boeing now says it has completed a software fix for its grounded 737 max jets, but the update will have to win approval from u.s. and international regulators before the planes can return to fly. the system played a role in the crash of two jets operated one by lion air in october, another by ethiopian airlines in march. 346 people died in those crashes. in both accidents the anti-stall system pushed the plane's noses down while the pilots struggled to retain -- regain control. joining me now is former faa safety inspector and cnn safety analyst david susie. david, looking at this now, these were multiple failures by boeing throughout this, both before the first crash, after the first crash, before the second crash. i just wonder how can flyers be confident that the fix boeing says it has now makes these planes safe to fly?