The Professional Protractor Triangle with handle is larger than other navigation triangles on the market with legs that are 9.312 inches long and a hypotenuse (long side) 13.125 inches long. It has both 320mm & 1-80,000 scales and is constructed of heavy duty clear 5 mm thick acrylic for durability with a handle for ease of use. Both pencil and pencil sharpener are included with the Professional Protractor Triangle and this product is backed by our lifetime warranty.
- Slide two triangles to transfer course or bearing.
- Place protractor vertex over meridian of longitude to determine course or bearing
- Hole at the vertex of the protractor allows the point of the divider or pencil to be placed on a meridian for a quick accurate course measurement
- A string fixed through the hole can be used on a chart to determine a long distance course.
- On shipboard, a string through the hole with a weight can be used to determine a long distance course.
- Convert the protractor into quadrant to measure the altitude of Polaris to determine latitude at night. Use a string of fishing line tied to the vertex with a weight at the other end to determine the angle.
- Measure angle/altitude of on shore object (tower/lighthouse) to determine distance from your location. Add the bearing for a fix.