XCOR Lynx

The XCOR Lynx was a proposed suborbital horizontal-takeoff, horizontal-landing (HTHL), rocket-powered spaceplane that was under development by the California-based company XCOR Aerospace to compete in the emerging suborbital spaceflight market. The Lynx was intended to carry one pilot, a ticketed passenger, and/or a payload above 100 kilometres (62 mi) altitude. The concept has been under development since 2003 when a two-person suborbital spaceplane was announced under the name Xerus.

In January 2016, XCOR changed plans for the first flight of the Lynx spaceplane. It was initially planned for the second quarter of 2016 from the Midland spaceport in Texas, but, in early 2016, it was pushed to an "undisclosed and tentative" date at the Mojave spaceport.

In May 2016, XCOR announced development of the Lynx had been halted with layoffs of approximately one-third of the staff; the company intended to concentrate on development of their liquid hydrogen rocket under contract with United Launch Alliance, instead.

Following the bankruptcy of XCOR Aerospace in 2017, the assets of the company were sold to the nonprofit organization Build A Plane, which will focus on education rather than suborbital flight.

In 2003, XCOR proposed the Xerus (pronunciation: zEr'us) suborbital spaceplane concept. It was to be capable of transporting one pilot and one passenger as well as some science experiments. It would even be capable of carrying an upper stage which would launch near apogee and, therefore, would potentially be able to carry satellites into low Earth orbit. As late as 2007, XCOR continued to refer to their future two-person spaceplane concept as Xerus.

The Lynx spaceplane was initially announced in March 2008, with plans for an operational vehicle within two years. In December 2008, a ticket price of US$95,000 (equivalent to US$138,741 in 2024) per seat was announced, with flights intended to commence in 2010. The build of the Lynx Mark I flight article did not commence until mid-2013 and XCOR claimed that the first flight would take place in 2015. In July 2015, ticket prices increased by 50% to US$150,000 (equivalent to US$198,982 in 2024). In November 2015, three co-founders left their existing positions with the company to start Agile Aero. Dan DeLong (Chief Engineer) and Aleta Jackson left the company entirely, while Jeff Greason, the former CEO, remained on the Board of Directors until he resigned in March 2016. Greason cited problems with the Lynx vehicle body, although the engine had been a success. As of mid-2016, development was suspended in favor of a ULA-contracted hydrolox engine, the 8H21.

Passengers who had hoped to make flights in the Lynx included the winners from the Axe Apollo Space Academy contest and Justin Dowd of Worcester, Massachusetts, the winner of another contest called the Race for Space. Metro International's Race for Space newspaper contest. By July 2015, the passenger ticket was projected to cost US$150,000. As of December 2015, Kayak.com was reportedly selling tickets for flights on the XCOR Lynx starting in 2016.

In May 2016, the company halted development of the Lynx spaceplane and pivoted company focus toward development of its LOX/LH2 engine technology, particularly on a funded project for United Launch Alliance. The company laid off more than 20 people of the 50–60 persons on board before May.