He left after only a year 'at the helm' [='in charge'] of the corporation.
The ship's captain was 'at the helm'. [=steering the ship]
The ship's captain 'took the helm'. [=steered the ship]
(..) - Gentlemen, gentlemen! - Remember you are in the Vatican. - What is it that you want? - Yes, you will take control. We'll gladly put you at the helm of our little fleet, but our ships must all sail in the same direction. Otherwise, who can say how long your stay with us will last? Very well. (..)1990 The Godfather Part III