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Investigation Reveals The The Fatal Battle Between Ethiopian Pilots And The Boeing 737 Max Autopilot

You all might say we are a bit late to be bringing this to you, but the news and its details have been so tragic that we were unable to write this before. The alarms began ringing only second after Ethiopian Airlines Flight 302 began its journey on March 10 from Addis Ababa with a total of 157 people on board.

The speed and altitude readings of the plane began going cuckoo, a device – stick shaker – activated on the left side of the cockpit. That is the place where the captain of the plane sits. The mechanism makes a powerful sound and rattles the pilot’s control column to give a warning about an imminent aerodynamic stall. However, the Boeing 737 Max was not about to stall. So, what on Earth was going on?

A sensor mounted on Boeing 737 Max was giving false readings to the computer that had activated an anti-stall feature thus forcing the plane into a dive. This is the same system that was also the reason for a crash about five months ago in Indonesia killing 189 persons. The Ethiopian Airlines pilots responded by following some of the steps that Boeing and the US Federal Aviation Administration had recommended in the light of the first accident. However, they did make a critical oversight; the engines were left to almost maximum.

Roger Cox, a former accident investigator at the National Transportation Safety Board, said, ‘The thrust was a full bore the whole way. That is extremely curious.’ Roger has also flown the earlier models of the 737 while working as an airline pilot. On the other hand, Ethiopian Transport Minister Dagmawit Moges stated in a press conference that the pilots had followed the proper procedure that was issued after the crash in October of a Lion Air jet and suggested that Boeing should review the flight-control system. Ethiopian Airlines Group is rethinking its decision of purchasing another 25 additional 737 Max from Boeing.

Boeing is under a lot of pressure as of now since the 737 Max 8 has been grounded. Boeing is reportedly working into an update that will fix the issue. However, things are not looking great for Boeing as whistleblowers are coming forward with different things to tell and investigations are being opened up. Boeing CEO Dennis Muilenburg said, ‘We at Boeing are sorry for the lives lost in the recent 737 Max accidents.’ He has blamed the accident on a ‘chain of events’ but did acknowledge the malfunction of the sensor.

It also made it difficult to control the plane because of its near-maximum thrust. This led to creating even more problems along with the flaw in the 737 Max’s software as per the pilots that have reviewed the preliminary report issued by Ethiopia’s Aircraft Accident Investigation Bureau. Jeffrey Guzzetti, the former director of the FAA’s Accident Investigation Division, said, ‘They exacerbated it.’

The pilots did take some of the steps that were recommended by Boeing and the FAA for counteracting the MCAS. However, they were confused and eventually lost control. Muilenburg said, ‘As pilots have told us, erroneous activation of the MCAS function can add to what is already a high workload environment. It’s our responsibility to eliminate this risk. We own it, and we know how to do it.’ Dennis Tajer, a spokesman for the Allied Pilots Association at American Airlines, said, ‘Everyone can talk about it from a desk, but when you see it happening it’s another thing. What steps were taken, what steps were missed? Those are all things we’re going to be looking at for several weeks.’

Pilots have somewhat divided on whose fault it is; some are saying that the Ethiopian Airlines pilots were unable to follow the procedures properly while others are saying that the pilots’ line of action is justified given the level of chaos during the situation. However, all of them agree that the speed was in fact critical. The plane took off at 94% of full power – a normal norm for planes taking off – however, It didn’t move to its speed of 274 miles per hour that was called by the captain even after a minute of take-off.

It sped to 420 mph during its final dive, about twice the conventional top speed for such a low altitude. The pilots had not only the MCAS failure warnings but also audible alerts stating that the plane had exceeded the safe flying speed. The crew did follow one important step that was designed for dealing with an MCAS failure; shutting off power to the motor that the system uses for automatically driving down the nose. However, adjusting the pitch manually became quite difficult because of the speed of the plane.

The crew tried control column to continue flying while applying strong pressure with the trim system powered off. This continued for over two minutes. The captain asked the co-pilot to try and make adjustments – called trimming – manually. According to the report, the first officer replied that it was not working. At the speed that the plane was flying at, turning the two wheels by hand to trim would have been ‘very hard to more or impossible’ as per John Cox.

They eventually switched the power back on for the trim system about 30 seconds before the plane crashed. It slightly raised the nose before MCAS engaged again – about five seconds after turning the power on – and pushed the nose of the plane down again. They were unable to recover by relying on control column alone, and the plane pointed down by 40 degrees and attained a speed of 575 miles per hour.

Tajer said, ‘You can’t read the transcript and not put yourself in the cockpit. Every honest pilot says, I could see me right there, doing that, even if it was not a good thing, or saying, yeah that makes sense.’