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July « 2010 « Howard Fink — My Paper Airplanes

Howard Fink — My Paper Airplanes Paper Airplanes

July 26, 2010

Paper Airmanship

Filed under: Uncategorized — admin @ 3:25 am

Like the previous post, this is excerpted from “How To Make And Fly Paper Airplanes,” by Captain Ralph Barnaby, U. S. Navy, Retired.

Launching a Model in Aerial Maneuvers

The kinds of maneuvers that can be made with paper airplanes depends on (1) adjustments of control surfaces before launch, since there is no way of changing them in flight, and  (2) technique of launching.  Technique of launching in turn breaks down into speed of launching, attitude of model at time of release and direction of release.

The maneuvers most easily performed with  paper airplanes are circles, turns and loops.  But before a model can execute any maneuver it must be made to fly a straight-line glide.  This is critical.  If a model does not fly a straight glide, it will not perform maneuvers properly.  So let’s review the straight glide launching.

Hold the Barnaby model by the body ahead of the trailing edge.  Make sure the wings are level and aim the nose along what you believe to be the normal glide path.  Move the model ahead along the projected flight path at what you estimate to be the gliding speed.  Release the model.

Take care that you do not alter the attitude of the model as you launch it.  Keep your eye on the model and concentrate on the center-line.  Think of moving your hand in a path parallel to the center-line.

Also, don’t release the model with a snap of the wrist.  You will change the model’s flight path.  Instead, follow through with your launching arm.

Remember, practice makes perfect!

Once you have the straight glide launching down pat, you are ready for maneuvers.

Circles

Circular flights are made in a path more or less parallel to the ground.  Most paper airplanes, except the darts, can fly circles, but the best performers are models with greater wing span like the Barnaby and the swept-wings.

Whether a model flies a full or partial circle depends on (1) the amount of up-elevator applied, (2) the angle of bank at which the model is released and (3) the speed of launching.

flyingHere are directions for launching models in left and right turns.  I assume you are right-handed.  If you are left-handed, simply alter the instructions as necessary.

Grasp the model by the nose.  Hold the model in a vertical bank, underside toward you.

Now, for a circle to the left, hold the model at your left, nose pointing toward the right.  Quickly and smoothly draw your hand straight across to the right.  Release the airplane without changing this line.  Any twist of the wrist will cause erratic flight.  Launched properly, the model should fly a circle and then, if enough altitude remains, finish up in a straight glide.

For a circle to the right, hold the model out at your right, nose pointed to the left.  Pull your hand straight across toward the left and release the model.

For a complete circle that returns to your hand, hold the model clear up on the edge and launch it at high speed.  I have had some models that would perform two complete circles and return to my hand.  Such trick flights depend on precise balance and careful launching–both of which require considerable practice.

Turns

A turn is simply an incomplete circle.  So to make your model fly a turn hold it in position for a circle, but bank it less and don’t push it so hard.  The model should fly part of a turn, then straighten out into a normal straight-line glide.

holdingIf you find you do well with turns, you might try your hand at S-turns.  For a left-right S-turn, give your model a little right rudder and then launch it in a left turn.  The model should fly part of a left turn, slow down, level out and go into a right turn.  For a right-left S-turn, simply reverse the procedure.

Whatever you do, don’t try to fly turns with a poorly aligned model that turns when launched into a straight glide.  If it has a tendency to turn, say, to the left when launched straight, it will lose altitude or dive on being launched to fly a left turn.  When launched for a right turn, it will climb.  On the other hand, if a model makes perfect turns in both directions, it is pretty sure to fly straight when so launched.

Loops

Loops are made in a path perpendicular to the ground.  To prepare your model for a loop, you must first, of course, get it to fly a straight glide.  Your next step is to give the model extra up-elevator.  Curl up the trailing edge of the tail somewhat more than for a normal glide.

innerloop1

Grasp the Barnaby by the leading edge and launch it fairly fast on a slightly downward path, as seen at the left.  If the model does not fly all the way around a loop, try a faster launch or more up-elevator, or perhaps a little of both.  Be sure the wings are level at launch.  If the model is tilted sideways, it will do a climbing turn and dive instead of a loop.

After completing a loop, a model will probably do a series of roller-coaster dives and climbs.  If properly balanced, they should gradually dampen out into normal glide–possibly with slight up-and-down undulations because of the stabilizing effect of the increased elevator.

