The black series continues for the American contractor, Boeing has suspended testing of its Boeing 777X aircraft after an explosion of cargo door during a stress test.
“During final load testing on the Boeing 777X static test airplane, the team encountered an issue that required suspension of the test,” Boeing spokesman Paul Bergman said in a statement on Saturday.
A 777X employee working near the Boeing Everett plant told the Seattle Times that he heard « loud noise and the ground was shaking ». The incident happened on a « static test plane », one of two new jet program aircraft designed for ground testing only, that is, it was intended that would never fly. The problem occurred during the final test to be completed as part of the aircraft certification by the Federal Aviation Administration (FAA), the US newspaper reported. The explosion of the cargo door, which has not injured anyone, will require careful analysis to determine the cause of the problem, which may mean that Boeing will have to replace the door and repeat the test.
The 777X program is already delayed due to a development problem with the GE-9X General Electric engine that will power it. In July, Boeing CEO Dennis Muilenburg revealed in a quarterly earnings report that the first 777X to fly from the Everett plant in March will not be launched until next year. This failure of the ground test is another blow. Boeing is no longer able to deliver any of its 737 MAX aircraft since the single-aisle aircraft was stopped around the world in March after two fatal accidents in Indonesia and Ethiopia killed 346 people.
The static test plan is one that is deliberately solicited well beyond the limits of the conditions of normal operating service, said the spokesman, adding that the incident was being reconsidered. The aircraft is surrounded by a metal frame while the weights passing through the pulleys are attached to the wings and other parts of the cell. In addition, the covering panels that cover both the wings and the fuselage are pressurized to obtain the maximum stress expected during an extreme maneuver planned in service. The pressure is increased by pumping air into the cabin. The Seattle-based newspaper goes on to say that the carbon composite wings of the 787 are so flexible that when Boeing tested them in 2010, they curved upwards of about 25 feet. After having largely exceeded the target load, Boeing stopped the test without breaking anything. The massively larger wings of the 777X are also made of carbon composite, with a collapsible tip, and during Thursday’s test, they had to flex in the same way as those of the 787. So it’s the cargo door that has yielded under the constraints imposed by the test.