Helix, I don't know about the 212 but the Sea King had a strake welded to the port side of the tail boom to stop the rotor downwash producing lift on that side in a right crosswind. The strake slows down the air by breaking up the boundary layer and equalising the speed of the rotor downwash on both side of the tail boom. Running out of left pedal in a right crosswind was a regular occurence before the strake was added but now it's good for a 30 kt crosswind.