I was around 16 or 17 yrs old with several friends and we seen a boomarang shape object circle in the ski. We all say did you see that. "I saw it, so what did you see." Confirmed image of what I saw threw 5 others. Started talking about what we saw and it appeared again as a boomarang circleing the ski and form into a triangle and dissappeared. I suppose the triangle shape was from the back of the aircraft accelerating away. This instance was over 12 years ago and there are several wittnesses.