On November 7, 2008, about 1615 mountain standard time, the wing of a Southwest Airlines Boeing 737-700, N254WN, Flight #784, made contact with the wing of another Southwest Airlines Boeing 737 during the push-back from the jetway at Salt Lake City International Airport, Salt Lake City, Utah. There were no injuries to the two-person flight crew, the three flight attendants, or the 46 passengers. The contact between the two airplanes resulted in the replacement of the right winglet of N254WN. The intended destination of the 14 CFR Part 121 scheduled passenger flight was Los Angeles, California. The incident occurred while the airport was operating under visual meteorological conditions. According to the operator, flight #784 was being pushed back from the jetway of gate B-13 when the airplane's right winglet collided with the left winglet of an unoccupied airplane parked at gate B-15. Reportedly, the wing-walker watching the right wing of flight #784 saw that there was going to be contact, and began yelling at the tug driver to stop. In addition to his oral command, the wing-walker also gave the standard visual stop signal of crossing his two batons, but the tug driver did not see or hear either signal. According to the tug driver, prior to the initiation of the pushback, the wheels of the tug were not aligned straight ahead, but were instead turned partially to one side. Therefore as he began the pushback, the nose of the airplane moved toward the jetway instead of going straight back. At that point, instead of terminating the pushback and realigning the tug, the tug driver attempted to maneuver the tug in a manner that would result in the nose of the airplane clearing the jetway. During this attempt, the tug driver's attention became focused upon the jetway, and he therefore did not see or hear the signals given by the wing-walker.