Boeing is making “steady progress” towards getting the 737 Max aircraft ready to re-enter service following two fatal crashes.

The message came from chief executive Dennis Muilenburg, addressing the company’s annual meeting.

The 737 Max remains grounded worldwide after an Ethiopian Airlines flight crashed near Addis Ababa in March, killing all 157 people on board.

It followed Lion Air 737 Max disaster in Indonesia five months earlier, which claimed 189 lives.

Boeing has been “working tirelessly” to finalise and implement a software update “that will ensure accidents like these never happen again,” Muilenburg told shareholders.

“The update will prevent erroneous angle of attack sensor readings from triggering the Manoeuvering Characteristics Augmentation System, or MCAS, something that initial investigation reports indicate occurred in both MAX accidents, as one link in a longer chain of events,” he said.

“We know we can break this link in the chain. It’s our responsibility to eliminate this risk.

“We’re making steady progress on the path to certification, having completed the official engineering test flight of the software – the final technical flight test prior to the certification flight.”

Muilenburg revealed that test pilots have made 146 737 Max flights totalling 246 hours of air time with the updated software.

Nearly 90% of 50-plus Max operators around the globe have experienced the software update themselves during one of the manufacturer’s simulator sessions.

“With the certified software update implemented, the 737 Max will be one of the safest airplanes ever to fly,” Muilenburg insisted.

“There is nothing more important to us than the safety of our airline customers and their passengers. Every day, 5.3 million people fly safely on Boeing airplanes. In addition, more than 2,900 737 airplanes on average are in the air with nearly half a million people on board at any given time, and one 737 takes off or lands around the world every one-and-a-half seconds.

“We don’t make safety features optional. Safety has been and always will be our top priority, and every one of our airplanes includes all of the safety features necessary for safe flight.”

However, It emerged that Boeing did not activate a “disagree alert” feature on the 737 Max 8 that warned pilots if the sensor was transmitting faulty data about position of the aircraft’s nose.

In response, the company said: “Boeing included the disagree alert as a standard feature on the Max, although this alert has not been considered a safety feature on airplanes and is not necessary for the safe operation of the airplane.

“Boeing did not intentionally or otherwise deactivate the disagree alert on its Max airplanes.

“As the Max safely returns to the air after the software modifications are approved and certified, all Max production aircraft will have an activated and operable disagree alert and an optional angle of attack indicator.

“All customers with previously delivered Max airplanes will have the ability to activate the disagree alert per a service bulletin to airlines.”

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