A system (102, 106, 110, 108) comprising: one or more memory devices; and one or more processors configured to: receive cooperative surveillance messages from a transponder of a target aircraft; track, based on the cooperative surveillance messages received from the target aircraft, a speed of the target aircraft in flight ahead of an own aircraft on which the system is positioned; based on the tracked speed of the target aircraft, determine whether the target aircraft has maintained a rate of deceleration or acceleration within a selected range of variation in deceleration or acceleration, for a selected period of time; and activate a merging trajectory management mode of the own aircraft in response to determining that the own aircraft is in a trajectory management mode transition airspace and that the target aircraft has maintained the rate of deceleration or acceleration within the selected range of variation in change of speed, for the selected period of time, wherein the trajectory management mode transition airspace comprises an airspace designated for transitioning from a cruise trajectory management mode to the merging trajectory management mode on approach to an airport. one or more memory devices; and one or more processors configured to: receive cooperative surveillance messages from a transponder of a target aircraft; track, based on the cooperative surveillance messages received from the target aircraft, a speed of the target aircraft in flight ahead of an own aircraft on which the system is positioned; based on the tracked speed of the target aircraft, determine whether the target aircraft has maintained a rate of deceleration or acceleration within a selected range of variation in deceleration or acceleration, for a selected period of time; and activate a merging trajectory management mode of the own aircraft in response to determining that the own aircraft is in a trajectory management mode transition airspace and that the target aircraft has maintained the rate of deceleration or acceleration within the selected range of variation in change of speed, for the selected period of time, wherein the trajectory management mode transition airspace comprises an airspace designated for transitioning from a cruise trajectory management mode to the merging trajectory management mode on approach to an airport. receive cooperative surveillance messages from a transponder of a target aircraft; track, based on the cooperative surveillance messages received from the target aircraft, a speed of the target aircraft in flight ahead of an own aircraft on which the system is positioned; based on the tracked speed of the target aircraft, determine whether the target aircraft has maintained a rate of deceleration or acceleration within a selected range of variation in deceleration or acceleration, for a selected period of time; and activate a merging trajectory management mode of the own aircraft in response to determining that the own aircraft is in a trajectory management mode transition airspace and that the target aircraft has maintained the rate of deceleration or acceleration within the selected range of variation in change of speed, for the selected period of time, wherein the trajectory management mode transition airspace comprises an airspace designated for transitioning from a cruise trajectory management mode to the merging trajectory management mode on approach to an airport.