I was recently reading about flight AA flight 547 out of New York. Upon take off/turn it cut its turn into the wake of the jet which took off before it...causing loss of control and an ultimate crash. Apparently the pilot used the rudder and that was the real cause of the loss of control. My question is, barring a pilot's inappropriate use of the rudder how big a threat is the wake of another plane alone when making the turn after take off? Often times those turns are so sharp as it is, I am just curious whether catching the wake of a plane could be the tipping point in it losing control during such a turn.