The Rinspeed doesn't actually fly at all, that was assumed because of the way
the press release was translated from German in to English, think of the word
In boat mode the "spoiler" at the back flips underneath and it has enough power
to gets up on the plane so it "flies" about 18 inches above the water.
There have been a few attempts at building triphibians but they start as an
aircraft, if it's a seaplane it's considered a biphibian and if you can fold up
the wings and drive it along the road it's a triphibian.
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