The FAA recently added new Safety Logic runway incursion alerting technology to its ASDE-X airport surveillance equipment at Orlando International Airport in Florida. ASDE-X combines radar scanning with a transponder tracking system to provide controllers with a real-time picture of airborne and airport surface traffic. Safety Logic, developed by ASDE-X builder Sensis, monitors approach and surface movements and provides controllers with visual and aural caution and warning alerts, including aircraft callsigns, upon detecting any of 32 different incursion scenarios. After Orlando, all ASDE-X systems will be retrofitted with Safety Logic. Sensis also builds airport vehicle transponders, which may be introduced later. Safety Logic is expected eventually to replace the Airport Movement Area Safety System (AMASS), an earlier non-transponder-based system that has been criticized due to interpretation difficulties that occasionally led to last-minute resolution of runway incursions.