If all goes to plan this year we should see at least four Commercial Crew vehicle launches as Boeing and SpaceX complete their uncrewed and crewed demo launches. In addition, we should also see an in-flight launch abort from SpaceX as they test the system and Max-Q when the maximum dynamic pressure is felt by the rocket during launch.
So what is the Commercial Crew program?
Following on from the success of the Commercial Cargo (COTS) program, which resulted in Orbital ATK (formally Orbital Sciences) and SpaceX being awarded contracts to launch cargo to the International Space Station (ISS), NASA launched a commercial crew program with the goal of delivering four crew members to the ISS and successfully returning them to Earth at the end of their mission.
As with the COTS program, NASA designed the Commercial Crew program to be milestone based where payments would only be made when the milestones had been achieved. As part of the bidding process, the competitors defined their own milestones detailing when they would achieve to meet those.
The program was broken into multiple phases started with the Commercial Crew Development (CCDev) 1 program which was awarded to five companies Blue Origin, Boeing, Paragon Space Development Corporation, Sierra Nevada Corporation and United Launch Alliance. A total of $50 million was awarded and a total of 53 milestones defined all due to be completed by 2010.
The second phase CCDev 2, $270 mission was awarded in March 2011 to seven companies, three of those were non-funded. The funded awards were given to Blue Origin, Sierra Nevada Corporation, SpaceX, and Boeing with the non-funded awards going to United Launch Alliance, Alliant TechSystems (ATK) and Excalibur Almaz.
In September 2011 the third phase awards were made under the name Commercial Crew Integrated Capabilities (CCiCap), with this phase NASA wanted complete, end-to-end designs for spacecraft, launch vehicles, launch services and operations. Three companies were awarded contracts in this phase for a total of $1.1 billion, Sierra Nevada, SpaceX, and Boeing.
The next phase was awarded to the same three companies and was called the Certification Products Contract (CPC) 1, in this phase they had to define the certification plan for their systems.
The final phase was awarded to two companies Boeing and SpaceX under the name Commercial Crew Transportation Capability (CCtCap). Under this phase, the two companies are required to complete two demonstration launches of their vehicle with the second taking a crew to the ISS.
Boeing is developing a capsule-based vehicle called the Crew Space Transportation (CST)-100 Starliner. The capsule is designed to carry as many as seven crew members, for the commercial crew program however they will only be carrying four.
Full details of the CST-100 can be found here.
The CST-100 will launch atop the Atlas V from Cape Canaveral Air Force Station Launch Complex 41 which has been upgraded to include a crew access tower and arm to allow access to the CST-100 capsule.
SpaceX’s Dragon 2
The SpaceX entry for the Commercial Crew program is an upgraded version of the Dragon capsule that is currently flying to the ISS on a regular basis. When first announced SpaceX planned to use the same thrusters for Launch Abort and Propulsive Landing capabilities, this would have given the capsule the ability to land anywhere that had a pad. However, since then the propulsive landing capability has been dropped in favor of a water landing as the current Dragon capsule does.
The Crew Dragon launch abort system is built directly into the capsule allowing abort capability all the way to orbit. SpaceX tested the system with a pad abort test on 6th May 2015 when the capsule fired the SuperDraco engines before successfully deploying its parachutes and splashing down in the Atlantic Ocean.
Full details of the Crew Dragon can be found here.
The Crew Dragon is designed to carry as many as seven crew members to orbit and safely return them to Earth at the conclusion of their mission. For the Commercial Crew program, SpaceX will only be carrying four crew members to the ISS. Once launched the capsule will use an automated docking system to approach and dock to the ISS, to aid with this NASA has modified the old Shuttle Docking system with the International Docking Adapter. The first IDA was lost during the SpaceX CRS-7 anomaly, however, a 2nd adapter successfully flew to the station on CRS-9 in July 2016 and a replacement for the first is due to fly on CRS-16 in Summer 2018.
There is no doubt that whoever successfully launches the first crewed mission to the ISS will have bragging rights, however, the real winner in this program is the America Space Program which has been without the ability to launch any crew from US soil since the Space Shuttle retired in 2011. In addition at present, there are only two countries with the capability to launch a crew into space China and Russia, once Boeing and SpaceX have completed their programs the US will double that and we still have the Space Launch System (SLS) and potentially a crewed version of Dream Chaser coming in the future.