Why audio of Air India flight pilots increases mystery about the accident

Report points out that switches that turn off fuel were triggered seconds after takeoff in Air India accident. See the moment when plane with more than 240 people on board crashed in India investigators made a frightening discovery in the preliminary investigation into the Air India Flight 171 accident, which killed 260 people in June. A few seconds after takeoff, the two 12-year-old Boeing 787 Dreamline fuel control switches moved abruptly to the Cut-off position (or off), depriving fuel engines and causing total power loss. ✈️ The Cut-off activation movement is usually performed only after landing. The driver’s voice recording in the cabin records one asking the other why he had turned off fuel supply. The other answers that he had not done. The recording does not clarify who said what. At the time of takeoff, the co -pilot piloted the aircraft while the captain monitored. The switches were then placed back to their normal position, which would lead to the engine restarting process. At the time of the accident, one engine was recovering the power, while the other had been reactivated, but had not yet recovered the power. Air India flight 171 remained in the air for less than 40 seconds before falling into a busy neighborhood in the city of Ahmedabad, western India, marking one of India’s main air disasters. Researchers are examining the wreckage and recorders of the cabin to understand what went wrong right after takeoff. The Air India flight rose at 190 meters in clear time before losing location data after 50 seconds, according to FlightTar24. Reuters Flight 171 of Air India remained in the air for less than 40 seconds before falling into a busy neighborhood in the city of Ahmedabad in western India the 15 -page report released this week offered preliminary information. The investigation – led by Indian authorities with Boeing experts, General Electric, Air India, Indian regulatory agencies and US and UK participants – raises several issues. Investigators say that lever lock fuel switches are designed to avoid accidental activation – they should be pulled up to unlock before they are triggered, a safety feature that goes back to the 1950s. Constructed according to rigorous standards, they are considered highly reliable. Protection Supports protect them even more from accidental impacts. “It would be almost impossible to trigger the two switches with a single hand movement, which makes an accidental activation unlikely,” the BBC told Canada -based air accidents, which he declined to be identified. This makes the case of Air India stand out. Whether one of the pilots was responsible for turning off the switches, intentionally or not, “raises the question: why … Turning off the switches,” said Shawn Prchnicki, a former aircraft plaster and aviation expert at Ohio State University in the United States. “Was it intentional or the result of confusion? It seems unlikely, as pilots did not report anything abnormal. In many emergencies in the cabin, pilots can press the wrong buttons or make incorrect selections – but there was no indication of such a situation here, nor any discussion suggesting that fuel switches were selected by mistake. This type of error usually does not happen without any evident problem,” he told BBC. Peter Goelz, a former administrative director of the US National Transport Security Council (NTSB), has a similar assessment: “The discovery is very disturbing: a pilot turned off the fuel switch seconds after the flight.” “There is probably a lot more information on the cabin’s voice recorder than what was shared. A single sentence like ‘why you turned off the switches’ is not enough,” he said. “The new details suggest that someone in the command booth turned off these valves. The question is: who and why? Both switches were turned off and restarted in seconds. The voice recorder will reveal more: it was the flight pilot that was trying to reconnect the engines or what was monitoring?” Researchers believe that the control booth recorder-with audio of pilots microphones, called radio and sounds of the cabin environment-contains the key to this puzzle. “They have not yet identified the voices, which is crucial. Usually, when the voice recorder is revised, people familiar with the pilots are present to help compare the voices. So far, we still don’t know which pilot has turned off and turned on the switches,” Goelz said. In short, investigators say that what is needed is a clear identification of the voice, a complete transcript of the cabin with identified speakers and a complete review of all communications from the moment the plane left the boarding gate until the crash. They also claim that this reinforces the need for video recorders in the cabin, as recommended by NTSB. An image with vision over the shoulder would show which hand was on the fuel -cut switch. Before boarding flight 171, both the pilots and the crew went through the breathalyzer tests and were released to fly, the report says. The pilots, based on Mumbai, arrived in Ahmedabad the day before the flight and had proper rest. But researchers are also focusing on what they describe as an interesting point in the report. The report states that in December 2018, the US Federal Aviation Administration issued a Special Aeronavability Information Bulletin (SAIB) highlighting that some Boeing 737 fuel control switches were installed with the disgusting feature. Although the problem has been observed, it was not considered an insecure condition that required an aircraft guideline (DA) – a legally applicable regulation to correct unsafe conditions in a product. The same switch project is used at Boeing 787-8 aircraft, including Air India’s VT-ANB, which has fallen. As the SAIB Bulletin was advisory, Air India did not perform the recommended inspections. Prchnicki said he is wondering if there was a problem with fuel control switches. “What this [parte do relatório] Does it mean exactly? Does it mean that with a single touch, could this switch turn off the engine and cut the fuel supply? When the locking feature is disheveled, what exactly happens? Could the switch simply turn off and turn off the engine? If that’s the case, it’s a really serious problem. If not, this also needs to be explained, “he said. Others, however, are not convinced that this is a fundamental problem.” I have not heard of it, which seems to be a discreet question of FAA [Administração Federal de Aviação dos EUA]. I didn’t hear any complaints either [sobre os interruptores de combustível] of pilots – who are usually quick to speak up. It is worth analyzing, as it was mentioned, but it may only be a distraction, “said Goelz. Captain Kishore Chinta, a former India Aeronautical Accident Investigation Department (AAIB), wonders whether the switches fired due to a problem in the aircraft’s electronic control unit.” move? If fuel cutting switches have fired electronically, it is a matter of concern, “he told the BBC. The report states that fuel samples from refueling tanks were” satisfactory. While waiting for further investigation. The report also stated that the aircraft’s ram Air turbine was called – a clear sign of a severe failure in the systems – and that the landing train was found in a “lowered” or not collected position. They record critically low pressure, providing limited energy to maintain essential operational flight systems. “The activation of RAM Air Turbine (RAT) strongly corroborates the conclusion that both engines have failed,” said Prchnicki. Retraction of the landing train. When the landing train lever is pulled, we are already about 60.9 m (200 feet), and the entire landing train retraction process is completed at about 120 m – about eight seconds in total, thanks to the aircraft high pressure hydraulic system. Scare – You are appalled. At that moment, the landing train is not its focus. Your mind is focused on one thing: the flight trajectory. Where can I land this aircraft safely? And in this case, there was simply not enough altitude to work. “The investigators say the crew tried to recover, but it happened too fast.” The engines were turned off and then turned on. The riders realized that the engines were losing thrust – probably restarting the left first, followed by the right, “said Prchnicki.” But the right engine didn’t have enough time to accelerate again, and the thrust was insufficient. Both were eventually configured to “work”, but with the left off first and the right too late to recover, it was simply too late. ”

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