A suborbital flight describes a trajectory in which an aircraft achieved a great altitude, but does not enter into orbit.
Suborbital flights will be carried out, for example, to test spaceships and rockets on their suitability for space. Some aircraft, however, were designed so that they reach the outer space only suborbital. These include the X-15 (test aircraft NASA ) and the SpaceShipOne ( and private manned rocket plane ).
The mission profile of meteorological rockets, sounding rockets and military missiles also corresponds to that of a suborbital flight.
Suborbital flights seem interesting, under certain conditions, because it can be much easier to reach outer space in this way. The Ansari X Prize has assumed the definition of that space begins at an altitude of 100 kilometers. To achieve an orbit substantially higher velocities near the first cosmic speed ( 28,000 km / h) is necessary. For this reason, sub-orbital aircraft are cheaper to build and require less development work than space vessels to reach reliably into orbit and beyond. In addition, in a manned aircraft re-entry into Earth's atmosphere and the heat needed for this protection plays an equally important role. Thus, the SpaceShipOne comes from without appreciable heat shield, whereas the Space Shuttle or the landing capsule of the Soyuz spacecraft have massive protection measures because of the significantly higher re-entry speed.
Suborbital tourist flights will have their first purpose is that one ever reaches a flight altitude at which one can speak of the edge of space.
To achieve this, the trajectory is steep or vertical aspire to heaven in order to achieve the required height. After reaching the maximum altitude you then end up back on either the starting place or a village not far distant airfield.
The aircraft may turn off its engines before reaching the maximum altitude, then fly on alone by the pulse. During the unpowered flight prevails in the cabin gravity ( a principle that is applied to the parabolic flights for a long time).
The proponents of these flights hope to profit by countless numbers strong space tourists, their wishes as visits of foreign planet or just a flight had hitherto been almost unrealizable in space.
Driven by the potential prize money of $ 10 million participated in 2004 companies and organizations from around the world at the X Prize competition, which was eventually won by Scaled Composites SpaceShipOne with her.
Another application suborbital flights is to shorten flight times intercontinental flights extreme. To fly from Europe to North America, one would need less than an hour.
A disadvantage would be the current high costs, so do not expect a realization in the near future. The example of the fleet of Concorde supersonic aircraft showed that a short flight time is no guarantee of a profitable flight operations.
History of manned suborbital flights
- X-15, 1959-1968; 1963 more than 100 km altitude
- Mercury - Redstone 3 and 4, 1961, Alan Shepard and Virgil Grissom
- SpaceShipOne, 2004, Michael Melvill and Brian Binnie
Future manned suborbital flights
For a long time, NASA dealt with this topic. She experiments with the scramjet technology, which allows supersonic aircraft could fly at high altitude.
Only in recent years, however, started - inspired mainly by the Ansari X-Prize - private investors and companies the development of aircraft, the suborbital flights to carry.