A veteran pilot who once flew the same Air India Dreamliner believes a malfunction in the landing gear may have caused the crash. He didn’t rule out the possibility of power loss and engine failure which led to the tragedy and, along with so many passengers, claimed the life of his close friend, the pilot Sumeet Sabharwal.
“Sumeet Sabharwal was a very good friend. I have flown with him many times. Very nice person, very soft-spoken, very down-to-Earth person. Losing a close friend, losing a beautiful machine, and of course, losing so many passengers is very heartbreaking,” the deceased pilot’s friend Rakesh Rai told a news channel.
Drawing from his extensive experience with the Dreamliner, he pointed to the undercarriage—landing gear that never retracted—as a major red flag. “His (pilot’s) rate of rotation and the way he has climbed up is very normal. But something has gone wrong towards maybe an altitude of 400 to 500 feet. And the momentum has taken the aircraft to about 600 feet. At this point, the most surprising aspect of this take-off is that the undercarriage has not been retracted,” he was quoted as saying.
In normal flight operations, the retraction of the landing gear is a critical early step after take-off. “What happens in a normal take-off is that the moment you start rotating the aircraft for take-off and the aircraft has left the ground, the instruments indicate a positive rate of climb. So, the co-pilot or the pilot monitoring gives a call, ‘positive rate’. The pilot flying cross-checks that there has been a positive rate and he gives a call, ‘gear up’ for the landing gear to be retracted,” he explained. This process, he said, happens typically within 50 to 100 feet of altitude.
“But here, what you see is the undercarriage has not been retracted at all. So that raises a lot of questions as to what could be the reason behind the undercarriage not being retracted. We can only speculate. The actual reason behind that will come out only in the DFDR,” he added, referring to the digital flight data recorder, commonly known as the black box.
Several potential scenarios were put forth by him. One is a bird hit that may have startled both pilots, causing them to miss the gear retraction. However, he acknowledged that this possibility has been largely ruled out by aviation experts. Another theory involves a sudden loss of power, which might have diverted the crew’s attention from standard procedures.
“And the third, very unlikely scenario, is that when the captain says ‘gear up’, the first officer or the co-pilot, instead of raising the gear, retracts the flaps. The retraction of flaps will result in immediate loss of lift. And with the gear down, the thrust will not be able to cope up with the drag being created,” he stated. “The aircraft will not be able to climb.”
He elaborated further on the risks associated with flap retraction during take-off. “In the first scenario we talked about flaps being retracted inadvertently. If the aircraft had sufficient height, maybe a 1,000 feet, the flaps can again be selected and the situation recovered… But the pilots had precisely about 25 seconds.
“Half-a-minute is very less time to react. And that also, one has to keep in mind, it will take about three to four seconds for the pilot to understand what has happened. So that time also you need to reduce from that 25 seconds. It becomes just about 20 seconds. It is extremely difficult to react and recover in 20 seconds in such a situation, one has to understand this. The speed was 170 knots, that’s 320 kmph…”
There’s also the possibility that an engine failure led to an even graver mistake. “Another possibility is that one of the engines failed, and instead of shutting down that engine, the live engine was shut down,” he suggested. “Or in a very rare case, both engines had failed, which was unlikely.”
Asked about whether the aircraft’s safety systems offer any safeguard against improper flap use, Mr Rai was clear: “But for retraction of flaps, there is no such thing. There are only gates… So the movement [of the flap lever] has to be a deliberate movement to cross that gate and go to flaps 1, from say flaps 5. That is the only protection provided.”
Unfortunately, grainy CCTV footage provided no conclusive data on the flap position. “It is impossible to figure out the position of the flaps from the grainy footage of the aircraft before it crashed,” Mr Rai said.
He emphasized that only the official investigation could ultimately determine the cause. “It (mayday call) could have been at the time when the pilot realised whatever wrong happened, has happened. When the aircraft was unable to gain height and it started going down, that is the time the call must have been given… You can see the attitude of the aeroplane increasing because it’s a natural instinct when the ground is rushing towards you, to pull away from it.”
Captain Rai also detailed the rigorous simulator training that commercial pilots undergo. “In the simulator, at least twice a year, all of us are given emergencies. And the simulator is like a real-life thing, called a zero-hour simulator. It means if you can fly this simulator, you can straight sit in the aeroplane and fly it. It is that realistic. We are made to practise different kinds of emergencies,” he said.
On standard procedures in such emergencies, he noted, “Like I told you, the gear-down is the biggest thing in this whole crash. The gear was down and that has most likely created most of the problem. In the simulator, the standard operating procedure is positive rate (of climb) and gear up. It is only after that everything is thrown at us. We are given all kinds of emergencies—engine fire, engine failure, engine severe damage, and we take action accordingly. But training on two engines failing at the same time, I don’t think it’s being done because that possibility is one in millions.”
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