Before revision: Thus: 15 /60 = 1/ 4 = 0.25 (true sine = 0.2588 , error = -3.4%) 20/60 = 1/3 = 0.33 (0.342, -3.5%) 30/60 = 1/2 = 0.5 (0.5, 0%) 40/60 = 2/3 = 0.66 (0.643, +2.6%) 45/60 = 3/4 = 0.75 (0.707, +5.7%) 50/60 = 5/6 = 0.8 (0.766, +4.2%) 60/60 = 1/1 = 1.0 (0.866, +13.4%) The angle is the angle of the wind or tide as it presents itself relative to the ship or aircraft, so if the wind is coming from the left at a relative angle of 30°, we use a sine of 0.5.
After revision: Thus: 10 /60 = 1/ 6 = 0.167 (true sine = 0.1736-4%DIF > ) 15/60 = 1/4 = 0.25 (0.2588, , error = -3.4%) 20/60 = 1/3 = 0.33 (0.342, -3.5%) 30/60 = 1/2 = 0.5 (0.5, 0%) 40/60 = 2/3 = 0.66 (0.643, +2.6%) 45/60 = 3/4 = 0.75 (0.707, +5.7%) 50/60 = 5/6 = 0.8 (0.766, +4.2%) 60/60 = 1/1 = 1.0 (0.866, +13.4%) The angle is the angle of the wind or tide as it presents itself relative to the ship or aircraft, so if the wind is coming from the left at a relative angle of 30°, we use a sine of 0.5.