A system for controlling an autothrottle of an aircraft equipped with a full-authority digital engine control (FADEC) system having a command input that receives sensed power-control input position signaling indicative of a manual throttle setting, the system comprising: an autothrottle controller (310, 710, 810) including processing circuitry, memory, and input/output facilities, the autothrottle controller operative to execute instructions including an autothrottle control program, the autothrottle controller including an input operative to receive sensed PCL position signaling and configured to output automated power command signaling; and a FADEC interface electrically coupled to the autothrottle controller (310, 710, 810) and configured to be electrically coupled to the FADEC system, wherein the FADEC interface is configured to receive sensed PCL position signaling and to receive the automated power command signaling from the autothrottle controller; wherein the autothrottle control program, when executed, causes the autothrottle controller (310, 710, 810) to determine a control-target setting and to generate the automated power-command signaling according to the control-target setting when the system is in an engaged state for autothrottle control; and wherein the automated power command signaling is generated by the autothrottle controller according to the autothrottle control program, wherein the FADEC interface is controllable by the autothrottle controller (310, 710, 810) to select from among the sensed PCL position signaling and the automated power command signaling to be coupled to the FADEC command input; and the automated power command signaling is synthesized to virtualize electrical characteristics of the sensed PCL position signaling such that the automated power command signaling is recognizable by the FADEC system, at the FADEC command input, as sensed PCL position signaling. an autothrottle controller (310, 710, 810) including processing circuitry, memory, and input/output facilities, the autothrottle controller operative to execute instructions including an autothrottle control program, the autothrottle controller including an input operative to receive sensed PCL position signaling and configured to output automated power command signaling; and a FADEC interface electrically coupled to the autothrottle controller (310, 710, 810) and configured to be electrically coupled to the FADEC system, wherein the FADEC interface is configured to receive sensed PCL position signaling and to receive the automated power command signaling from the autothrottle controller; wherein the autothrottle control program, when executed, causes the autothrottle controller (310, 710, 810) to determine a control-target setting and to generate the automated power-command signaling according to the control-target setting when the system is in an engaged state for autothrottle control; and wherein the automated power command signaling is generated by the autothrottle controller according to the autothrottle control program, wherein the FADEC interface is controllable by the autothrottle controller (310, 710, 810) to select from among the sensed PCL position signaling and the automated power command signaling to be coupled to the FADEC command input; and the automated power command signaling is synthesized to virtualize electrical characteristics of the sensed PCL position signaling such that the automated power command signaling is recognizable by the FADEC system, at the FADEC command input, as sensed PCL position signaling.