There is another way to loop the loop.  Hold the model nose-up with the top surface away from you.  Now pull the airplane straight up, releasing the model in front of your face.  The airplane should loop away from you, then return so you can catch it in your hand.

outerloop1

The Barnaby

Filed under: Uncategorized — admin @ 1:14 am

barnaby

Captain Ralph S. Barnaby, U.S. Navy (Ret.) won the Aerobatics, Professional category at the 1967 International Paper Airplane Contest.  He was persuaded to write a book, which came out in 1968, titled, “How To Make & Fly Paper Airplanes,” published by Scholastic Book Services.  I used this book to learn how to make and fly the prize-winning plane, and continue to make and fly planes based on the Barnaby design.  What follows is an excerpt from that book, long out of print, although it went through at least 7 editions.

The Barnaby and Other Models

I had the good fortune to grow up during the years that the Wright brothers were building and flying their aircraft.  During the summer of 1908, the Wrights were making their first public flights — Wilbur in Europe and Orville in the United States.  I was spending the vacation working in my father’s engineering office in New York City.  I followed eagerly the reports of the Wrights’ exploits and resolved then that aviation would be my field.  I started folding up and flying paper airplanes, using office stationery.  That explains my preference for 8 1/2-by-11-inch bond.

The model I developed then has remained substantially unchanged over the years.  It resembles more than most models I know the popular light airplanes like the Piper Cub, the Aeronca and the Cessena.  Like them, the Barnaby is a versatile flier.  With slight adjustments, it is capable of performing straight glides, right and left circles that return to the hand of the launcher, and perfect loops.

For a really neat job, you’ll need a pair of scissors to cut the paper to its final planform.  But it is quite possible to tear the paper to shape by hand and get acceptable results.  In fact, I acquired my tearing skill while making free balloon flights from Wright Field, near Dayton, in the late 1920’s.  I would while away the time by tearing out, folding up and dropping paper gliders from the balloon–then watch them circle below until lost from sight.

How To Build A Barnaby Model

folding

Here’s how to make a Barnaby model.  Take a sheet of 8 1/2-by-11-inch bond paper and fold it in half widthwise.  Open it and lay it crease down on a hard flat surface.  This crease will be the model’s centerline.

Fold over a 1/4-inch strip along one of the 11-inch edges.  Do this in one operation, using the fingers of both hands.  The fold must lie flat.  Continue folding until at least one-half of the sheet has been folded up.  Remember, each fold must be carefully flattened in a separate operation.  Otherwise, you may build a twist into the leading edge.  Later, when you try to adjust the model, the wings will not align.

making

Now bring the two rolled-up tips together and press again along the centerline.  Hold the paper in this position and carefully cut or tear along the dotted line, as indicated in the figure.  Spread the model out flat and turn up a quarter inch of each wingtip to make wing fins.  These fins should be parallel to the centerline and perpendicular to the wings.

Next, fold down the outer portions of the tail surfaces to make rudders, following the angle made by the dashed lines in the figure.  Note that these folds are not parallel to the centerline but toe in slightly toward the nose.

With the thumb and index finger, bend up a small portion of the rolled-up leading edge at the centerline.  This raised portion will act as a truss to stiffen the wings laterally and hold them at the proper angle.

Now camber the  wings by scratching along their trailing edge.  Hold the model by the tail, between the thumb and first two fingers with the index finger on top and check for symmetry.  If necessary, add more camber to one wing or smooth one out until the two are identical.

Also check for wingtip symmetry by viewing the model from the side.  If the leading edge has been folded right, the creases of the wingtip fins will appear parallel to the centerline. (i)   If  the leading edge has not been folded right, these fins may be twisted down (j), or one may be twisted down and the other up (k).  It’s practically impossible to get rid of such a fault once it has been folded into the paper.  It’s easier to start over again with a fresh sheet of paper.

Finally give the model a little up-elevator by pinching a bit of the center fold at the tail (l)

You are now ready for launch.  Hold the model as shown in the  figure and push it gently away from you on a slightly downward path.  If you have correctly executed each step in construction, your model should glide along nicely.  If not, adjustments must be made.

trim

How to Make Adjustments

If the model dives into the ground, give it a little more up-elevator by cambering the trailing edge of the tail upward by pinching the fold in the tail a little tighter.  If the model follows an undulating path, it has too much up-elevator.  Try flattening down the trailing edge of the tail.  If this doesn’t work, chances are your Barnaby is tail-heavy because you did not roll up enough paper in the leading edge.  This can be corrected by adding a paper clip to the nose.

If the model glides all right but tends to yaw, check again for symmetry.  Make sure both wings have the same amount of camber.  And make sure, too, that both rudders have the same amount of tow-in.  If the airplane still tends to yaw, increase the camber on the side to which it turns.  Then bend the trailing edge of the rudders toward the other side.  Remember to keep your corrections small.

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