Boeing carried out the final test of its 737 MAX with the modified MCAS anti-stall system on April 18, 2018. The manufacturer is now awaiting for a new flight certification from the United States Federal Aviation Administration (FAA).

Test pilots have completed “120 737 MAX flights totaling more than 203 hours of air time” with the updated MCAS system, according to Boeing CEO Dennis Muilenburg who posted a video on Twitter. He added that “more than 85 percent of the world’s more than 50 operators of 737-Max machines have now had the opportunity to see the MCAS-Update on the flight simulator in action.”

We’re making steady progress on the path to certification for our 737 MAX software update thanks to the work of our Boeing pilots, engineers and technical experts. pic.twitter.com/DIHrhG2OOi

— Dennis A. Muilenburg (@BoeingCEO) April 18, 2019

Following the crashes of Lion Air in October 2018, and Ethiopian Airlines in March 2019, the global fleet of Boeing 737 MAX has been grounded. The two main operators of the aircraft, Southwest Airlines (LUV) (34 planes) and American Airlines (A1G) (AAL) (24) have to cancel an average of 275 daily flights, and should do so until August 2019.