Boeing’s (BA) 737 Max was cleared to fly too early, according to the company’s former senior manager Ed Pierson.
The aircraft was grounded worldwide for 20 months following two fatal crashes in Indonesia and Ethiopia that killed 346 people. However, US safety regulators cleared the plane to fly again in North America and Brazil in November last year.
The Federal Aviation Administration (FAA) said existing planes would need to be modified before going back into service, with changes to their design, while pilots would need retraining. It said the design changes it had required had "eliminated what caused these particular accidents.”
The plane is also set to get the green light in Europe after the head of Europe's aviation safety agency, EASA, confirmed it will get final clearance to resume flying this week.
However Pierson, who retired from Boeing in August 2018, claims in a new report that investigators have overlooked factors he believes may have played a direct role in the incidents.
Investigators believe the accidents were triggered by the failure of a single sensor, specifically the MCAS software, as well as the regulatory oversight failures of the FAA, and the lack of training provided to pilots.
“Although each of these problems played major roles in both accidents, they were not the triggering events,” Pierson said.
He claims that intermittent flight control system issues and electrical anomalies played a part as they occurred in the days and weeks before the accidents.
These may have been symptoms of flaws in the aircrafts' highly complex wiring systems, which could have contributed to the erroneous deployment of MCAS, he said.
Pierson also highlights that sensor failures contributed to both accidents and questions why such failures were happening on brand new machines.
He believes that deeper investigation of electrical issues and production quality problems at the 737 factory in Renton, near Seattle, is required.
Pierson testified as a whistleblower before US Congress in December 2019 regarding the 737 Max.
In an email to the 737 general manager a year earlier, Pierson said: “Frankly right now all my internal warning bells are going off. And for the first time in my life, I’m sorry to say that I’m hesitant about putting my family on a Boeing airplane.”
Lion Air flight JT610 crashed off Indonesia in October 2018. Five months later, Ethiopian Airlines flight ET302 crashed minutes after take-off from Addis Ababa.
On the weekend, Boeing announced it will begin to deliver commercial airplanes capable of flying on 100% biofuel, or sustainable aviation fuel, by 2030.
The aviation giant said that reducing environmental damage from fossil fuels was the “challenge of our lifetime.”
The International Air Transport Association (IATA) plans to cut carbon emissions to half of 2005 levels by 2050, meaning Boeing’s biofuel target is 2030, as jetliners typically are in service for around 20 years.
While the planemaker has about 10 years to reach its goal, it is not the first time the company used biofuel. In 2018, Boeing successfully flew the world’s first commercial flight using 100% biofuel.
Yahoo Finance has reached out to Boeing for comment.
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