Boeing has long embraced the power of redundancy to protect its jets and their passengers from a range of potential disruptions, from electrical faults to lightning strikes. The company typically uses two or even three separate components as fail-safes for crucial tasks to reduce the possibility of a disastrous failure. Its most advanced planes, for instance, have three flight computers that function independently, with each computer containing three different processors manufactured by different companies. So even some of the people who have worked on Boeing's new 737 MAX airplane were baffled to learn that the company had designed an automated safety system that abandoned the principles of component redundancy, ultimately entrusting the automated decision-making to just one sensor — a type of sensor that was known to fail.

New Zealand's government on Thursday said it will end its quarantine requirements for incoming travelers and reopen its borders.

Delta Air Lines said Monday that new pandemic-related cleaning requirements at a Shanghai airport were behind the turning back of a recent flight from Seattle in midair.