KATHMANDU: No airplanes landed at the Tribhuvan International Airport for more than an hour today morning after the VHF Omni-directional radio Range (VOR) and Distance Measuring Equipment (DME) suddenly shut down at 2 am.

However, after necessary maintenance, the flights were allowed to land after nearly six hours.

"As most of the staffs are off-duty at night, we made the equipment function at 8 o'clock in the morning" said Hansha Raj Pandey, head of Communication and Aviation Assistance division at TIA.

"The machine stopped working for sometime. The Gulf Air plane scheduled for landing today morning was delayed for about an hour until we cleared all the obstacles before 8 am in the morning," he informed.

The VOR and DME systems inform the airbus about the landing direction and the distance of the runway. "The information about the breaking down of the system was immediately circulated to all over the international system," Pandey said adding that it was not an abnormal incident though.