eligible air traffic system or equipment
(3) Definition .— In this subsection, the term “eligible air traffic system or equipment” means— (A) an instrument landing system consisting of a glide slope and localizer (if the Administrator has determined that a satellite navigation system cannot provide a suitable approach to an airport); (B) an Automated Weather Observing System weather observation system; (C) a Remote Communication Air/Ground and Remote Communication Outlet communications facility; or (D) a Medium Intensity Approach Lighting System with Runway Alignment Indicator Lights.