An aircraft control system comprising: an aircraft control module adapted to receive aircraft operating inputs (102a to 102d) and, based on the received aircraft operating inputs (102a to 102d), generate first control outputs (104a to 104c) for controlling an aircraft; a trained classifier module adapted to receive the aircraft operating inputs (102a to 102d) and generate second control outputs (104d to 104f) for controlling the aircraft; and an aircraft control processing engine adapted to: receive the first control outputs (104a to 104c) and the second control outputs (104d to 104f); determine a first control value representing at least one of the first control outputs (104a to 104c) and a second control value representing at least one of the second control outputs (104d to 104f); determine an operating control value, at a distance between the first and second control values, the distance being determined by an authority parameter stored in the aircraft control system wherein the authority parameter is used to determine how much of the control of the aircraft is dictated by the aircraft control module and how much of the control of the aircraft is dictated by the trained classifier module ; using the determined operating control value to generate operating control outputs (106a to 106c); and control the aircraft using the operating control outputs (106a to 106c). an aircraft control module adapted to receive aircraft operating inputs (102a to 102d) and, based on the received aircraft operating inputs (102a to 102d), generate first control outputs (104a to 104c) for controlling an aircraft; a trained classifier module adapted to receive the aircraft operating inputs (102a to 102d) and generate second control outputs (104d to 104f) for controlling the aircraft; and an aircraft control processing engine adapted to: receive the first control outputs (104a to 104c) and the second control outputs (104d to 104f); determine a first control value representing at least one of the first control outputs (104a to 104c) and a second control value representing at least one of the second control outputs (104d to 104f); determine an operating control value, at a distance between the first and second control values, the distance being determined by an authority parameter stored in the aircraft control system wherein the authority parameter is used to determine how much of the control of the aircraft is dictated by the aircraft control module and how much of the control of the aircraft is dictated by the trained classifier module ; using the determined operating control value to generate operating control outputs (106a to 106c); and control the aircraft using the operating control outputs (106a to 106c). receive the first control outputs (104a to 104c) and the second control outputs (104d to 104f); determine a first control value representing at least one of the first control outputs (104a to 104c) and a second control value representing at least one of the second control outputs (104d to 104f); determine an operating control value, at a distance between the first and second control values, the distance being determined by an authority parameter stored in the aircraft control system wherein the authority parameter is used to determine how much of the control of the aircraft is dictated by the aircraft control module and how much of the control of the aircraft is dictated by the trained classifier module ; using the determined operating control value to generate operating control outputs (106a to 106c); and control the aircraft using the operating control outputs (106a to 106c). <EOS>