Originally Posted by
ATC Watcher
ATC is normally not monitoring the glide , just azimuth . In addition even if they did , the transponder mode S ALT will need to be detected normally by a rotating SSR antenna, so would take a few seconds to be displayed and another few to transmit the info which would likely be : XXX check or confirm altitude. , GPWS is much faster . It worked well here. Good reaction from the crew, Lesson to be learned ? Oh yes, these cautions warnings on the ATIS to start with More aimed at waiving responsibility from the Airport, authorities than helping the crews. .
In the U.S. they do where TRACON or en route radar is available: MSAW and EMSAW. This was an issue in the KAL 801 747 CFIT at Guam, because ATC had the MSAW disabled.