Abstract: A method and computer program using airport surveillance data to define common paths taken by vehicles on the airport surface is presented. Position data points for a group of vehicles create separate paths for each of the vehicles in the group. A matrix is created including areas measured between the path of each vehicle in the group and each of the remaining vehicles in the group. A column-wise average for each of the columns in the matrix is calculated, the column having a lowest mean average of all of the columns is determined, and a vector A(J) including the areas and vehicle identifications is created from that column. A difference vector ?A(J) is created having the difference between successive entries in the vector A(J), and subgroups with the group are recursively identified using the values in the difference vector.