Module 7: Upwind Sailing Angles

Transcription

1 Module 7: Upwind Sailing Angles US Sailing s REACH Program utilizes sailing as an educational platform, challenging youth to embrace education, establish a love of learning and explore productive Science, Technology, Engineering, and Math (STEM) based careers. Combining educators, sailing instructors, engineers, scientists with today s youth to provide them with a one of a kind authentic learning experience, giving students the opportunity to apply classroom learning in a cooperative work environment. Find out more information about US Sailing s Reach program. Purchase a full copy of the 10 module Reach Educator s guide. Register for US Sailing s one-day STEM Educator Course. Contact: Jessica Servis Reach Program Manager US Sailing JessicaServis@ussailing.org For more information visit: Reach.ussailing.org

2 Module 7 Subject Areas Geometry, Sailing Module 7: Upwind sailing How does geometry affect my sailing? Learn Sailing Right! Beginner Chapters 11, 12 & Intermediate Chapter 6 Summary Students learn the advantage of making a clean 90 degree tack when sailing upwind. They can then apply geometric principles to racing to create a winning race plan. Duration Lesson Time: Part I: 60 minutes Part II: 30 minutes Part III: 90 minutes Skills Prediction, Problem Solving, Calculating, Calculating Perimeter, Calculating Distance based on Angles, Estimation, and Conversion Sailing Skills Coordination between trim and steering, Anticipation of wind change Vocabulary Upwind, Tack, Right Angle, Over-Rotate, Isosceles Triangles, Right Triangles, Complementary Angles, Straight Line, Perimeter, No Go Zone, Polygon, Beating to Windward. Standards See Standards Correlation Charts related to the National Standards. Common Core Standards relate to mathematics and the K-12 Framework for Science Education relate to Science. Objectives Students will: u Gain an understanding of the geometry present in upwind sailing. u Review the properties of right and isosceles triangles. u Apply previous sailing knowledge to problem solve a new situation u Calculate and compare polygon perimeters as determined by upwind tacking angles. u Apply knowledge about complementary angles in relation to tacking and sailing a shorter distance.

3 Upwind Sailing Materials US Sailing - Learn Sailing Right! Beginner Chapter 11 & 12 Student Sheet 1 and 2 Rulers Protractors White/ chalk board Boats to sail one design Sailing Centers Students should relate tacking to geometry and over-rotating to losing ground, especially in races. Implement Parts I, II, and III on separate days or just implement Parts I and III in one 3 hour sailing class. At this stage students should have a strong grasp of up and downwind sailing. The more experienced your sailors, the more impact this lesson will have. Formal Classroom Settings Implement Parts I and II of the lesson on separate days. Discuss and review the characteristic of different types of triangles and the characteristics of polygons. Career Connection Engineers, Architects, Computer Graphic Designers, Robotics Engineers, Construction Workers, Interior Designers, Astronomists, and sailboat racers use geometry every day. Background Knowledge Students should know the definition of a triangle and the different types of triangles: isosceles, right, equilateral. A triangle is the simplest polygon. Review supplementary and complementary angles. Remind students that the interior angles of a triangle add up to 180 degrees. Students should understand that you cannot sail directly into the wind because of the no go zone. In order to sail upwind, one must sail approximately 45 to the wind, tacking back and forth. This is called beating to windward. When beating to windward one ideally wants to tack 90 degrees from starboard to port tack or vice versa. Students should know how to make the boat tack by pushing the tiller towards the sail until the main sail breaks the no go zone. A right triangle contains a 90 angle, the other two angles adding up to 90 and the total of all three angles = 180. When you over-rotate during a tack when sailing upwind the angle becomes greater than 90 degrees increasing the distance you need to sail. If you under-rotate through the tack the sails will not pass through the no go zone and the boat will lose speed and eventually come to a stop since the wind will not be applying pressure to the sails.

