Late last month, the primary radio frequency on which the new Air Traffic Control (ATC) tower at Mumbai airport communicate with pilots went down mysteriously and came back alive equally mysteriously after 24 hours. No one knows the exact reasons for the failure even now, though some officials say that the role of amateur hackers cannot be ruled out.While ATC officials immediately shifted to a backup frequency, they were without a primary frequency for an entire day. Had the backup frequencies too have malfunctioned, the situation would have been catastrophic. The airport sees more than 800 flight landings and take-offs every day.<!– /11440465/Dna_Article_Middle_300x250_BTF –>Airport insiders claim that it is difficult for a radio frequency to get compromised. But the incident raises the possibility of amateur hackers crawling their way into ATC radio transmission. Once the transgression was noticed, officials from the Communication, Navigation and Surveillance (CNS) wing, responsible for ATC infrastructure maintenance, first checked at their end. When they found that everything’s fine on their side, they contacted many airlines like Jet Airways, Reliance and Air Works, whose hangars span across a large area. In fact, CNS officials said they asked Air India officials to check if their aircraft communication devices were working properly as the national carrier’s hangar was nearby. But Air India never replied to CNS and when dna asked about the incident, the airline’s spokesperson refused to comment. Officials of Mumbai International Airport Ltd (MIAL) also refused to comment. CNS officials blamed staff shortage for the incident. And if what some officials told dna is to be believed, this was not an isolated incident. “Incidents like these are increasingly becoming the norm,” they said.For example, last month itself, a radar at the Juhu airport developed a snag. While CNS officials were attending to it, there erupted another problem within an hour. This time, a radar at the Mumbai airport started malfunctioning. Consequently, half the staff had to rush back. “This led to the division of already scarce staff, thereby delaying the rectification of both the radars,” said a CNS official.A complaint on the primary frequency malfunctioning has been lodged with the Wireless Planning and Co-ordination (WPC) wing of the ministry of communications. The WPC looks at complaints of harmful interference in the reception of radio emissions and hold investigations. VV Singh, joint wireless advisor at Mumbai WPC, could not be contacted for comments.Though the CNS requires a staff of 260, it has to make do with 140 now.“There are barely 4-5 staffers working during a shift, as a result of which equipment and radars cannot be maintained properly. If some malfunctioning is reported, corrective actions are taken,” said a CNS official.For passengers and crew in 800 flights that fly into and out of the airport every day, that’s cold comfort.