There is probably a fire in the aircraft. Please arrange for full emergency landing ? the SOS from the pilot of Air Sahara?s Flight 225 from Mumbai to the air traffic control (ATC) of Calcutta airport at 12:15 pm on Wednesday.

The Boeing 737, carrying 116 passengers, finally made a safe but dramatic landing, surrounded by fire tenders, ambulances, tow vehicles and water tenders.

?The pilot sought full emergency treatment. After it landed, the cause of the distress call was traced to a burning smell in the catering cabin beside the cockpit,? airport director V. K. Monga said.

Air Sahara officials in Calcutta, however, refused to comment on the incident.

As the aircraft was approaching Calcutta, crew members detected smoke in the catering cabin. The pilot also spied the smoke inside his cockpit and immediately contacted Calcutta airport ATC.

On receiving the message, ATC officials alerted the Airports Authority of India (AAI). Four crash fire tenders ?specially equipped to handle aircraft fire ? an equal number of ambulances with medical staff, water tenders and tow vehicles rushed to the main runway. ?The fire vehicles were waiting at the pre-determined point of the runway,? the official said.

The flight was scheduled to arrive at the airport at 12.43 pm but it touched down at 12.54 pm. ?The crash fire tenders escorted it to the parking bay, taking no chances with the safety of the passengers,? said an official.

Airport officials said engineers of the private airline set right the defects before the craft flew to Guwahati in the evening.

Sources said Air Sahara schedules were disrupted due to the incident. The Calcutta-Mumbai flight, they added, was delayed by several hours and left after 10 pm.

And the Air Sahara fire-on-flight drama was not the only one played out at the airport on Wednesday. An Air Deccan flight from Calcutta to Guwahati had to return to Netaji Subhas Chandra Bose International airport due to a snag.

The ATR aircraft, carrying 41 passengers, suffered hydraulic leakage and had to return midway, a senior official said. It had left at 10.05 am and returned at 12.41 pm.

Last October, a London-Singapore Qantas Airlines flight had made an emergency landing at Calcutta airport.

The scare had been sparked by a fire alert from one of the engines.