navigation of such a vehicle – this lifting body". Future Plans Following on from the completion of the reportedly 'flawless' test flight, ESA officials decided that an additional test flight should be performed during the 2019-2020 timeframe. During this mission, the IXV had been envisioned to land in a different manner, descending directly onto a runway instead of performing a splashdown landing as before; this approach is to be achieved either via the installation of a parafoil, or by the adoption of landing gear. The planning for the second spaceflight was originally to begin during March 2015, while design work on the modified vehicle was to commence during mid 2015. Transition to Space Rider In the ESA December 2016 Science Budget funding was approved by the Ministerial Council for the next IXV flight in the form of the commercialised Space Rider orbital vehicle. Following design reviews in 2018 and 2019, a full size mockup was to be dropped from a balloon in 2019 and will have a first flight atop a Vega-C in 2020/2021. It will then conduct approximately 5 science flights at 6 to 12-month intervals before becoming commercially available from 2025 at a cost of $40,000 per kg of payload for launch, operation, and return to Earth. The Space Rider mini shuttle will have a length of between 4 and 5 meters, a payload capacity of 800 kg, a total mass of 2,400 kg, and endurance of 2 to 6-month missions at a 400 km orbit before returning to Earth and being reflown within 4 months. The Vega-C rocket's 4th stage payload dispenser AVUM acts as the service module for the shuttle, providing orbital manoeuvring and braking, power, and communications before being jettisoned for re-entry. The AVUM service module replaces the integrated IXV Propulsion Module and frees 0.8 m3 of internal space in the vehicle for a payload bay. The Space Rider is similar in operation to the US X-37B but half the X37's length and a fifth the X37's mass and payload capacity, which will make it the smallest and lightest spaceplane to ever fly. Payload doors will be opened on achieving orbit exposing instruments and experiments to space before being closed for landing. In December 2020, ESA signed contracts with co-prime contractors Thales Alenia Space and Avio for delivery of the Space Rider flight model. The first flight is now scheduled in late 2023. Specifications See