Reazul Bashar and Golam Mujtaba Dhruba bdnews24.com
Published: 2018-03-13 18:41:52 BdST
Transmissions by the Kathmandu tower controller show, despite being cleared to land on runway 02, the US-Bangla Airlines plane began veering off its course, according to JACDEC, a German air safety website.
The captain and the tower controller at Tribhuvan International Airport discussed which runway the aircraft was aiming to touch down on. At one point, the controller told the woman copilot she was heading toward runway 20, although the aircraft had been cleared for runway 02.
Later, the captain took over the conversation and confirmed the plan to land on runway 02. At one stage, ground control said runway 20 had also been cleared for landing.
“Amid much confusion, mostly on the part of the flight crew, the ultimate landing clearance on runway 02 was received,” JACDEC said in its analysis. The crash occurred less than a minute later.
Source: Hamburg-based Jacdec, a news website on air travel safety.
At the time, there was a light tailwind component of six to seven knots.
The 17-year-old Bombardier operated by US-Bangla was following a Boeing 737-800 of Jet Airways (a flight from Mumbai) that landed about three minutes ahead of the Bangladeshi aircraft on runway 02, according to JACDEC.
The crash had left the airport closed for all traffic for two and a half hours.
On Monday, Kathmandu airport officials said they had asked the pilots if they faced a problem after the aircraft changed course in the final descent, but the pilots said they were not, according to a Reuters news agency report.
The plane was then seen circling twice in a northeast direction, Reuters reported citing Raj Kumar Chettri, the airport's general manager. Traffic controllers again asked the pilot if things were OK, and he replied, "Yes".
The tower then told the pilot his alignment was not correct, but received no reply, Chettri added.
US-Bangla, however, defended Captain Abid Sultan, a former pilot of the Bangladesh Air Force, saying he had landed more than 100 times at Kathmandu, where wind shear and bird hits are frequent hazards.
Sultan had more than 5,000 hours of flying under his belt and was specially trained to land at the airport, said airline spokesman Kamrul Islam.
The aircraft was delivered to US-Bangla in 2014, the year it launched flights.
In its four years of flight operations, Monday’s incident is the third aircraft mishap the airline has faced and the second for the Bombardier plane which crashed in Nepal, according JACDEC.
In 2015, the same Dash 8-Q 400 aircraft skidded off from the runway while landing at the Syedpur airport in northern Bangladesh. However, no casualties were reported in the incident involving 74 passengers.
Planes operated by the private airline have recently faced issues like problems in landing gear as well as collapse of one of the engines mid-air.
“They (private airlines) are aggressive in operating flights in a bid to compete with the state-owned (Biman Bangladesh Airlines) . Their priority is flight operations, not aircraft maintenance,” said a Bangladesh aviation industry insider.
“There have been instances where Bangladesh Biman suspended flights due to fog, but some of the private airlines operated,” he told bdnews24.com, preferring anonymity.
US-Bangla;s Kamrul, who have been briefing the media after the crash, did not answer his phone despite several attempts for a comment.
The Civil Aviation Authority of Bangladesh or CAAB, however, says no one is allowed to operate flights beyond the regulations.
“Maintenance records of aircraft are properly documented. No plane is allowed to fly without those records having been checked,” CAAB Chairman M Naim Hassan told bdnews24.com.
The last snippets of the conversations between pilot and the Air Traffic Control or ATC at the airport, which have appeared on the social media, have exposed terrifying moments of confusion over where to land the aircraft.
A Bangladeshi pilot, asking not to be named, has provided an explanation of the conversation to bdnews24.com.
“Most planes approach the runway of the Tribhuvan airport from the south. It’s risky to approach from the north considering external conditions like altitude, air pressure as well as the geographic aspects in Kathmandu,” he said.
According to him, Biman instructs it pilots not to approach the runway in Kathmandu from the north “under any circumstances”.
“We can hear in the conversation that the pilot has been told to approach from the South (runway 02). The pilot also confirmed 02, but he approached from the north.”
He, however, said he has no clue as to how an experienced pilot like Abid Sultan got confused.
The experience of pilot and co-pilot is a major consideration for operating flights in and out of risky airports like Kathmandu’s Tribhuvan.
For instance, Biman pilots are required to log at least 500 flight hours before flying planes to Nepal.
US-Bangla spokesman Kamrul, who said pilot Sultan had 5,000 hours of flying experience, however, did comment on co-pilot Prithula’s flight hours while speaking to the media in Dhaka earlier on Tuesday.
An experienced pilot told bdnews24.com “as far as he knew” it was the first officer’s maiden flight to Kathmandu, an assertion the US-Bangla Airlines denies.
On the pilot and ATC’s conversation, he said, “The co-pilot was in communication with the air traffic, but the pilot later took over. But according to ICAO rules, communications with the tower has to be through the pilot who is not operating the plane for safety reasons.”
Captain Abid Sultan
Abid operated two domestic return flights, which means four takeoffs and as many landings before flying to Kathmandu. The Kathmandu flight was the fifth takeoff and the fifth landing.
“It’s only natural that he was exhausted. That appeared clear from the conversation as well,” the pilot said on the condition of anonymity.
According to him, Biman pilots usually operate the maiden flight of the day with Kathmandu. “If he has flying hours left, he is assigned for another flight. But pilots are never assigned to operate flights after Kathmandu.”
US-Bangla Airlines, however, says Abid was within the daily limit of 11 flight hours on Monday.
“According to the ICAO regulations, a pilot can fly for 11 hours a day. Abid Sultan was way below that limit,” said Kamrul, general manager for the airline’s public relations.
Speaking to reporters on Tuesday, he ducked a question over the pilots’ fitness reports. He also failed to answer when was the last time they had undergone physical fitness tests.