Boeing must perform more work on its proposed fix to 737 MAX aircraft before it can be submitted for review, US officials said on Monday, suggesting the planes could stay grounded a while longer. Additional work is needed “to ensure that Boeing has identified and appropriately addressed all pertinent issues,” a Federal Aviation Administration spokesman said in a statement.
Boeing has issued changes to controversial control systems linked to two fatal crashes of its 737 Max planes in the last five months. But it's still not certain when the planes, that were grounded worldwide this month, will be allowed to fly. Investigators have not yet determined the cause of the accidents.