The chaotic aftermath of Saturday’s Great Earthquake saw TIA straining to handle rescue and humanitarian aid flights from different countries, including charters to rescue foreign nationals. An estimated 30,000 tourists, mostly Indians, have left the country in the last five days.

The largest aircraft to land at the TIA were a Boeing 747-400 from Israel, an Airbus A350 from France and a heavy military transport aircraft, the Ilyushin Il-76, from India. The 747 is often referred to by its nickname, the Jumbo Jet or the Queen of the Skies. An A350 landed at the TIA for the first time on Wednesday.

TIA officials said that the airport handled 188 flight movements for domestic carriers, 88 scheduled international flights, 49 charters flights of humanitarian aid, 41 search and rescue flights of the Indian Air Force, with the rest from Nepali helicopter operators.  

TIA witnessed severe air traffic congestion due to the increased movement of larger jets, placing air traffic controllers under increased pressure. Due to limited parking bays, a number of aircraft have been parked on the taxiway.

According to India’s foreign ministry, 13 military aircraft and three civilian aircraft from Air India and Jet Airways have been mobilised to help with rescue operations. On Wednesday, China and Russia sent five and three planes, respectively, for rescue and humanitarian aid. Similarly, two aircraft from the United Arab Emirates, and one each from Canada, France, Bangladesh, Thailand, Switzerland, Pakistan and a minister-led team from Sri Lanka landed in Kathmandu on Wednesday.

TIA statistics showed that there were 393 flight movements on Tuesday. Due to the deadly earthquake, the airport saw the lowest flight movements—170—on Saturday.

Managing the dramatic increase in air traffic was made all the more difficult due to repeated aftershocks that continued to shake the control tower. However, controllers managed to take decisions and issue instructions, said an air traffic controller, who did not wish to be named.

“The traffic controller’s decision has to be right every time and every second, we were focused on aircraft safety and the separation of aircraft to avoid collisions,” the air traffic controller said.  

Another air traffic controller said that some aircraft were told to circle the skies for upto two hours. “In the last four days, many aircraft were forced to divert fearing that they could run out of fuel,” he said. Sanjiv Gautam, deputy director general of the Civil Aviation Authority of Nepal, said that TIA was forced to hold many planes in the skies and a few others were diverted due to safety issues. “Despite all odds, TIA managed to ensure smooth operations,” said Gautam.

There are, however, worries that such large aircraft could damage the runway at the country’s sole international airport, especially in the pre-monsoon season. A report submitted nearly a year ago by Ayesa Ingenieria of Spain, which had been contracted to evaluate TIA’s runway and taxiway, had revealed that the TIA runway is not capable of handling wide-body aircraft due to its ageing asphalt foundation. The runway’s upper surface comes instantly under stress when heavy jets land.

The report also said between 2006 and 2013, when compared to the core part of the runway, damage to the intermediate layers was caused by the operation of large jets like the Airbus A330 and the Boeing 777. In 2013, there were a thousand operations of A330-300 aircraft, 955 Boeing 777s and 452 A330-200s. These numbers are expected to double in the next 20 years.

Frequent cracks on the runway have been affecting smooth operations at TIA since 2011.