It was the longest 10 minutes for the air traffic control at the Delhi airport.
On Tuesday morning, the air traffic control (ATC) tower at the airport went into a tizzy after the radar system developed a snag.
For 10 very tense minutes, the Delhi ATC had no data about flights landing at or flying out of the Indira Gandhi International (IGI) Airport.
Due to the snag, the Flight Data Processing System (FDPS) stopped working between 11.25am and 11.35am.
"The input that is received from the radar are actually signals and this raw data is processed and converted by the FDPS," said a senior ATC official who did not wish to be named.
"Thanks to FDPS, we get all data and coordinates of each flight, like its speed, height and flight code," he said.
As the system suddenly stopped working, panic ensued at the ATC tower, sources said. "Everyone was tense as we had to revert to a more manual procedure and all airborne pilots were asked to slow down to avoid any mishap," he said.
"The FDPS is the heart of air traffic management and you can say what it had this morning was a mild attack."
This is not the first that time that the radar system at Delhi ATC has faced a snag.
There were at least six serious and minor technical snags that the system faced last year.The worst was on January 14, 2010, when the entire radar system collapsed and air traffic controllers had to manage traffic manually for nearly an hour.
There were more such separate incidents after this, when, one or more radar screens, if not the whole system, have gone blank.
"We are handling close to 750 flights at IGI Airport every day and definitely need a more reliable system," the official said.
The Airports Authority of India (AAI), which manages all civil air traffic in the country, admitted that there was a snag in the FDPS.
However, it tried to play down the incident.
"There was a problem in one of the systems for a brief period but we had a backup ready and there were no flight delays due to this," an AAI spokesman said.
"We have a redundancy plan in place and there was no reason to worry vis-à-vis what happened today."