Dream Chaser, a private spacecraft that looks like a stubby version of the space shuttle, is a concept being tested by Sierra Nevada Corp. based on NASA designs of a 1980s spacecraft prototype. The spacecraft, which originally was developed by a company called SpaceDev, is among a group of ships that vied for private flights to the International Space Station. NASA funded SpaceX's and Boeing's concepts in 2014 for the last round of Commercial Crew Program development, sparking a formal protest from Sierra Nevada. In 2016, however, NASA selected Sierra Nevada, SpaceX and Orbital ATK for anticipated cargo missions to fly between 2019 and 2024. No specific flight awards have been made yet. Once ready, Dream Chaser will carry up to seven people to the orbiting complex. It will launch vertically upon an Atlas rocket and then, like the shuttle, land on a runway horizontally. The spacecraft has a bit of a tangled history. Its design is based mainly on the HL-20 — a NASA spacecraft design from the 1980s that was itself based on a Soviet spacecraft called the BOR-4. But the HL-20 design was never used for space. SpaceDev resurrected the design. According to Ars Technica, in 2006 the firm signed a licensing agreement with NASA to reuse HL-20 for the Dream Chaser concept. Sierra Nevada purchased SpaceDev in 2008, which added a new space systems business area to Sierra Nevada's divisions. In August 2012, Sierra Nevada was one of three companies that received money under the Commercial Crew Integrated Capability (CCiCap) award. CCiCap was the third phase of commercial crew development, and was supposed to help companies in the latter stages of spacecraft work to get their ships ready for flight. Sierra Nevada's contract, which was worth up to $212.5 million, paid out money as the company progressed through certain milestones. In September 2014, NASA announced the next and final phase of the commercial spaceflight program would see SpaceX's Dragon and Boeing's CST-100 spacecraft funded for the Commercial Crew Transportation Capability (CCtCap). The goal is to have the spacecraft ready to fly the International Space Station by 2017. In early 2016, NASA announced that Sierra Nevada (along with SpaceX and Orbital ATK) would all be listed as possible providers for cargo missions to ISS between 2019 and 2024.