In Northern Armstrong County:  One person, a pedestrian, was killed when struck by a truck tractor.     State Police identify the deceased as 47-year-old Gordon Thomas Solley Junior of the Templeton area.     Solley was a pedestrian who was trying to cross Routes 28-and-66, north of the junction with Route 85, in Rayburn Township, about Ten Tuesday night.     Solley ran across the highway and into the path of the vehicle which was driven by Kevin Raible of Gibsonia.     The truck driver was unable to avoid hitting the pedestrian.     Solley was pronounced dead at the scene.