Wright Stuff 2019 - Designs
Posted: December 11th, 2018, 8:39 am
Commercial Wright Stuff kits offer the convenience of “one stop shopping” for suitable balsa wood, parts, etc. Kits also help expedite construction. However, they are not necessary to win the Wright Stuff event. The best Wright Stuff teams that I have coached over the past 15 years did not build and fly kit airplanes. They won many gold medals in that event at regional and state competitions.
The commercial 2019 Wright Stuff kits vary in both cost and complexity and each one has it merits. However, some Wright Stuff teams cannot afford to purchase commercial kits or they may have waited too long and cannot obtain a kit soon enough. Other teams may prefer to build something different from the kit airplanes that most students will fly.
Except at the highest levels of adult AMA and FAI competition, the specific design of the air frame will usually not be a significant factor in determining the winner of an indoor duration rubber powered stick airplane flying event. A conventional indoor tractor configuration (prop in front) built with the maximum permissible wing & stab area and near the minimum permissible weight is all that is required to win any Wright Stuff competition in terms of the design of the air frame. Note that the weight of the prop is included in measuring the weight of the air frame. Trim, propeller size & configuration, rubber motor sizing, and winding are each far more important to success in Wright Stuff competition than the particular design of the air frame. Balsa wood selection, i.e. in terms of the appropriate density and stiffness, is important as the model should not be overweight yet at the same time it should not suffer from motor stick bending and/or unintended warping of the wing or warping of the stab. I have purchased excellent balsa wood at very low cost many times from different ACE hardware stores located in various parts of the country. Take a scale and a density chart with you and use them to help you select the best sheets and sticks.
Fortunately, plans for Wright Stuff designs by expert fliers for prior years can be found on the Internet and re-drawn by hand so that the wing and stab have the maximum span and chord allowed under the 2019 Wright Stuff rules. One example is the plan for the LIL LONGSTER for Wright Stuff 2015 that can be downloaded from the Plans Gallery at the Hip Pocket Aeronautics web site. Any Wright Stuff plan by legendary indoor flier Cezar Banks will also suffice. A well-illustrated article written by Chuck Markos about Wright Stuff describes the necessary building techniques and the basics of trimming and winding. Just search his name and “Wright Stuff” via the Google search engine and a link to the article will come up.
Students can build a winning Wright Stuff model from scratch for less than $5 in balsa wood, parts, and covering material. Special molded plastic parts like the Ikara prop hanger and rear hook are not essential. A simple thrust bearing can be made from a 3/8-inch long segment of 1/16-inch OD Aluminum tube. This tube can be secured to the underside of a balsa wood spacer fixed to the lower side of the front end of the motor stick with the entire assembly wrapped with thread and glued in place. Props can be made by cutting blades with conventional outlines from 1/32-inch sheet balsa, wetting and forming them on a cylinder, and then gluing them to flattened outer segments of round toothpick spars. The round inner segments of the toothpick spars can be inserted into a tubular hub with an ID of 3/32-inches made of stiff paper or Aluminum tubing and the blades rotated to produce a propeller with an appropriate pitch-to-diameter (P/D) ratio and glued in place using a simple 45 degree pitching jig constructed from scrap balsa wood. Purchase a 12-inch length of .031-inch music wire to bend the prop shaft and rear motor hook. You will have plenty extra if your first bends don’t turn out well. With such a high weight budget (8 grams) there is no need to use harder-to-find .020-inch music wire, and the .031-inch music wire fits much better (free spinning with no slop) inside the 1/16-inch OD Aluminum thrust bearing. Don’t forget to put a tiny washer between the prop hub and the thrust bearing. You can use grocery store produce bag available for free as the covering material for the wing, stab and fin.
There are no secrets to success in indoor rubber powered free flight. Everything that helps maximize flight times is well documented on the Internet. A well-built and properly adjusted homemade Wright Stuff airplane can beat any commercial kit Wright Stuff airplane.
Most students who participate in the Wright Stuff event would be pleased with flights over 60 seconds. Teams that put in a reasonable amount of practice time, e.g. 20 - 30 hours, can often break 120 seconds. The very top teams in Wright Stuff have typically practiced 40+ hours and have very experienced indoor fliers as mentors. These teams can sometimes break 180 seconds in a standard size high school gym. Regardless of how students fare in an actual Wright Stuff competition, it is very gratifying for them to see a model that they built themselves fly gracefully in circles inside a gym.
