These are often suggested as hypothetical options, with principles following along phraseological lines such as "two or more" (German "Zwei- oder …", though triplanes, per se, are sometimes named as such and-or depicted in diagrams.
This wiki has 10 patents in category "Triplane".
Patents in category Triplane
- Patent GB-1897-15221 (English title: Means and appliances for effecting Aerial Navigation, Inventors: Octave Chanute • Augustus Moore Herring)
- Patent HU-1916-79362 (English title: Three-cover aircraft)
- Patent FR-1909-407090.11562 (English title: Helicoplane-parachute, Inventors: Charles Wolf)
- Patent FR-1909-407090.11561 (English title: Helicoplane-parachute, Inventors: Charles Wolf)
- Patent GB-1910-11779 (English title: Aeroplanes, Inventors: Herbert Malcolm McNeill)
- Patent FR-1911-427668 (English title: Airplane with automatic stabilizers, Inventors: Émile-Antoine Corbillon)
- Patent GB-1911-12092 (English title: Improvements in or relating to Flying Machines, Inventors: Haydn Gough-Turner)
- Patent FR-1915-476681 (English title: Airplane of multiple levels(or wings) in which each level(or set of wings) works independently, Inventors: Alexandre Bezobrazoff)
- Patent DE-1916-324904 (English title: Biplane, or aircraft with two, or more, pairs of wings)
- Patent AU-1918-8217 (English title: Flying machine construction, Inventors: Federico Caproni)