Eric Boe, Sunita Williams, and Douglas Hurley. In July 2018 Boeing announced the assignment of former NASA astronaut Chris Ferguson to the Boe-CFT mission.

In July 2018, a test anomaly was reported in which there was a hypergolic propellant leak due to several faulty abort system valves. Consequentially the first unpiloted orbital mission was delayed to April 2019, and the first crew launch rescheduled to August 2019. In March 2019, Reuters reported these test flights had been delayed by at least three months, and in April Boeing announced that the unpiloted orbital mission is now scheduled for August 2019.

CST-100 Starliner and its service module atop the test stand at Launch Complex 32, White Sands Missile Range, New Mexico, in preparation for the Pad Abort Test.

 

In May 2019, all major hotfire, including simulations of low-altitude abort thruster testing, was completed using a full up service module test article that was "flight-like", meaning that the service module test rig used in the recent hotfire testing included fuel and helium tanks, reaction control system, orbital maneuvering and attitude control thrusters, launch abort engines, and all necessary fuel lines and avionics that the ones that will be used for crewed missions will have. This clears the way for the pad abort test and the subsequent uncrewed and crewed flights later.

A pad abort test took place on November 4, 2019. The capsule accelerated away from its pad, but then one of the three parachutes failed to deploy and the capsule landed with only two parachutes. Landing was however deemed safe, and the test a success. Boeing did not expect the malfunction of one parachute to affect the Starliner development schedule.

First orbital flight test

The orbital flight test launched on December 20, 2019, but after deployment, an 11 hour offset in the mission clock of Starliner caused the spacecraft to compute that "it was in an orbital insertion burn", when it was not. This engine burn consumed more fuel than expected, precluding a docking with the International Space Station. The spacecraft landed at New Mexico's White Sands Missile Range two days after launch. After the successful landing, the spacecraft was named the good ship "Calypso" (after the research vessel RV Calypso for the oceanographic researcher Jacques-Yves Cousteau) by the commander of the USCV-2 mission, NASA astronaut Sunita Williams.

List of flights

List includes only completed or currently manifested missions. Launch dates are listed in UTC.

Mission	Launch date (UTC)	Crew	Remarks	Duration	Outcome
Starliner pad abort test	November 4, 2019, 14:15 UTC	N/A	Pad abort test, White Sands Missile Range, New Mexico. One of three parachutes failed to open due to being rigged incorrectly before launch, but parachute system functioned adequately.	95 Seconds	Success
Boe-OFT	December 20, 2019, 11:36:43 UTC	N/A	Uncrewed orbital test flight of Starliner. The mission's main objective of ISS rendezvous was aborted due to software incorrectly keeping mission time, leading to a late orbital insertion burn with excessive fuel expenditure. Starliner landed in New Mexico two days after launch.	2 days	Partial failure due to a MET anomaly. Rendezvous with ISS cancelled.
Boe-CFT	First half of 2020	Christopher Ferguson Mike Fincke Nicole Mann	First crewed test flight of the CST-100		Planned
USCV-2	Late 2020	Sunita Williams Josh Cassada Thomas Pesquet TBA	First operational flight of the CST-100. This will be a reflight of the OFT vehicle which has been christened 'Calypso' by USCV-2 commander Williams upon its return to earth.		Planned

Crew

CST-100 Starliner mockup and the astronauts initially selected for the first two missions, from left to right: Sunita Williams, Josh Cassada, Eric Boe, Nicole Mann, and Christopher Ferguson.

 

On August 3, 2018, NASA announced the astronauts who will participate in the first Starliner flights. Eric Boe was one of those initially selected, but was replaced by Michael Fincke in January 2019 due to "personal medical reasons".

• First test crew - Boe-CFT: Michael Fincke, Christopher Ferguson, Nicole Aunapu Mann
• First mission crew - USCV-2: Sunita Williams, Josh Cassada, Thomas Pesquet, Andrei Borisenko
  

Space tourism

Space Adventures announced that it has acquired rights to sell tickets to the ISS on board the CST-100 once operational flights begin.

Technology partners

• Aerojet Rocketdyne
• Airborne Systems
• Alliant Techsystems
• Bigelow Aerospace
• Samsung
• Spincraft