1. A suborbital flight is a flight in which the vehicle reaches outer space, but its trajectory intersects the atmosphere or the surface of the Earth, so that it does not complete one orbital revolution; it falls back to Earth instead. See for further explanation: 〈http://www.orbspace.com/es/Background-Information/Sub-orbital-vs-Orbital.html〉 (this site, and all other sites mentioned in this paper, was last accessed and verified on 15 August 2012).Potential uses for manned suborbital vehicles include: private human spaceflight (or “space tourism”); human-tended microgravity experiments and suborbital science in general; astronaut and pilot training; ultra-fast point-to-point transportation of passengers and cargo delivery; reconnaissance and other military applications.
2. See 〈http://www.esa.int/SPECIALS/Launchers_Home/SEMQDO4N0MF_0.html〉.
3. The limited scope of the paper makes it impossible to cover all legal aspects. We will focus mostly on general regulation and liability issues. Other aspects that are equally important, such as certification and licensing, air and space traffic management, and registration are also briefly addressed.
4. ICAO Council, “The Concept of Sub-orbital Flights”, 30 May 2005, Part 6, “Conclusions”.
5. André Farand, Tourisme spatial: considération juridique sur les vols suborbitaux, in: Philippe Achilleas (ed.), Droit de l'espace, 2009, pp. 362–363.