4 Module 7 Procedure Part I: Upwind Sailing Classroom - 60 minutes 1. Students should relate tacking to geometry and over rotating to losing ground, especially in races. At this stage students should have a strong grasp of up and downwind sailing. 2. So far, you have learned how to rig your sailboat, how to sail upwind, downwind, and on a reach, and you can safely depart and return from the dock. Today we are going to rely on all of your past knowledge by having a race. 3. Put the following problem on the board, If the wind is blowing from the North and you leave the dock heading south on a run (sailing downwind), what path will you take to sail home? Keep in mind you can not sail into the wind because of the no go zone. 4. Give students Student Sheet 1 and ask them to sketch out the problem. 5. After all students have sketched a course, prompt students to explain why they zigzag from the close-hauled port tack to a close hauled starboard tack. 6. Explain to students that this is called beating to windward. A tack should be 90 degrees from the port tack to the starboard tack. 7. Review Learn Sailing Right! Beginner, Chapters 11 & Draw the correct path on the board. 9. We have a problem: we are going to set up today s sailing course for a race, but we need to know how long the race course is in order to know how far we will travel. 10. We know the downwind leg is 1,000 feet, but we don t know the distance to sail upwind. Using the key ½ inch = 200 feet, calculate the perimeter of the course if each tack is 90 degrees. 11. Give students 5-7 minutes to calculate the perimeter of the course. 12. If some students finish early ask them to count how many right triangles are on the course.

5 Upwind Sailing Part II: Over-Rotating Through Tacks Classroom Activity - 30 minutes 1. Have students read Learn Sailing Right! Beginner, Chapter 12. Then ask, Can anyone tell me how many degrees are in a straight line, a circle, and a triangle? What is a supplementary angle? ( two angles that add up to 180 ). When you sail in a straight line, what is the angle of that line? (180 ) If you tack making a 90 turn, what is the complementary angle?. 2. When a sailor over-rotates on a tack, does it increase or decrease the angle to the wind? 3. Pass out Student Sheet 2. Tell students, Using a ruler and a protractor draw a race course with a windward leg of 1,000 feet. The sailor is over-rotating by 30, so each tack is 120. Rounding to the nearest inch, calculate the perimeter of this new course. 4. How much further does a sailor travel when sailing with 90 tacks than the sailor with 120 tacks? 5. If you over-rotate on three tacks making your angle 120 degrees, how much further did you sail? Part III: Pulling it All Together On the Water - 90 minutes 1. Set up the race course. 2. Use a modified starting sequence of 1 minute. 3. Put ½ the boats on the over-rotator team and ½ on the 90 degree tacker team. Those on the over-rotators must over-rotate by exaggerating their tack by a few seconds to point their boat past 90 degrees, stopping at approximately 120 degrees. The 90 degree tackers must attempt to make perfect tacks while sailing upwind. 4. Running a minimum of 3 races have teams alternate for the first two races and then have everyone sail for themselves for the last race. 5. This works best using trained staff to skipper on bigger boats. Resources Start Sailing Right! Chapter 12: Upwind Sailing pages US Sailing 2012 Portsmouth, Rhode Island The Symmetry of Sailing: The Physics of Sailing for Yachtsmen By Ross Garrett available through Amazon.com

6 Module 7 Coursework Name: Directions: Using a ruler, measure and calculate the perimeter of the course. Each tack is represented by an arrow and equal to a ½ inch. Module 7: Student Sheet 1 Date: Key ½ inch = 200 feet Course perimeter = feet

7 Upwind Sailing Charting A Course Name: Module 7: Student Sheet 2 Date: Directions: Chart the sailor s course 1. Using a ruler and a protractor, draw a race course with a windward leg of 1,000 feet. 2. Each tack of the upwind leg is 1 inch or 200 feet. 3. The sailor is over rotating by 30, so each tack is Rounding to the nearest inch, calculate the perimeter of this new course. 5. How much further does a sailor travel when sailing with 90 tacks than the sailor with 120 tacks 6. Using a ruler, calculate the perimeter of the course. Leg = x 2x = 3x = 4x = 5x = 6x = Course perimeter = feet Key I Leg = 1 inch 1 inch = 200 feet