I’m beginning to think that they they really don’t know how to build airplanes any more:

Boeing’s new widebody jet, the 777X, suffered a setback Thursday afternoon during a high-pressure stress test on the ground when one of the airplane’s cargo doors exploded outward.

One 777X employee working in a nearby bay at Boeing’s Everett plant said he heard “a loud boom and the ground shook.”

The accident happened to what’s called the “static test airplane,” one of the two airplanes in any new jet program that are built for ground testing only and will never fly. It was during the final test that must be passed as part of the airplane’s certification by the Federal Aviation Administration (FAA).

The failure of the door will require careful analysis to find out why it happened, and it may mean Boeing will have to replace the door and repeat the test.

The 777X program is already delayed due to a problem with development of the GE-9X engine that will power it. In July, Boeing CEO Dennis Muilenburg revealed on a quarterly earnings call that the first 777X intended to fly, which rolled out of the Everett factory in March, will not make it into the air until next year.

This ground test failure is another blow.

………

The massively larger wings of the 777X are also carbon composite, with a folding tip, and during Thursday’s test those must have flexed in a similarly impressive way to those of the 787. This time, however, though the wings did not give way; it was one of the doors that failed — an outcome that is definitely not supposed to happen.

Boeing is no longer an aircraft manufacturer, it’s a hedge fund pretending to be an aircraft manufacturer.