Once fueled, an airplane's minimum flight speed depends on the movement of the air around it. Maximum airspeed, on the other hand, is limited largely by technology.

The speed of an airplane in 2026 is determined by a complex interplay of aerodynamic, environmental, and mechanical factors. Primarily, thrust (generated by engines) must overcome drag (air resistance). As an aircraft climbs, the air becomes thinner (less dense), which reduces drag and allows for higher True Airspeed (TAS), though the engines may produce less thrust in the oxygen-poor air. Temperature also plays a role; colder air is denser, improving engine and wing efficiency. Furthermore, aircraft weight dictates the required lift; heavier planes must fly faster to stay aloft. Finally, wind conditions significantly affect Ground Speed (GS)—the actual speed over the earth. A strong tailwind can push a jet to subsonic records, while a headwind can add hours to a flight time despite the plane moving at its standard cruising speed through the air mass itself.