Roll program

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The roll program is a roll maneuver that occurs after the launch of a vertically-launched space rocket. The maneuver is used to place the spacecraft on a proper heading in a heads down position.

During the launch of manned spacecraft, the roll maneuver is completed shortly after the vehicle clears the tower. The pilot reports the roll to mission control by radioing "Roll program", and the capsule communicator acknowledges the roll. The most recognizable occurrence of this is during a Space Shuttle launch at Kennedy Space Center. For instance, during a launch of Space Shuttle Atlantis, the pilot will report "Houston, Atlantis, roll program", and capcom will respond "Roger roll, Atlantis".^[1] During the Space Race, alternative wording was used - for instance, during the launch of Apollo 15, astronaut Dave Scott reported the roll to mission control by saying "... and we have a roll program".^[2]

The roll program is simultaneously accompanied by a pitch maneuver (sometimes referred to as the pitch program)^[3]. For instance, when Apollo 11 completed its roll maneuver of the Saturn V, the NASA commentator noted "Neil Armstrong reporting the roll and pitch program which puts Apollo 11 on a proper heading".^[3]