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!

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Louis Noto

What bothers me is how Boeing, as always, releases a statement which hides the details of the incident. They say nothing about a door coming off, but they make sure to emphasize how this was just a test model subject to extreme forces. Boeing continues to show that they utterly refuse to be held accountable for their problems. Be honest, tell us what happened, provide some sort of explanation that doesn’t treat the public like stooges. Instead they immediately default to obfuscation, as per the Boeing Playbook. Boeing repeatedly says that safety is their top priority. Yet they continue to… Read more »


The next thing we’ll find is probably the blown off door is certified acceptable since they repeatedly mentioned that commercial operations will never operate anywhere near these conditions.


“stunned silence” Is anyone else getting the feeling that perhaps aircraft are being pushed to close to their limits? In search of ever lower fuel cost savings, manufacturing efficiency and jamming in as many people as possible – margins are being cut ever so close? I know part of the issue is the consumer who demands the lowest price possible, but methinks Exec’s (and this is just not an airline industry problem) who’s focus is mostly on share price, dividends and stock options – and work in the aircraft business really run the risk of a disaster (Hello there 737… Read more »


Maybe the acft builders should adapt a little of the old Mercedes Benz attitude: we know what the customer needs. The customer is not always right.


Looking at the scope of changes made during the development of the B777X, this issue appears to me more like a manufacturing defect which might even have effected the current B777. Poor quality of door frame has been previously reported on the B737NG the recent slats and flaps issues effecting both the current B737NG and MAS were only discovered due to the grounding.
Undoubtedly these defects might be a result of cost cutting measures over the years coupled with superficial testing which brings us to current state.


Sounds about right, Vince. And these are the same guys who wanna sell an aircraft with folding wings…


Hi Fly ‘s gonna get veeeeery busy filling all the gaps left by all those half-baked new aircraft and engines out there. Aren’t there already preproduced 777Xs for Emirates and Lufthansa? Produced even before certification and flight testing? It’s gonna get really tight on Boeing’s parking lots when they have to store those 777Xs because of maybe? possibly? a structural design flaw next to all those MAXes… Oh Boeing, where are You going? But hey, there is a good thing: the new GE engines are delayed anyways so Boeing has the time to do their homeworks with that door consruction!… Read more »


Yup, pre-produced aircrafts before any crucial testing was done to see if any changes in designe need to be made to ensure safety and stability of an aircraft, but hey let’s built half of them now so they can roll them out like hotcakes when they get the green light. I’m shocked that Boeing would even start 777x production before any of the critical structural and pressurized tests were carried out.


The parking lot is getting really full indeed! Regardless of manufacturing defects or design flaw that caused the door to blow off, it is going to be another costly patch on the aircraft for boeing. Emirates has outright rejected the first aircraft and gave it to lufthansa because they do not want an inferior aircraft with weight issues and patches in their fleet. Boeing is going to have a lot of explaining to do to Emirates and possibly Qatar.

Low flying

Wow. A lot of conjecture here. Maybe the Boeing and FAA engineers will analyse this and come up with a way forward. Some of them may have more relevant experience and knowledge than some of us, maybe.
Remember, sometimes you have to fail to succeed! Tests are done for a reason.


Perhaps – but given the nature of the failure and the response of those in attendance, the emphasis of what happened is serious. Imagine while flying, for a split second, the airframe is subject to the same stresses and a door blows out. It’ll result in an entire aircraft loss. Boeing has to go back now and redesign the doors and figure out why it happened – with already produced aircraft sitting on the ground. It’s akin to building a house, only to find the foundation will not support the weight, when the wind blow over 100 kph. No –… Read more »


Can’t Boeing just develop a software patch to stop the door from flying off? that seems to be their answer to everything.




It is crazy to start production before testing or certification, or to build an airframe around an engine that again was untested. I agree where will all these built but useless planes go, and how will the “fix” be rettro fitted if indeed it can be, to the production aircraft?
This is nothing but a complete mess.