(http://www.tulsaworld.com/images/2006/060703_A1_Plane1516_a1plane.jpg)
The best I can gather from various news reports is that grandpa and grandson took off from a private field, landed on a residential road, drove around clipping a street sign, then took off from the road into power lines.
Did the pilot just lose his mind?
http://www.tulsaworld.com/NewsStory.asp?ID=060703_Ne_A1_Plane1516
http://www.kten.com/Global/story.asp?S=5106192