Well Rob, you have come through again with flying colors. I salute you and your search diligence!
The Count Gianni Caproni CA.60 NOVIPLANO Italian flying boat of 1921 could be considered a triple triplane, huge and bizarre in appearance and with not inconsiderable drag, (and evidently not enough stress engineering or precise cg determination). Noviplano meant 'nine wings' in Italian. It was sometimes called the 'Flying Houseboat' and other, shall I write-unmentionable names? It was designed to carry 100 passengers trans-Atlantic. Caproni had eyes on an even larger version!
There were nine rectangular wings in three groups of three stacked with near-countless vertical mid-wing struts and X-wire bracings, (a real bird-flock slicer). There was some wing dihedral; wingspan 98' 5". Wing area was TWICE that of a B-52 bomber. The equal-sized wings would be nearly equally loaded in flight, making it longitudinally unstable. Differential use of front and rear ailerons would have controlled pitch, supposedly. Length was 77'. Height was 30'. There were two sponson floats, one each inboard on the lower middle wings set.
The eight 400 Hp each liquid-cooled Liberty piston engines with individual coolant radiators posed even more drag. Their arrangement was unusual and bears description. The eight engines were arranged with three pulling and pushing on the front wing AND three pushing and one one pulling at the back, with two-blade props. The center engines had four-bladed props. Nota bene: that seems to add to just 7 engines, but text is accurate as copied/written.
The pilot was in an open cockpit, 8 crew size, but enclosed passengers had more window glazing than ANY airliner before or since my 2005 data. Oh, and did I write there were absolutely NO tail surfaces?
The only one built apparently made a pre-test short hop on Lake Maggiore, but the first official flight resulted in disaster. Rising just about 60 feet above the lake, it plunged nose down into the water, extensively breaking up. Apparently, some testing had shown need for a lot of lead ballast and this may have shifted in the flight. The test pilot Semprini emerged from the wreck "unscathed." A mysterious fire later destroyed the remains of the sole Caproni CA.60, ending any further production hopes or dreams.