Note: not a duplicate of Can biplane or triplane designs be revived with modern materials?
This question compares a high performance triplane with high aspect ratios and high gap, to a monoplane. It does not explore materials engineering.
Wouldn't a triplane be much more efficient than a monoplane of same wing area?
Take a small GA plane, 1,000 lbs, 100sq ft of Wing area, 25' span, 4' chord, a pretty typical LSA/microlight. So, an aspect ratio of roughly 6, and a wing loading of 10psf.
NOTE: With a gap of 2 chord, I understand the efficiency of multi wing aircraft is almost the same as a monoplane. see graph.
Now make it a triplane, which reduces the chord to roughly 1.3, increasing the aspect ratio from 6 to 18, just like a glider. That's a 300% increase in efficiency, no?
Instead of a heavy spar for a thin wing, you could just put the stabilator at the wing tips joining the 3 wings: so no extra wing strut interference drag ( expect for a small amount of extra interference drag at 2 wings roots).
less weight( same wing area, but smaller lighter wings), smaller engine needed ( so could even go with smaller wing area) less induced drag (due to 3 times the aspect ratio) a less form drag ( same span, but thinner wings (66% THINNER(??) due to 66% smaller chord) a little more wing root interference drag, no extra wing strut interference drag less induced drag due to 1/3 the wing loading
NOTE: All this could only happen with a gap of 2 chord or more, where I'm told 2 wings act independantly without interfering with each other, just like a main wing and horizontal tail( which is a biplane of sorts)
Is this correct, at least conceptually?