Boeing 777X Structural Testing Halted Due To An Unexpected Event

According to several sources, an unexpected event occurred during testing of the Boeing 777X that forced the team to halt the tests. Boeing reports that the test team followed all safety protocols and that there were no reported injuries associated with the incident. As with many commercial aircraft tests, the plane is subjected to extreme situations and is components and systems pushed to their limits and beyond.

Boeing 777X airline orders
At least nine customers have ordered the Boeing 777X. Photo: Boeing

The aircraft door

According to Yahoo news, as well as local sources like KOMO and K5, the incident in question concerns a door being blown off the Boeing 777X. This incident is occurring at a time when federal regulators are supposed to be conducting their final structural inspection.

K5 reports that the test was inside of a building and force was to be added until the airplane eventually collapses. However, apparently a door inside the fuselage “had an issue” before crews got to their intended point of testing. Here is the series of events leading up to the incident, according to sources:

  • Engineers had the plane pressurized and on the ground.
  • The aircraft was loaded well beyond capacity
  • Its wings were “bent in an extreme manner, in a way almost certain to never happen in the real world”.

Then, as the ground test was underway, a door blew off the plane. This happened under the supervision of engineers and FAA inspectors. Sources reporting to KOMO say that there was a “stunned silence” after this happened. As a result, tests were suspended.

Boeing 777x
The 777X was originally scheduled to take off on its first test flight this summer. Photo: Boeing

Commentary and official response

KOMO spoke to a former Boeing engineer who said this type of incident doesn’t happen often, saying:

“I’ve never heard of a case where a door popped off like this during a stress test before. [That] doesn’t mean it hasn’t happened before, I’m just not aware of it.”

When asked for a comment, a Boeing spokesperson sent the following statement:

During final load testing on the 777X static test airplane, the team encountered an issue that required suspension of the test. The testing conditions were well beyond any load expected in commercial service. The event is under review and the team is working to understand the root cause. Final load testing is the last in a series of tests that Boeing has been conducting on this full-scale test airplane over the past several months.

Boeing also provided us more information about what final load testing is all about and provided assurance that safety was their priority:

“In final load testing, test articles are subjected to loads and stresses well beyond normal operational loads. This is one example of the comprehensive testing Boeing conducts to ensure that our products meet the highest standards of safety. The static test airplane is a test article that is used exclusively to conduct structural and certification testing. It will never fly or be used in passenger service. As part of our commitment to safety, Boeing conducts a series of thorough ground and flight tests of all our products, many of which are performed on the full-scale static test airplane.”

Not the time to race to conclusions

The former Boeing engineer emphasizes that this is not the time to race to conclusions, saying that it could be something “totally innocuous” causing the door to come off. However, it’s possible that this incident could cause delays.

“It’s unlikely this will speed up certification,” the source said. He goes on to say that it’s more likely it will make the certification team (from Boeing and the FAA) do extra work to figure out what happened.

Although the first Emirates 777X is nearing completion, the program as a whole has faced numerous delays. Issues, which include an engine recall, have meant that the first test flight won’t take place until 2020.

Boeing 777X 2020 Launch
The 777X builds on the 777’s design with features from the 787. Photo: Boeing


As one Simple Flying commentator mentioned, delays are part of the game for Boeing and Airbus. The fierce competition for orders has led both to over-promise on timelines and schedules. Many of the new aircraft types from both manufacturers have had delays in their entry into service (like the A380 and B787). As such, we should see these delays from Boeing as par for the course.

Would you agree? Or do you think that this time around it’s something more serious? Let us know by leaving a comment!