| Name | Year | Flights | Location |
|---|---|---|---|
| Mercury-Redstone 3 Mercury-Redstone 4 |
1961 | 2 | Cape Canaveral |
| X-15 Flight 90 X-15 Flight 91 |
1963 | 2 | Edwards AFB |
| Soyuz 18a | 1975 | 1 | Baikonur Cosmodrome |
| SpaceShipOne Flight 15P SpaceShipOne Flight 16P SpaceShipOne Flight 17P |
2004 | 3 | Mojave Air and Space Port |
| Blue Origin NS-16[1] Blue Origin NS-18 Blue Origin NS-19 |
2021 | 3 | Corn Ranch |
| Blue Origin NS-20 Blue Origin NS-21 |
2022 | 3 | |
| Blue Origin NS-25 Blue Origin NS-26 |
2024 | 2 |
| Name | Year | Flights | Location |
|---|---|---|---|
| X-15 Flight 62 | 1962 | 1 | Edwards AFB |
| X-15 Flight 77 X-15 Flight 87 |
1963 | 2 | |
| X-15 Flight 138 X-15 Flight 143 X-15 Flight 150 X-15 Flight 153 |
1965 | 4 | |
| X-15 Flight 174 | 1966 | 1 | |
| X-15 Flight 190 X-15 Flight 191 |
1967 | 2 | |
| X-15 Flight 197 | 1968 | 1 | |
| Soyuz MS-10 | 2018 | 1 | Baikonur Cosmodrome |
| VSS Unity VP-03 | 2018 | 1 | Mojave Air and Space Port |
| VSS Unity VF-01 | 2019 | 1 | |
| VSS Unity Unity21 VSS Unity Unity22 |
2021 | 2 | Spaceport America |
| VSS Unity Unity25 Galactic 01 Galactic 02 Galactic 03 Galactic 04 Galactic 05 |
2023 | 6 | Spaceport America |
| Galactic 06 Galactic 07 |
2024 | 2 | Spaceport America |
A sub-orbital spaceflight is a spaceflight in which the spacecraft reaches outer space, but its trajectory intersects the surface of the gravitating body from which it was launched. Hence, it will not complete one orbital revolution, will not become an artificial satellite nor will it reach escape velocity.
For example, the path of an object launched from Earth that reaches the Kármán line (about 83 km [52 mi] – 100 km [62 mi][2] above sea level), and then falls back to Earth, is considered a sub-orbital spaceflight. Some sub-orbital flights have been undertaken to test spacecraft and launch vehicles later intended for orbital spaceflight. Other vehicles are specifically designed only for sub-orbital flight; examples include crewed vehicles, such as the X-15 and SpaceShipTwo, and uncrewed ones, such as ICBMs and sounding rockets.
Flights which attain sufficient velocity to go into low Earth orbit, and then de-orbit before completing their first full orbit, are not considered sub-orbital. Examples of this include flights of the Fractional Orbital Bombardment System.
A flight that does not reach space is still sometimes called sub-orbital, but cannot officially be classified as a "sub-orbital spaceflight". Usually a rocket is used, but some experimental sub-orbital spaceflights have also been achieved via the use of space guns.[3]