Control engineering

The thirty-first entry is a comutação sem sobressalto, and the term English uses for it is « bumpless transfer ». Portuguese names the thing by what it lacks, a sobressalto, a start or a jolt; English picks up the homeliest noun it owns and then denies it. « A bump » is the rise in the road that lifts the wheels, and it is also the dull sound of one thing striking another. It is what happens when you « bump into » an old colleague, which is meeting by accident and nothing more. It is the swelling left by an insect and the goosebumps of a cold morning. « The bumper » is the bar across the front of a car, while « a bumper crop » is an unusually large one, the word having quietly turned into an adjective meaning generous. And « to be bumped » from a flight is to be taken off it because the aircraft was oversold. Against all that, « bumpless » claims one thing only: at the moment the operator hands the valve over to the controller, nothing on the chart moves.