Hughes was not known as a sensible or particularly sane pilot
Don Rogers, who was CTP at Avro Canada in the early fifties, took the Avro Canada C-102 'Jetliner' (the world's second civil jet transport, first flew one month after the DH Comet!) to California for demos to TWA's owner.
Based at LA with the prototype for two or three months, was on standby 24/7 to be available at Mr. Hughes' whim. Don used to tell the story of getting the call in the dead of night, followed by an hour of VFR circuits, then await his next call. This went on for several months, all Don and family's expenses paid by Hughes.
Don always said Hughes was a good intuitive pilot, but not particularly methodical in his approach.
Looking at the inside of the Spruce Goose in the Long Beach museum many years ago, the structure hardly seemed strong enough to be airworthy, but who knows???