I don't knopw if this is your friend's problem or not, but I have found that many beginning fliers tend to freeze their left hand on take off. If he had to use some right rudder on initial take off roll, and forgot to release it, the plane could go right. After take off, the rudder will tend to over power anything except a large aileron input. Try it in the air. Put in a lot of rudder and hold it, then level the wings with aileron. More than likely, you'll find it takes a lot of aileron.

Here's another thing to check. Look at your elevator. If you are flying at full, or nearly full, power, you may have down elevator trimmed in. If this is the case, the plane could be raising the tail before lift off. It is very common for a beginner to roll down the runway much too long before lifting off. I see people all the time with one main gear off the ground. At high speed, the plane has to fly slightly nose down to keep from climbing. On take off, the plane can't get the nose down because of the runway so it raises the tail. This can put extra weight on the nose gear causing it to veer one way or the other depending on gear angles. If this is the case, you need to hold enough up elevator at the start of take off roll to neutralize the elevator. I have my students hold 1/3 to 1/2 up elevator and when the plane gets to lift off speed it takes off by itself.