Sierra Nevada Corporations Dream Chaser Space Plane
SpaceX is not the only company developing a rapidly reusable space transport vehicle. The Sierra Nevada Corporation based in Nevada. Along with SpaceX and Boeing, they have been developing a vehicle that can transport crew and cargo to space. The name of their vehicle is Dream Chaser.
Dream Chaser is designed to resupply the International Space Station with pressurised and non-pressurised cargo. Dream Chaser will launch on an Atlas V, Ariane 5 or Falcon Heavy rocket and then land on any runway capable of landing a Boeing 747. Although the Dream Chaser and the Space Shuttle look quite similar, there are a lot of significant differences. The spaceplane is capable of carrying up to 5,000 kilogrammes of unpressurized cargo. A crewed version of the Dream Chaser is also in development and will be capable of transporting up to seven astronauts to low-Earth orbit.
Dream Chaser was first announced by NASA in late 2004. The Dream Chaser was originally being developed by SpaceDev but SpaceDev was acquired by SNC in 2008 for $38 million. NASA then invested $20 million into the project and a further $80 million in 2011. In August of 2012, NASA announced they would be awarding SNC $212 million to continue working on Dream Chaser. In 2014, ESA began investigating if the Dream Chaser would be a worthy candidate for transporting cargo and crew to the International Space Station on behalf of the European Space Agency. The Trump administration is considering using Dream Chaser to service the Hubble Space Telescope in 2020.
The vehicle was originally going to use two hybrid rocket engines fueled by hydroxyl-terminated polybutadiene and nitrous oxide. They tested the engine and fired it three times in one day. The engines would have been used for in-orbit manoeuvring. Sierra Nevada Corporation decided to drop their in-house developed hybrid engine for the Orbitecs Vortex Engine. The vortex engine uses propane and nitrous oxide instead. On descent and approach to the runway, the crew will only experience 1.5G's compared to the 3G's experienced by the Space Shuttle crew.
The Dream Chaser was dropped from a SkyCrane as part of a test. The Dream Chaser autonomously manoeuvred itself into the correct angle and then proceeded to follow the flight path to land on the runway. Unfortunately, the left landing gear failed to deploy and the vehicle crash landed. However, the vehicle was found mostly intact and still functional to a certain extent.
As of April 2017, the Dream Chaser has a contract with NASA to provide at least six CRS2 missions to the International Space Station. It has also been selected by the UN to allow countries without a space program to fly microgravity experiments in space.