Boeing will roll out an upgrade to the software in the MCAS stall prevention system on the 737 MAX aircraft that have had two deadly accidents in recent months, an industry source told AFP. 


The system was implicated in the crash of a 737 MAX 8 in Indonesia in October but the source cautioned that the cause of the fatal Ethiopia Airlines accident last weekend has not yet been determined. 


The fix will only take about two hours to install, the source said. 


The MAX aircraft have been grounded worldwide.Boeing said it supports the grounding of its planes as a precautionary step, while reiterating its "full confidence" in the safety of the 737 Max. 


The software fix for Boeing’s 737 Max models may end up costing the Chicago-based aircraft manufacturer billions of dollars as it redesigns a computerised flight-control system on hundreds of jets sitting idle around the world.


The fixes alone for the revamped version of Boeing’s single-aisle workhorse 737 could cost the company around $500 million if everything is resolved in six to eight weeks, according to Canaccord Genuity analyst Ken Herbert.

Delivery delays and reimbursements to airlines for flight disruptions would add another $2 billion in lost cash flow each month the planes are kept on the ground by regulators, Herbert said. Boeing could make much of that money back if deliveries resume promptly.


The Max jets are likely to be idle for weeks while Boeing tries to assure regulators around the world that the planes are safe. How long the planes stay grounded depends largely on what investigators find on the cockpit voice and flight data recorders, said Peter Goelz, a former managing director for the National Transportation Safety Board. 


At a minimum, aviation experts say, the plane maker will need to finish updating software that might have played a role in the Lion Air crash. 


If  the recorders indicate a manufacturing problem or a software glitch in the anti-stall system, the planes could stay on the tarmac for a long time. But if the crash was caused by pilot error, then the problem could be corrected by training, and the grounding could be short, Goelz said. .. 


Ethiopian Airlines says its pilots received special training on how to deal with the Max's anti-stall software. 


The company has previously characterised the software upgrades as an effort to make a safe plane even safer. Engineers are making changes to the system designed to prevent an aerodynamic stall if sensors detect that the jet's nose is pointed too high and its speed is too slow. Satellite-based data showed that both the Ethiopian Airlines and Lion Air planes flew with erratic altitude changes that could indicate the pilots struggled to control the aircraft. Both crews tried to return to t .. 


Aviation regulators worldwide laid down a stark challenge for Boeing to prove that its grounded 737 Max jets are safe to fly amid suspicions that faulty software might have contributed to two crashes that killed 346 people in less than six months 


Regulators will wait for more definitive evidence of what caused both crashes. Some industry officials think the plane maker and US regulators may be forced to answer questions about the plane's design. 

In a key step toward unearthing the cause of the Ethiopian Airlines crash, flight recorders from the shattered plane arrived Thursday in France for analysis, although the agency in charge of the review said it was unclear whether the data could be retrieved. 


The decision to send the recorders to France was seen as a rebuke to the United States, which held out longer than most other countries in grounding the jets. 

Boeing executives announced that they had paused delivery of the Max, although the company planned to continue building the jets while it weighs the effect of the grounding on production. 


In Addis Ababa, angry relatives of the 157 people who were killed Sunday stormed out of a meeting with airline officials, complaining that they were not getting enough information. 

The US Federal Aviation Administration grounded the planes Wednesday, saying regulators had new satellite evidence that showed the movements of Ethiopian Airlines Flight 302 were similar to those of Lion Air Flight 610. 


That flight crashed into the Java Sea off Indonesia in October, killing 189 people.