Powered-Flight Trajectory

powered-flight segment of a spacecraft, that portion of the space flight when the rocket propulsion motors are operating. In most cases the powered segment is terminated upon entry into the specified orbit and separation of the spacecraft from its carrier rocket. If the location of the launch site does not allow immediate achievement of the intended orbit, the flight includes several powered segments alternating with inactive ones, when the propulsion units are shut down. The powered-flight segment of present-day carrier vehicles normally does not exceed a duration of 10–15 minutes, a length of time of considerably shorter duration than the orbital flight segment. For future spacecraft equipped with electroreactive propulsion, the powered-flight segment might well constitute a considerable portion of the entire flight trajectory.