Dhaka, Bangladesh
Kathmandu plane crash cause yet to be known

Kathmandu plane crash cause yet to be known

Experts say an audio recording of the last minutes of conversation between the pilots of the crashed plane in Nepal and the air traffic control shows signs of miscommunication, reports BBC. The plane carrying 71 passengers and crew crashed on landing at Nepal's Kathmandu airport on Monday, killing 49 people. Flight BS211, operated by Bangladeshi airline US-Bangla, veered off the runway while landing. The exact cause of the crash remains unclear and an investigation has been launched. However, the recording suggests there could have been a misunderstanding over which end of the sole runway the plane was cleared to land on. Captain Pawandeep Singh, a pilot with an Indian airlines, told the BBC that the recording showed that there was confusion in the cockpit. "I am not sure what specifically happened in this case, but it seems like there was miscommunication while the pilot was trying to land the plane. But we will know the complete truth only when investigators file their report," he said. Singh added that "it seemed the pilot was trying visual landing". "Usually, pilots use Instrument Landing Systems (ILS) to land aircraft, but in some scenarios they are allowed visual [manual] landing too where the runway is in pilot's vision. But such landings can be tricky in airports like Kathmandu," he said. Aviation expert Greg Waldron said "unclear communications have been the cause of past crashes" as well. "This is true of both ground to air communications, as well as crew communications in the cockpit. While the exact cause of this crash has yet to be determined, the Air Traffic Control (ATC) recordings suggest the crew was possibly disoriented and out of their comfort zone. This is a bad situation when coming in for a landing," he said. Singh, however, added that the language used in communications between pilots and ATCs is standardised around the world. "We rarely face problems while communicating with ATCs anywhere in the world. And pilots always have to repeat the instructions, which leaves little room for confusion. Miscommunication can only happen with numbers - in this case the confusion seems to be between numbers 02 and 20 - which are markings on each end of the runway," he said. Waldron also said that the numbers can be confusing. "Confusion unfortunately does happen, and pilots note that sometimes 02 and 20 can sound too similar over the radio. That said, the ground controllers appeared to give contradictory instructions prior to the aircraft's approach, switching from 02 to 20," he said. Singh said another factor could have been the location of the airport in Kathmandu. "Kathmandu is not the easiest airport to land because you have to navigate through mountains. Pilots have to go through special training to fly to Nepal. I have flown there and can tell you that's it's a busy airport," he said. Basil Moses, a senior commander with Air India, further explained why landing at Kathmandu airport is considered difficult. "Two sides of the airport are surrounded by mountains. There is a gap between the mountains to enter and exit. It's tricky for all pilots. It gets worse during nights and monsoons. Having said that, the weather was fine when the Bangla-US plane came in," he said. "I say again, turn!" the air traffic controller called over the radio, his voice rising, as the flight from Bangladesh swerved low over the runway at Kathmandu's small airport. Seconds later, the plane crashed into a field beside the runway, erupting in flames and leaving 49 of the 71 people on board dead. That moment Monday appeared to result from minutes of confused chatter between the control tower and the pilot of the US-Bangla passenger plane, as they discussed which direction the pilot should use to land safely at the airport's single runway. A separate radio conversation between the tower and at least one Nepali pilot reflected the sense of miscommunication. "They appear to be extremely disoriented," a man said in Nepali, watching as Flight BS211 made its approach, though it was not clear if the voice belonged to a pilot or the tower. "Looks like they are really confused," said another man. In the recording, posted by air traffic monitoring website liveatc.net, the pilot and the tower shifted back and forth about whether the pilot should approach the runway from the north or the south. Moments later, the controller came back on the air, his voice clearly anxious, and told the pilot, "I say again, turn!" Seconds after that, the controller ordered firetrucks onto the runway. Kathmandu officials and the airline laid the blame for the accident on each other. The airport's general manager told reporters Monday that the pilot did not follow the control tower's instructions and approached the runway from the wrong direction. "The airplane was not properly aligned with the runway. The tower repeatedly asked if the pilot was OK and the reply was 'Yes,'" said the general manager, Raj Kumar Chetri. But Imran Asif, CEO of US-Bangla Airlines, told reporters in Dhaka that "we cannot claim this definitely at the moment, but we are suspecting that the Kathmandu air traffic control tower might have misled our pilots to land on the wrong runway." After hearing the recording between the tower and the pilots, "we assumed that there was no negligence by our pilots," he said. Prior to the crash, the plane circled Tribhuvan International Airport twice as it waited for clearance to land, Mohammed Selim, the airline's manager in Kathmandu, told Dhaka-based Somoy TV.

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