Flight Management System Vector Functions

A method for providing heading inputs unrelated to a preprogrammed flight plan to an aircraft autopilot in roll steering mode comprising:

• communicating a course heading to a flight management system that is transmitting steering commands related to a preprogrammed flight plan to an autopilot operating in roll steering mode;
• and
• instructing the flight management system to transmit steering commands related to the communicated course heading instead of the steering commands related to the preprogrammed flight plan to the autopilot, the autopilot remaining in roll steering mode.

Computer apparatus for providing heading commands to an autopilot of an aircraft, the autopilot having a roll steering mode and a heading mode, the apparatus comprising:

• means for providing a heading vector;
• and
• flight management means for (i) enabling the autopilot in roll steering mode to follow a preprogrammed flight plan, and (ii) for generating a heading command in response to the provided heading vector, the flight management means forwarding the generated heading command to the autopilot to follow the heading command while in roll steering mode such that heading of the heading command is effectively treated as part of the preprogrammed flight plan.