Boeing MAXs face new delay

Federal regulators said flight simulator tests have uncovered a new software problem in the Boeing 737 MAX's software and have directed the aircraft manufacturer to correct it, further delaying the jets' return to commercial service.

While separate from the Maneuvering Characteristics Augmentation System (MCAS) suspected as the cause of two fatal crashes, pilots can use the software in question to correct a malfunction in the anti-stall system, Boeing said in a filing with the US Securities and Exchange Commission.

Correcting the latest problem will not be part of previously planned changes to MCAS. Boeing said a software update should solve the recently discovered problem. If not, a computer chip will be replaced and that could further delay the airplanes' return to commercial service.

"It sounds like this was discovered in a set of conditions not previously modeled or tested," aviation consultant Robert Mann told China Daily. "It could be an overtaxed processor or the manner in which the software code is executed. Until there's a detailed technical explanation, all we can say is the problem didn't show up in previous tests."

The new problem stems from software originally installed in the aircraft, not updates to the MCAS system made after two fatal crashes, the company said.

Boeing, a publicly traded company, is required by law to disclose all matters that could affect its financial performance. In the SEC filing, the company said: "Boeing will not offer the 737 MAX for certification by the (US Federal Aviation Administration) until we have satisfied all requirements for certification of the MAX and its safe return to service."

The FAA said it has no schedule for returning MAX jets to service. It's unclear how long it will take to correct the latest problem.

American Airlines, United Airlines and Southwest Airlines, the three US carriers flying MAX jets, had hoped to return the carriers to service by late August or early September.

On Thursday, Southwest Airlines said it had removed MAX jets from its schedule through October. Southwest has 34 MAX jets, making it the largest US operator of the plane. The airlines will substitute other planes when possible to handle flights of the grounded aircraft and cancel flights as needed.

"We offer our apologies to our customers impacted by this change, and we thank them for their continued patience," Southwest Airlines said in a statement.

Air China, China Eastern Airlines and China Southern also fly MAX jets and the airplanes will remain grounded.

The International Transport Association, a trade group representing about 200 airlines, called on air-safety regulators worldwide to cooperate on returning MAX jets to service and developing common training requirements for pilots. The group said certification by different regulators at different times could confuse passengers.

Boeing MAX jets were grounded worldwide following crashes March 10 in Ethiopia and Oct 29, 2018, in Indonesia that killed a total of 346 passengers and crew. Preliminary investigations suggest the aircraft's MCAS, an automated anti-stall system, apparently forced the noses of Lion Air and Ethiopian Airlines flights down and into a fatal plunge when it erroneously determined the planes were about to stall. To avoid a stall, MCAS points the nose of the plane down to gain air speed.

Meanwhile, Boeing said it is discussing a proposed out-of-court settlement with the families of some of those killed in the Lion Air crash last year.

The discussions were disclosed in a hearing on Thursday in Chicago federal court. Both sides hope to reach an agreement by late August, the Wall Street Journal reported.