The SpaceLiner is a hypersonic suborbital spaceplane concept initiated by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt DLR) in 2005 and supported by the EU under the European Space Agency's (ESA) FAST 20XX program since December 2009. The SpaceLiner is designed to be a reusable vehicle consisting of two stages: the booster and the space-plane itself. Both stages are propelled by LOx-LH2 rocket engines.