ORAC told us:
Brig. Gen. Duke Richardson, the program executive on the Air Force’s next-gen tanker program, told an audience at the Air Force Association annual convention that a continuing resolution (CR) would create a “very large problem” for the program.
Well, Gen Duke has now given an "exclusive" interview to Aviation Week, in which he said there were three separate problems, not including the corrosive chemical contamination.
First, and likely the most major problem, was a deficiency in the fuel-system manifold that routs fuel throughout the tanker. .... “It failed a stress test. .... Richardson tells Aviation Week during a Sept. 16 interview .... The problem came to light during qualification testing required for
FAA certification, and Boeing notified the service of it in February.
Then there was
an issue with welding that connects the fuel tubes in the system and an issue with how the fuel tubes are attached to the inside of the aircraft.
You can find all the gory detail at
KC-46: What Was Wrong With The Fuel System | Defense content from Aviation Week
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