Commercial Resupply Services


Commercial Resupply Services are a series of flights awarded by NASA for the delivery of cargo and supplies to the International Space Station on commercially operated spacecraft.
The first phase of CRS contracts were signed in 2008 and awarded $1.6 billion to SpaceX for twelve Dragon 1 and $1.9 billion to Orbital Sciences for eight Cygnus flights, covering deliveries to 2016. The first operational resupply missions were flown by SpaceX in 2012 and Orbital in 2014. In 2015, NASA extended CRS-1 to twenty flights for SpaceX and twelve flights for Orbital ATK.
A second phase of contracts was solicited in 2014. CRS-2 contracts were awarded in January 2016 to Orbital ATK's continued use of Cygnus, Sierra Nevada Corporation's new Dream Chaser, and SpaceX's new Dragon 2, for cargo transport flights beginning in 2019 and expected to last through 2024.

COTS demo flights

NASA has been directed to pursue commercial spaceflight options since at least 1984, with the Commercial [Space Launch Act of 1984] and Launch Services Purchase Act of 1990. By the 2000s funding was authorized for the Commercial Orbital Transportation Services program, followed by the Commercial Crew Development program. The Antares and Falcon 9 launch vehicles and Cygnus and Dragon cargo spacecraft were developed using Space Act Agreements under the COTS program.
The first flight contracted by NASA, COTS Demo Flight 1, took place on December 8, 2010, demonstrating a Dragon capsule's ability to remain in orbit, receive and respond to ground commands, and communicate with NASA's Tracking and [Data Relay Satellite System]. On August 15, 2011, SpaceX announced that NASA had combined the objectives of the COTS Demo Flight 2 and following Flight 3 into a single mission. The rescoped COTS Demo Flight 2 successfully launched on May 22, 2012, delivering cargo to the ISS. The spacecraft reentered on May 31, landed in the Pacific Ocean, and was recovered, completing CRS certification requirements.
Orbital Sciences first launched the Antares rocket from the Mid-Atlantic Regional Spaceport on April 21, 2013, with a test payload. Orbital Sciences completed the Cygnus Orb-D1 demonstration flight on September 29, 2013, and the operational Cygnus CRS Orb-1 was launched January 9, 2014.

CRS-1 selection process

On December 23, 2008, NASA announced the initial awarding of cargo contracts - twelve flights to SpaceX and eight flights to Orbital Sciences Corporation. PlanetSpace, which was not selected, submitted a protest to the Government Accountability Office. On April 22, 2009, the GAO publicly released its decision to deny the protest, allowing the program to continue.

CRS-1 flights

Transport flights began under Commercial Resupply Services phase 1 in 2012:

Cargo Dragon flights

Following the failure, the Antares rocket was upgraded to the 230 series which used newly built RD-181 first-stage engines to provide greater payload performance and increased reliability. The next two spacecraft were launched on the Atlas V. With the switch to more powerful launch vehicles and the introduction of a larger Enhanced Cygnus, enabled Orbital ATK to cover their initial CRS contracted payload obligation by OA-7.
During August 2015, Orbital ATK disclosed that they had received an extension of the resupply program for four extra missions. These flights enable NASA to cover ISS resupply needs until CRS-2 begins.
NASA began a formal process to initiate Phase 2 of the Commercial Resupply Services, or CRS-2, in early 2014. Later that year, an "Industry Day" was held in Houston, with seven high-level requirements disclosed to interested parties.

Requirements

The contracts were expected to include a variety of requirements:
  • delivery of approximately per year of pressurized cargo in four or five transport trips
  • delivery of 24–30 powered lockers per year, requiring continuous power of up to 120 watts at 28 volts, cooling, and two-way communications
  • delivery of approximately per year of unpressurized cargo, consisting of 3 to 8 items, each item requiring continuous power of up to 250 watts at 28 volts, cooling, and two-way communications
  • return/disposal of approximately per year of pressurized cargo
  • disposal of per year of unpressurized cargo, consisting of 3 to 8 items
  • various ground support services

    Proposals

CRS-1 contractors Orbital Sciences and SpaceX each submitted CRS-2 proposals, joined by Sierra Nevada, Boeing, and Lockheed Martin.
SNC's proposal would use a cargo version of its Dream Chaser crew vehicle, the 'Dream Chaser Cargo System'. The proposed cargo Dream Chaser included an additional expendable cargo module for uplift and trash disposal. Downmass would only be provided via the Dream Chaser spaceplane itself. Boeing's proposal likewise used a cargo version of its CST-100 crew vehicle.
Lockheed Martin proposed a new cargo spacecraft called Jupiter, derived from the designs of the NASA's MAVEN and Juno spacecraft. It would have included a robotic arm based on Canadarm technology and a diameter cargo transport module called Exoliner based on the Automated Transfer Vehicle, to be jointly developed with Thales Alenia Space.

Awards

Three companies were awarded contracts on January 14, 2016. Sierra Nevada Corporation's Dream Chaser, the SpaceX Dragon 2, and Orbital ATK Cygnus were selected, each for a minimum of six launches. The maximum potential value of all the contracts was indicated to be $14 billion, but the minimum value is considerably less. CRS-2 launches commenced in 2019 and will extend to at least 2024.
Three more CRS-2 missions for Dragon 2 covering up to CRS-29 were announced in December 2020.
When NASA issued the Commercial Resupply Services phase 2 request for proposal in September 2014, it received interest from five companies: Lockheed Martin, Boeing, Orbital ATK, Sierra Nevada, and SpaceX. NASA made a competitive range determination to remove Boeing and Lockheed Martin.
Orbital ATK, Sierra Nevada, and SpaceX were awarded CRS-2 contracts in January 2016 with initial task orders awarded in June 2016. Each of the three companies is guaranteed at least six cargo missions under the CRS-2 contract. As of December 2017, NASA had awarded $2.6 billion on three contracts with a combined, not-to-exceed value of $14 billion. NASA officials explained that selecting three companies rather than two for CRS-2 increases cargo capabilities and ensures more redundancy in the event of a contractor failure or schedule delay.
The CRS-2 flights commenced in November 2019 with the launch of Cygnus NG-12 mission.
Inside-cargo is typically transported to and from the space station in "the form factor of single Cargo Transfer Bag Equivalent unit for size of bag used to transport cargo from visiting vehicles, such as SpaceX Dragon, Northrop Grumman Cygnus, or JAXA H-II Transfer Vehicle. The bags are sized at and limited in transport mass to each. CTBE units are also used to price, and charge, commercial users of US Orbital Segment stowage space.

CRS-2 flights

Cygnus flights

As a result Russia's invasion of Ukraine, Northrop Grumman was left with only two remaining Antares 230+ launch vehicles which were used for the CRS NG-18 and CRS NG-19 missions. Northrop Grumman acquired four flights from SpaceX with the Falcon 9 rocket while a replacement first stage and its engine are developed for its Antares 330 rocket.
Northrop Grumman plans to launch further missions using the new Antares 300 series rockets with booster stage and engines developed by Firefly Aerospace.