China's ambition to rival Boeing and Airbus with its homegrown C919 passenger jet is hitting turbulent skies.

Boeing bid farewell to an icon Tuesday: It delivered its final 747 jumbo jet.

Boeing's stock dropped more than 12 percent at the open onCHICAGO - Problems with Boeing's 737 Max killed 346 people. Now the 737 Max crisis could delay or even end Boeing's plans for a new mid-size airplane, widely expected to be called the Boeing 797. Boeing says it continues to work on plans for the potential plane, even in the face of the 737 Max crisis. But that by the time Boeing was devoting most of its attention to the 737 Max crisis, not a new plane. And because it can't deliver any of the 737 Max jets it continues to build, deliveries fell to only 19 from 39 a year earlier.