File:Kid Flier 6.5 plans, improved, in color! A balsa wood stick and copier paper glider for first-time builders and fliers. (8606241195).png

This is the Kid Flier 6 1/2, a flying model (toy) glider that any child or adult can build in less than an hour. It will glide nicely indoors and work outdoors in light winds. Its not meant for muscular javelin throws like an all balsa wood glider, but it can be slid gently into the air, glide across a room, through a door. But not really for loops. Gentle is the key.

You could use wooden stick or plastic-tube coffee stirrers, straws or anything else light and reasonably stiff. If you were really gentle and careful, you might use a rolled paper tube for the fuselage. Experiment. How about a single 'tube' of corrugated cardboard? Or two? Thin styrofoam from a food container or product packaging?

A printed copy of this sheet should completely fill the 8 1/2 X 11 or A4 size sheet of paper its printed onto. The meander-like design at the top is 8 1/2 inches wide, 215.9mm. The subdivisions are 1 inch, 25.4mm. If your printer/copier puts a blank around the outside edge, check the fin and rudder outline or the top design. If they're 1 inch, 25.4mm or just 25.0mm, you're good. If the airfoil pieces are correct, the size of the balsa sticks are also correct and you can just mark them on top of the plan and then check when they're cut and sanded.

Whether you are building one of these for the first time or the 100th, marking the first and last inch of the main fuselage stick will give you all the location references needed to assemble the plane. The thickness of the fuselage needs to be tapered from fulll size to zero over the course of the last inch. The two extra balsa sticks for the wing mount are attached between the first inch mark and the second- right on top of the "second inch".

The single most important thing is the wing. Its a 2 1/3" (aka 2 3/8", aka 60mm) strip of paper, 8 1/2 inches wide in North America, 2xxmm, A4, in the rest of the world. Have a look: https://www.flickr.com/photos/wbaiv/5702862548/

A complete wing, horizontal stabilizer and fin/rudder are included in full size at the bottom of this drawing. A single sheet with 4 wings and 2 plane's worth of stabilizers and fins can be found at: https://www.flickr.com/photos/wbaiv/5692184819/

All my Kid Flyer 6.5 photos on Flickr are at https://www.flickr.com/photos/wbaiv/sets/72157608701302701/with/8606241195/

The first 1/4 of the paper- 2/3", aka 11/16", aka 15mm, is folded down and glued with common "glue stick" to the second 1/4. This makes the paper double thick at the front, and regular thickness in the back. Upside down, that's "c=----" The FOLDED EDGE is the structural stiffener for the wing. If you glue two strips together, not folded but cut separately, it will not be as strong. You could use a very thin bit of white glue instead of glue stick, but the glue stick is lighter and dries faster.

Once the leading edge is folded, you'll notice that the wing will balance at approximately 1/3 back from the leading edge. This 1/3 proportion is the only actual number you need to build flying model or flying toy airplanes.

If you push the wing forward very gently, in a horizontal position, as if attached to the rest of a toy airplane, it will fly. https://www.flickr.com/photos/wbaiv/5702863214/ Keep trying. Sometimes it will slide off to one side or the other, sometimes it will flop side over side, but sometimes, it will fly straight and level, descending. Keep trying. https://www.flickr.com/photos/wbaiv/5702294365/

For physics fans in the audience, the potential energy of the height above ground level is being converted to the kinetic energy of wing falling, but also to forward motion in the air. As the wing descends, it displaces the air below it. By folding back the front 1/4, you've changed the density of the wing, moving the center of balance forward. The wing tends to be a bit nose-down, a bit inclined. The air squeezed out by its falling is pushed back and the equal and opposite reaction pushes the wing forward.

Now take a moment to cut (scissors work fine) one 6 1/2" long and two 1" long pieces of 1/16" square balsa wood. The long one is the fuselage, the short ones are wing mounts. There are patterns with dimensions at the top of the plan. Make one piece that fits each set of lines. That's 1.5mm square by about 160 to 165mm for the fuselage, about 25mm for the pair of wing mounts. Also cut out a 1 3/4" (1.75") piece of 1/8" balsa wood for the nose block. That's 44 or 45mm, of 3mm square. https://www.flickr.com/photos/wbaiv/5702861754/

Mark the first 1" (25mm) at BOTH ends of the long stick. I'm showing the marks as "." below. I

. . . . . . . . . . . . . . . . . . . . bottom
front end . . .===.==============.=== . . .back end
. . . . . . . . . . . . . . . . . . . . top

Now take a nail file or sanding stick or sand paper and taper (sand down) ONE end, over the 1" length, from 1/16" to nothing. That's the back of the plane, where the horizontal stabilizer goes. The area removed is solid red in the drawing above. https://www.flickr.com/photos/wbaiv/5702292633/

. . . . . . . . . . . . . . . . . . . bottom . . . . ""--,, <-- TAPER
front end . . .===.==============.----- . . .back end
. . . . . . . . . . . . . . . . . . . . top

The thin end is the TOP of the fuselage, The wing will be glued flat onto the fuselage, the horizontal stabilizer will have its leading edge at the lower edge of the fuselage, and the trailing edge at the upper edge of the fuselage. The relative difference in angle is very important.

