The Simple Cirrus' development was spurred to produce a more aerodynamic successor to the Simple SkyTomahawk. While the Simple SkyTomahawk performed admirably, I felt that its large stabilizers produced excessive drag and that a new design could be made that would lessen it, thereby increasing performance. To this end, I decided to modify the aerodynamic Cirrus and fit it with a wing like that of the Simple SkyTomahawk. In flight testing, the prototype proved that the change was fitting and its performance was excellent. Publication was approved quickly afterward.
TAA USAF Designation: D416-3
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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--13 full boxes apart (allow for a further box back behind the airframe). Use a ruler to make a straight line with the length of 13 boxes directly up 1 row of boxes from the two marks you just made. Then make the stabilizers, spars and counterweight as shown.
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; Stapling
Cut out your fuselage and fold its counterweights into place. Cut along the solid lines and cut off the left fin at the bisected solid line as shown. Once this is done, fold along the vertical dotted line then fold the airplane in half along the center crease once again. Fold the spars down along the dotted horizontal lines then tape where indicated.
After the taping is done, cut the rear fuselage away below the diagonal line. Fold the horizontal stabilizers down then apply one staple in the area of the counterweight as noted in the photograph.
Step 4: Applying the Wings
Cut out your Simple Cirrus' wings and lay them beneath the fuselage as shown. Apply tape where designated to secure them to the spars. Apply tape to the LERX joint where noted. This will complete the aircraft.
Step 5: Flight
The Simple Cirrus is a conventional and aerodynamically clean design; it is similar in its handling characteristics to types like the original Cirrus and Simple SkyTomahawk. Origami aviators with experience with either of those two types should have little difficulty transitioning to the Simple Cirrus.
Launches should be done at neutral or negative attitude at slow to moderate speed. Test flights should be conducted to see what trim (if any) the aircraft needs. Additional applicable surfaces include flaps, ailerons, elevators and a trimmable rudder. Enjoy!