Abstract What is aeronautics? Put simply, it is thestudy and design of air- and space-craft. In theaeronautics strand of Governor’s Institute, wespent a week building and launching a delta wingaircraft. A delta wing is a plane with a pair of wingsthat fold out into a triangle shape.
Purpose The purpose of our project is to determine whatimpact a tail rudder will have on the movement anddistance of our craft. We will be testing a variety ofaluminum rudders. These rudders will be attached to alight-weight craft that will then be shot out of an aircannon.
Hypothesis The 60 degree rudder will cause the glider to flythe farthest. -Our reasoning for this was that the drag on the 60 degree rudder would compensate for the heavier front end of the plane, ultimately giving it more lift and making it fly higher and farther.
Procedure Day one: Rainbow Split 1.0 The fuselage of our glider is made of PVC, and our rudders attach via twopaperclips. Our wings are made from parts of an old umbrella (specifically themoving joints and the fabric). They are kept out by a set of rubber bands in a smallwooden housing. This craft turned out to be incredibly heavy, and didn’t fly well at all. Thetension on the rubber bands was too low to keep the wings fully open in flight, andthe wood components broke easily.
ProcedureDay two: Rainbow Split 1.1 We replaced the fuselage with wood, and redid the rubber band system. The tension is now mush tighter and any problems with the bands are easier to fix. However, our system for attaching rudders (not shown here) is still paperclips, which are not very effective.
ProcedureDay three: Rainbow Split 1.2 In this model, we added a better rudder attachment. It is a spring-loaded system that locks the rudder into place. It proved to be much more effective than the paper clips. We also spaced out the rubber bands so that the tension was greater.
ProcedureDay four: Rainbow Split 1.4 We created the design for the rudders we would use in testing and cut some of them out. We also added a metal support to the body and stitched it on. In addition to that, we added a bumper to the front of the glider to serve as protection against otherwise catastrophic nose dives. Rainbow Split 1.4 ended up being our final model, with only a few tweaks here and there. It was the lightest, most well-balanced of our models.
ProcedureDay five: Testing day! We pretty much just ran tests on day five. We did tweak a few things, such as the rudder attachment system and the bumper on the front. Our model held up well in testing until our second test with the 60 degree rudder, when the fuselage snapped at a weak point.
DataRudder Trial # Distance Flight Damage Wind Speed and Flown Time Report direction180 degree 1 80’8” 2.8 seconds Tail bent almost 180 degrees North, 12 mphrudder(control) 2 77’ 2.7 seconds Tail bent about 90 degrees North, 12 mph 3 136’2” 3.4 seconds Tail folded vertically in half Northwest, 9 mph 4 106’4” 3.0 seconds Tail bent slightly, wings ripped Northwest, 9 mph60 degree 1 97’2” 2.6 seconds No damage taken Northwest, 9 mphrudder 2 97’2” 2.6 seconds Fuselage snapped, forcibly concluding Northwest, 9 mph testing 3 N/A N/A Unable to continue testing N/A 4 N/A N/A Unable to continue testing N/A All launches were done at 55 PSI with a cannon height of 103 inches.
Results We found that the 180 degree (flat) rudder madethe glider travel farther, with an average flight distancethat was 34.5 inches greater than the 60 degree rudderand an average flight time that was 3/8 of a secondlonger. We think that this is because the 180 did notprovide as much air resistance as the 60 degree rudder.We originally thought that the air resistance from the 60degree rudder would balance the plane, but it ended upoverbalancing it instead.
Error Analysis In our experiment, although we tried to be as accurate aspossible, there was room for error. Some errors that could have affectedthe results are: Distance: When we measured flight distance, we counted paces. We put the pace length at 22 inches, although the length varied slightly with each stride. Wind speed/direction: we took the wind speed and direction from an online weather report as we lacked the equipment to measure them ourselves. Rudders: as shown in our data, our rudders were damaged in some tests. We lacked the material to built a rudder for each test, so we reused those that were damaged, doing our best to repair them without adding new materials. Flight time: we used a handheld timer and had to estimate when the plane left the barrel of the cannon, as well as when it landed.
Conclusion A flat (180 degree) rudder creates more balance for a glider, allowing it to fly farther and longer than a rudder that is at an angle. It also creates less air resistance. THE END