The jumbo jet, for many years the workhorse of modern air travel, could be close to running out of runway.
Last year, there were zero orders placed by commercial airlines for new Boeing 747s or Airbus A380s, reflecting a fundamental shift in the industry toward smaller, twin-engine planes. Smaller planes cost less to fly than the stately four-engine jumbos, which can carry as many as 525 passengers.
The slump in sales of the jets has raised questions over how long manufacturers can sustain production. It has also fueled internal debate in both companies over the future of the planes, sources said.