In Early September, Boeing began tests of their new flagship widebody airliner, the 777x; With the reputation of the 777 family on the line, the manufacturer, already plagued with issues on the 737-MAX family, were keen to keep the failings of the project quiet. However, in new images released today, the real result of the (reported failed) pressure testing on the 777x airframe, has been shown.
Initially, it was reported that the airframe failed testing due to a cargo door being unsealed properly, however it now appears it was not only the cargo door that exploded off the aircraft, but in-fact the fuselage itself that ruptured! According to test papers released by the Seattle Times, as the test was reaching it’s target level for success, an ‘explosive depressurisation’ ripped the fuselage apart. Photos from the incident, previously kept internally by Boeing, show large rips through the fuselage skin, as well as damage to cabling through the cabin. The prior report of a cargo door blowing off is entirely unfounded however. Also according to the report, damage was caused just behind the wing, causing the cargo door to ‘fall’ towards the hanger floor – Not explode violently outwards as initially reported.
What tests do aircraft go through?
Pressurisation systems ensure the correct cabin and hold conditions are met to sustain life at cruising and climb altitudes. At 36,000ft, passengers would face hypoxia (An acute lack of Oxygen to the brain), passing out in approximately 30 seconds, without a pressurisation system onboard. To successfully pass tests, aircraft have to withstand 1.5x the standard pressure experienced, and wings are ‘flex-test’ to withstand 28ft of flex from their natural position.
The FAA have however said that the airframe met 1.48x the operational requirements and thus will not need to be retested, adding:
What we’ve seen to date reinforces our prior assessment that this will not have a significant impact on the design or our preparations for first flight.”
Whilst this may seem alarming, 99% of the test threshold was met – A threshold unlikely to ever occur mid-flight – and Boeing have released a statement vowing to “look at the area of the keel to repair the weakness presented”. One thing to note however, is that the airframe used for testing has now been ‘written-off’ and will not be used for any future tests.
So what are your thoughts on this development in the 777x program? Are you still a Boeing fan? Let us know in the comments…
