Definition
The flight path of a vehicle that rises into space but does not have enough velocity to enter and remain in orbit around the Earth. The vehicle climbs above the atmosphere, follows a curved arc shaped by gravity, and then descends back to the surface.
Plain English
A flight that goes up into space, arcs over, and comes back down without ever circling the Earth.
Context Anchor
Seen in spaceflight, high-altitude rocket launch, reentry, and airspace coordination discussions.
Derivation
Sub- comes from Latin meaning 'under' or 'below,' and orbital refers to a complete path around the Earth. So suborbital literally means 'below orbit' -- high enough to reach space, but not fast enough to stay there.
Why Pilots Care
Suborbital flights can affect airspace because launch or reentry areas may be closed or restricted. Pilots need to know that the vehicle will come back through the atmosphere, not remain in orbit.
Analogy
Like throwing a ball as hard as you can. It goes up, arcs over, and falls back down. A suborbital flight does the same thing -- just much higher and faster.
Grounding Statement
Picture a vehicle climbing very high, reaching the top of its path, then descending instead of continuing around Earth.
Intuition Check
Suborbital does not mean a lower orbit. It means not an orbit: the path returns to Earth before completing a full trip around it.
Example Sentence 1
The test vehicle followed a suborbital trajectory, reaching an altitude of 100 kilometers before descending under parachutes.
Example Sentence 2
Space tourism vehicles often use a suborbital trajectory to give passengers a short period of weightlessness without entering orbit.