All the people in the Kathmandu-bound flight, however, are safe, airport sources said.
"The Royal Nepal Airlines flight number RA-218 which took off for Kathmandu from here at about 20:00 hours, sought an emergency landing permission as a wing flap failed to open. The aircraft had 160 people on board," the sources said.
The plane safely landed on runway 28 of IGI airport within 20 minutes of the take off, they said.