Leonard Greene understood that nearly 70 years ago when he created the first commercial autothrottle system. Greene founded the New York-based Safe Flight Instrument Company, also known for its angle-of-attack and stall warning systems.
A few definitions first. Boeing calls its installed system an autothrottle, while a similar system on an Airbus is known as autothrust. Autothrottles typically synchronize with the autopilot and operate in either speed or thrust mode and create many practical hands-free benefits, like flight envelope over- and under-speed protection. Typically connected to the aircraft through the flight management system (FMS) computer and an outside air temperature sensor, the autothrottle calculates engine power more accurately than any human. During an instrument approach or on a standard terminal arrival route (STAR), for example, the autothrottles relieve the pilot of the throttle-jockeying work during required speed changes. If the autothrottles are switched off or become inoperative, the flying pilot can easily revert to flying the aircraft by adjusting the throttles manually.