A recent mention of this subject in Wikipedia’s random articles had me wondering what the intent of this design is. If I’m understanding correctly, it’s similar to what you’d get if you blended the wingtips of a biplane into a single circular wing. It seems to be associated mainly with VTOL design, but I don’t understand how this wing configuration contributes to vertical take off or landing.
|A coleopter is a type of Vertical Take-Off and Landing aircraft design where the fuselage is surrounded by an annular wing. The aircraft is intended to take off and land on its tail.|
The picture shows something like a fan jet with a cockpit in the middle.
You stand in the middle with a fan around you to take off and tilt forward to move forwards. It looks a bit annular 
I hadn’t spotted the fan jet deal between the fuselage and the wing. Ok now I get it, the wing doubles as a large ducted fan housing. Thanx.