If every time an experimental airplane showed a problem, the same noise was made as is made today over the story of the suspension of the Boeing 777X test flights, no one would get on a plane anymore. There was certainly not that much noise when the Airbuses were losing their paint, nor when they showed imperfections in the control laws, or when other manufacturers of aircraft engines, such as Rolls-Royce but not only, had to shorten the inspection times of their products. Simply, aviation is made like this and a famous saying in the sector, a mantra in schools for super-technicians, goes: “Learn to try, test to learn”. Instead, articles appear in rapid succession regarding every little issue that afflicts the American manufacturer, which may be going through one of the most complicated moments in its recent history, but has certainly not suddenly become a club of irresponsible people led by managers too tied to finance as some would like to make it appear. Indeed, the appointment of Robert Ortberg as the new boss on August 8 is a sign in the right direction.
“Kelly”, as he is nicknamed, comes from an engineering background, has a huge amount of experience in the sector and – I confess – as a former flight test engineer, I would have really liked a boss like him. Let’s get to the point: the Boeing -B777X program is seriously behind schedule. This new type of airplane flew in 2020 and has since continued the testing process in order to obtain certification from the US and European aviation authorities. This milestone should be reached in 2025 in order to then be able to deliver the first examples the following year to a dozen large airlines that have ordered them. The airplane is innovative in many ways and among the features that make it so there is also a new engine, the General Electric 9X, the largest and heaviest turbofan ever built. So in the project we find a new airplane that is tested equipped with an equally new engine; therefore, a double technological challenge that only a few manufacturers in the world have faced. After each test mission, checks and controls are necessary, because apart from computer simulations of how structures and components behave, without inspections no one can demonstrate that things work properly. So, a few days ago, during a scheduled inspection of the third B-777-9 test aircraft (designated WH003 and with identification marks N779XY), which took place at Kona Airport in Hawaii, Boeing identified a component that did not prove to be as robust as it should have been on paper, sorry, on the design monitor, revealing itself to be cracked, or with what are called “cracks”.
The company immediately announced the precautionary grounding of all three prototypes and said: “Our team is replacing the damaged part and will resume flight testing as soon as the aircraft are ready.” The damaged part is one of the titanium pylons (Thrust-link) that serve to attach the engine to the airplane, that is, a piece (made by Boeing with General Electric) that, when the airplane is on the ground, holds a nine-ton object attached to the wing, while in flight it withstands thrusts close to 50 tons, vibrations and enormous forces for almost all of the time, which on an airplane like this, during its operational life is about 20 hours a day out of 24. So, the news is that there is a defect – and later we will understand if it is due to the design, installation or use – but that it was promptly identified and will be resolved well before the B-777 goes into production. As Boeing itself stated on its social channels, “this event serves as a reminder of the complexities inherent in the development of cutting-edge aerospace technologies”. Boeing’s decision to interrupt flight tests, even at this advanced stage, means doing things properly rather than rushing to meet deadlines. Also because the goal of every experimental department within every aeronautical company is to test and whip up the projects so that customers can be provided with a safe, reliable and – in this case – highly innovative aircraft.
Of course, the B-777X program is behind schedule, the first flight took place on January 25, 2020, then the following year the two additional examples were added to the test program, but Covid caused a sharp slowdown. – not only to Boeing – and then the airplane suffered a negative event in flight (an uncontrolled trim variation), which implied the revision of flight control systems and software. In November 2022, the new GE9X engine caused problems and in this case too, the issue had to be studied and resolved by moving the program forward in time. Of course, those who sell are quick and have to put a date in the contracts while those who buy expect it to be a credible date. Then there is the ferocious reality of things never done before, therefore innovative, when the defects come to light because the “aviation system” bases its safety precisely on this concept: safety comes from reliability and reliability comes from time. And every time man has tried to ignore this law, he has done himself harm.
