The Air Traffic Control (ATC) radar that helps in tracking aircraft movements crashed at the national capital's Indira Gandhi International Airport on Wednesday evening, disrupting 50-55 flights, an official said.
The ATC was conducting a trial run for a new software platform on which the entire applications of the radar system works. The scheduled trial run was on the new Auto-Trac-III software, which faced similar glitches on July 24.
"A trial run of the new software platform was going on, when at around 5.45 p.m. the screens went blank and the system crashed. Immediately all operations were shifted to the older Auto-Track-II system," an ATC official who did not wish to be named said.
According to ATC sources 50-55 flights were affected, as a backlog of flights had built up which were either waiting to depart or land.
"At least 20 flights were directly affected when the system crashed. After its restoration in 30 minutes, a huge backlog of flights had built up," the official added.
According to an airport official, flights scheduled to depart from 5.45 p.m. to 6.14 p.m. were affected.
"Some departing flights were affected, while the operations at the airport went on smoothly," airport official said.
The Auto-Track-III at Delhi airport was being inducted as the replacement of the older version that had failed on January 14. The Airports Authority of India was advised to review the existing software and applications a the time.