NTSB chairman Mark Rosenker was busy stumping about issues related to GA safety last month. He spoke to a group of airport executives and FAA representatives at an airport technology seminar about the importance of runway incursion safety. He stressed that while aircraft separations in the air are based upon miles, on the ground space is measured in feet. Rosenker also noted that many recent incursions have been avoided “through flight crew actions sometimes bordering on the heroic, along with a lot of luck.” The chairman emphasized that technology unique to the size of the airport in question is essential to reducing the number of accidents and incidents.