What is your bill of material (BoM) AUW?
Believe a set of Edgley Optica plans~multiple views are available for a basis of design...which I believe to be a ducted prop, not
a ducted fan blade. Using a ducted prop will simplify construction as it affords less cost and more internal room than helix blades.
There is a diameter to duct length ratio providing greater thrust...copying the multple view spec should accomplish what's desired.
ENGINE1 x Avco Lycoming IO-360 flat-four piston engine driving a ducted fan, 149kW WEIGHTS Take-off weight1236 kg2725 lb Empty weight850 kg1874 lb DIMENSIONS
Wingspan11.99 m39 ft 4 in Length8.15 m27 ft 9 in Height2.31 m8 ft 7 in Wing area15.84 m2170.50 sq ft
Plans available from MODEL AVIATION
June 2000 issue plan#890 Construction pictures