Boeing Suspends 777-9 Certification Tests After Engine Mount Component Failure

Boeing has temporarily halted the certification flight tests for its 777-9 aircraft after discovering a malfunction in a thrust link mounting component of the GE Aerospace GE9X engine during routine inspections. This issue came to light following a lengthy certification test flight over the Pacific, marking a setback in the aircraft’s testing phase, which had only recently begun after nearly three years of delays.

The problem was identified after the third test aircraft, designated WH003, returned to Kailua-Kona, Hawaii, from a 5-hour and 31-minute flight. During post-flight maintenance, Boeing engineers detected that a component attached to one of the aircraft’s engines did not perform as expected. The company stated, “Our team is replacing the part and capturing any learnings from the component and will resume flight testing when ready.”

This interruption occurs just as Boeing was gearing up for the first phase of the 777-9 type inspection authorization (TIA), a series of FAA-mandated tests essential for the aircraft’s certification. These tests, which began on July 12, are crucial for gaining FAA approval and moving forward with the planned initial deliveries, still projected for late 2025.

The component in question is part of the aircraft’s dual fail-safe thrust links, which are crucial for transferring both vertical and lateral mechanical stresses between the engine and the aircraft frame. These Boeing-designed links are attached to the fan frame and are responsible for carrying mechanical loads, engine torque, and thrust to the aft engine mount.

Following the discovery, an immediate investigation into the component failure was initiated, and inspections on other active test aircraft—WH001 and WH002—have also been conducted. These inspections have unfortunately revealed cracks in the thrust links of these aircraft as well, prompting them to be placed in lay-up for scheduled maintenance at Boeing’s facilities in Everett and Boeing Field in Seattle.

Boeing has reassured all stakeholders, stating, “We are inspecting the flight test fleet for this condition. No near-term flight tests were planned on the other flight test airplanes, which have scheduled maintenance and layup activities. We are keeping the FAA fully informed on the issue and have shared information with our customers.”

Details regarding the specifics of the failure are still under wraps as the investigation remains ongoing. However, the flight data from WH003’s final flight indicates that the test involved multiple rapid accelerations and decelerations at an altitude of 38,000 feet, suggesting that the tests were designed to simulate extreme operational conditions.

This development is a crucial reminder of the rigorous nature of aircraft testing and certification, where safety and performance are tested to their limits to ensure the reliability of new aircraft before they enter service. As Boeing addresses these challenges, the aviation community watches closely, anticipating the successful resolution and eventual entry of the 777-9 into the market.

Related news: https://airguide.info/?s=777

Sources: AirGuide Business airguide.info, bing.com, aviationweek.com