Students should always strive to do their best. However, the true value of the Wright Stuff event for students lies not in winning a medal, but in learning the fundamentals of aerodynamics, the importance of recording data, the constructive use of the experimental method, and how to perform under pressure.
The commercial 2019 Wright Stuff kits vary in both cost and complexity and each one has it merits. However, some Wright Stuff teams cannot afford to purchase commercial kits or they may have waited too long and cannot obtain a kit soon enough. Other teams may prefer to build something different from the kit airplanes that most students will fly.
Except at the highest levels of adult AMA and FAI competition, the specific design of the air frame will usually not be a significant factor in determining the winner of an indoor duration rubber powered stick airplane flying event. A conventional indoor tractor configuration (prop in front) built with the maximum permissible wing & stab area and near the minimum permissible weight is all that is required to win any Wright Stuff competition in terms of the design of the air frame. Note that the weight of the prop is included in measuring the weight of the air frame. Trim, propeller size & configuration, rubber motor sizing, and winding are each far more important to success in Wright Stuff competition than the particular design of the air frame. Balsa wood selection, i.e. in terms of the appropriate density and stiffness, is important as the model should not be overweight yet at the same time it should not suffer from motor stick bending and/or unintended warping of the wing or warping of the stab. I have purchased excellent balsa wood at very low cost many times from different ACE hardware stores located in various parts of the country. Take a scale and a density chart with you and use them to help you select the best sheets and sticks.
Fortunately, plans for Wright Stuff designs by expert fliers for prior years can be found on the Internet and re-drawn by hand so that the wing and stab have the maximum span and chord allowed under the 2019 Wright Stuff rules. One example is the plan for the LIL LONGSTER for Wright Stuff 2015 that can be downloaded from the Plans Gallery at the Hip Pocket Aeronautics web site. Any Wright Stuff plan by legendary indoor flier Cezar Banks will also suffice. A well-illustrated article written by Chuck Markos about Wright Stuff describes the necessary building techniques and the basics of trimming and winding. Just search his name and “Wright Stuff” via the Google search engine and a link to the article will come up.
Students can build a winning Wright Stuff model from scratch for less than $5 in balsa wood, parts, and covering material. Special molded plastic parts like the Ikara prop hanger and rear hook are not essential. A simple thrust bearing can be made from a 3/8-inch long segment of 1/16-inch OD Aluminum tube. This tube can be secured to the underside of a balsa wood spacer fixed to the lower side of the front end of the motor stick with the entire assembly wrapped with thread and glued in place. Props can be made by cutting blades with conventional outlines from 1/32-inch sheet balsa, wetting and forming them on a cylinder, and then gluing them to flattened outer segments of round toothpick spars. The round inner segments of the toothpick spars can be inserted into a tubular hub with an ID of 3/32-inches made of stiff paper or Aluminum tubing and the blades rotated to produce a propeller with an appropriate pitch-to-diameter (P/D) ratio and glued in place using a simple 45 degree pitching jig constructed from scrap balsa wood. Purchase a 12-inch length of .031-inch music wire to bend the prop shaft and rear motor hook. You will have plenty extra if your first bends don’t turn out well. With such a high weight budget (8 grams) there is no need to use harder-to-find .020-inch music wire, and the .031-inch music wire fits much better (free spinning with no slop) inside the 1/16-inch OD Aluminum thrust bearing. Don’t forget to put a tiny washer between the prop hub and the thrust bearing. You can use grocery store produce bag available for free as the covering material for the wing, stab and fin.
There are no secrets to success in indoor rubber powered free flight. Everything that helps maximize flight times is well documented on the Internet. A well-built and properly adjusted homemade Wright Stuff airplane can beat any commercial kit Wright Stuff airplane.
Most students who participate in the Wright Stuff event would be pleased with flights over 60 seconds. Teams that put in a reasonable amount of practice time, e.g. 20 - 30 hours, can often break 120 seconds. The very top teams in Wright Stuff have typically practiced 40+ hours and have very experienced indoor fliers as mentors. These teams can sometimes break 180 seconds in a standard size high school gym. Regardless of how students fare in an actual Wright Stuff competition, it is very gratifying for them to see a model that they built themselves fly gracefully in circles inside a gym.
Students should always strive to do their best. However, the true value of the Wright Stuff event for students lies not in winning a medal, but in learning the fundamentals of aerodynamics, the importance of recording data, the constructive use of the experimental method, and how to perform under pressure.