(I'm sorry its drawn upside down, but I don't have a character that will line up with the UPPER of the two lines making an equals sign "--==_". Whereas, the dash sign, "-" which you might expect to fit right down the middle of the equals, lines up more with the lower line. Oh well.)

Now mark the SECOND 1 inch (25mm) of the front of the stick:

. . . . . . . . . . . . . . . . . . . bottom . . . . ""--,, <-- TAPER
front end . . .===.===.===========.----- . . .back end
. . . . . . . . . . . . . . . . . . . . top

Use white or carpenters' to glue the two 1" (25mm) pieces on the SIDES of the long stick, the fuselage, starting at the 1" (25mm) mark at the OTHER end of the stick and going toward the middle.

(Use Courier New or another fixed spacing font for this part:) From the side, upside down, this will look like:

. . . . . . . . . . . . . . . . . . . bottom 
front end . . .===.===.===========.----- . <-- TAPER. . .back end
. . . . . . . . . . . . . . . . . . . . top

This view doesn't show the short pieces because they're along the long piece. But it does show the taper from the full thickness of the fuselage to nothing, over the last 1 inch / 25mm.

From the bottom, lying upside down on a sheet of wax paper or plastic wrap,, it will look like:

. . . . . . . . . . . . . . . . . . . bottom 
. . . . . . . . . . . . . . ===
front end . . .===.===.===========.----- . <-- TAPER. . .back end
. . . . . . . . . . . . . . ===
. . . . . . . . . . . . . . . . . . . . top

Except the sides of the short pieces will be actually touching the sides of the long piece. From top or bottom, you can't really see the tapper at the back end, but I want you to see that the wing mounts are 1 inch (25mm) from the FRONT of the stick, and the taper is in the LAST 1 inch (25mm) of the stick.

In the following side views, I'm using "[]]" to mark where the wing mounts are:

===.]].===========.----- . . . <-- TAPER. . .back end

Finally, glue the 1/8" (3mm) piece to the UNDERSIDE of the front of the fuselage. That is, to the other end of the same side of the sanded, tapered end,

NOW it looks like:

. . . . . . . . . . . #####. . . . .bottom 
front end . . . ===.]].===========.-----  . . . . back end
. . . . . . . . . . . . . . . . . . . . . . top.

Put the sticks aside to dry for a couple of minute and play with the wing a bit more. A really gentle launch will work remarkably well, and, if you think about it, the only purpose to the rest of the airplane is to make it easier to launch the wing successfully. And control the direction it goes in.

Now cut out the 1" X 1" (25mm X 25mm) copier paper square for the fin, and the 1" X 2" (25 X 50mm) rectangle for the horizontal stabilizer. Mark a center-line across the 1" dimension of the horizontal stabilizer, dividing it into 2, square, halves. Lightly apply glue to the diagonal , tapered, underside at the back of the stick. The one you sanded:

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . glue
. . . . . . . . . . . #####. . . . . bottom . . . vvvv
front end . . . ===[]]============----- . . . . back end
. . . . . . . . . . . . . . . . . . . . . . top.

Lay the centerline of the horizontal stabilizer onto the glue, double check that the stabilizer is straight across the stick and equal sizes on both sides of the stick:

. . . . . . . . . . . #####. . . . . bottom . . . ___ <-- horizontal stabilizer 
front end . . . ===[]]============.----- . . . . back end
. . . . . . . . . . . . . . . . . . . . . . top.

From the bottom, the whole thing, upside down, should look something like:

 . . .wing
 . . .mount
 . . . . v
. . . ====. . . . . . . . . . . . . .| . . |<-- horizontal stabilizer 
#####==.============.|:::::|   back end
. . . ====. . . . . . . . . . . . . .| . . |
===[]]============-----

If the stick is 'right side up", the trailing edge of the horizontal stabilizer will be higher than the leading edge. This will tend to push the tail down and thus the nose up- the opposite of what the wing does when you fly it by itself - it tends to rotate toward nose-down and go flop flop flop if not launched really steadily.

Putting a stabilizer out behind the wing is like putting feathers on an arrrow- they will tend to keep it pointing the direction it was launched, if they're straight. By adding the tail-down/nose-up angle, the horizontal stabilizer dynamically balances the wing's natural nose-down tendency. The stabilizer holds it very slightly nose-up. If the wing pitches nose-down, it raises the horizontal stabilizer, causing it to be pushed down by more airflow. So the two forces balance. Like the arrow feathers, or the rudder on a surf-board, the system is stabilized by negative feedback. Turn the nose up, and a restoring force pushes it back down. Push it down and the restoring force pushes it back up.

The original red-ink ball-point sketch I've been using is here: https://www.flickr.com/photos/wbaiv/5521647995/ I like this one better. Complete building instructions are at the original as well. \