Fast, long range and aerodynamic, the Wren is a small "drone cruiser" paper airplane. The Wren features a unique new tail design, combining conventional horizontal stabilizers with a butterfly tail.
Originally, the Wren was being developed to be a lightweight version of the SkyTraveler with a different wing fitted to negate the need for a staple as part of its counterweight. However, when the prototype aircraft was tested, it faced stability problems. To remedy this, I redesigned the tail (having determined the design was largely sound and just needed increased stability). To this end, I modified the design to feature a tail design like that of the SkyTomahawk family, which had proven quite capable. When fitted with the new tail, the aircraft flew straight as an arrow quite quickly. Based on the new aircraft's unique appearance and good performance, I approved the Wren for publication.
TAA USAF Designation: D400-1
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Step 1: Materials
1 Piece of 8 by 10.5 inch graph paper
Step 2: Begin Construction
First, begin by folding your your graph paper in half (excluding three boxes on the perforated side). Once the paper has been folded appropriately, make two marks--11 full boxes apart (allow for a further box back behind the airframe). Use a ruler to make a straight line with the length of 12 boxes directly up 1 row of boxes from the two marks you just made. Then make the stabilizers, spars and counterweight as shown. To avoid confusion, one line you will cut along has been omitted from the photograph.
After the fuselage is made, take another sheet of paper that is folded in half along the lines of boxes. Mark out the wing as shown (1 box of constant chord at the root; a leading edge sweep of 1 box of chord decaying every 3 boxes outward from the constant chord box; and a trailing edge sweep of 1 box of decay along the 4 boxes of wingspan). This will complete the wings.
Solid lines indicate places to cut. Dotted lines indicate fold lines.
Note: 1 box = 0.25 inches
Step 3: Making the Fuselage
Cut out your fuselage and fold its counterweights into place. Cut along the solid lines. Once this is done, fold along the vertical dotted line then fold the airplane in half along the center crease once again. Fold along the dotted horizontal lines then tape where indicated.
Step 4: Applying the Wings; Stapling
Cut out your Wren's wings and lay them beneath the fuselage. Apply tape where designated to secure them to the fuselage. Apply tape to the LERX joint and one staple where noted. The outer stabilizers should be perpendicular to the fuselage while the inner fins should be canted outward at roughly 45 to 60 degrees. This will complete the aircraft.
Step 5: Flight
The Wren is a stable paper airplane and handles quite well. Launches should be done at moderate to high speeds at neutral attitude. Test flights should be conducted to check the aircraft's trim is correct. Additional applicable surfaces include slats, flaps, flaperons, elevators, ailerons, spoilers, spoilerons and trimmable rudders. Enjoy!