FrenchPotatoEye wrote:https://boeing.mediaroom.com/news-relea ... tem=130500
All true. But they can test fly around it. The FAA has to be satisfied before they do their final checks (FAA personnel flying the plane). In the meantime, they certainly can fly without pressurizing the cargo hold if they want to get started.
Since the failure happened at ~149% of limit load, there is no reason why they cannot pressurize the hold to normal values as they are well below the failure point.
Where is this 149% from? Is it official that this was the percent?
CHICAGO, September 10, 2019 – During final load testing of the 777X static test airplane, a test which involves bending the wings of the airplane up to a level far beyond anything expected in commercial service, an issue arose that required the team to suspend testing. The testing issue occurred during the final minutes of the test, at approximately 99 percent of the final test loads, and involved a depressurization of the aft fuselage.
The test team followed all safety protocols, and we are conducting a comprehensive root-cause assessment over the coming weeks. The static airplane has been successfully undergoing testing since June, and this was the final test for the static test article. While our root cause assessment continues, at this time we do not expect that this will have a significant impact on aircraft design or on our overall test program schedule. We remain fully focused on safety as our highest priority, as we subject the 777X to a rigorous test program prior to first flight.
So it was doing the final test after months of testing, taking it far beyond any level of commercial flight i.e. doing the 150% load test, where it failed at approx 99% of final test load thus 150%*.099 = 148.5% which some round up to 149%.
I remember first flight(s) of previous new passenger aircraft took hours, covered a lot of primairy testing and expanded the flight enveloppe quickly. A "look it can fly" first flight seems hardly desirable from a PR standpoint..
That is just the way you are choosing to characterize what the first flight would be.
As above, the only authoritative statement we have is the static load test issue is not expected to have a significant impact on overall test program schedule.
To me that suggests they do not need to hit the 150% load before first flight, or they have a path to a solution that will be in place by the first flight without impacting the overall test program schedule.
The whole "can they fly the plane unpressurized" is a red herring, IMO, but as far as I know one certainly can fly a plane on an experimental certificate without the cabin being pressurized.