= 140 + (H 47) A1 E1 – = 150 + (H 17) B1 – F1 – A1 = + 0.6870 0.7506 + 0.6 E1 xr –0.09707 – is such that: F1 = + 12.95 32.03 + 33.50 10.91 for 1.71 F1 xr xr –1.862 – – = 1.21 + 0.2 for > 1.71 F1 xr xr and varies with distance and skip distance as: a d ds = (d / (H + 140) a ds) – = 160 + (H + 43) ds G = + 19.50 63.15 + 90.47 44.73 for 3.7 G –2.102 – xr – xr = 19.25 for > 3.7 G xr b) For > 3.33 and < 1: x xr = or 800 km, whichever is the smaller (15) hr h = + for 0 h A2 B2 b B2 = + otherwise A2 B2 with: = 151 + (H 47) A2 E2 – = 141 + (H 24) B2 – F2 – A2 = 0.1906 + 0.00583 + 0.1936 E2 Z2 Z = 0.645 2 + 0.883 + 0.162 F2 Z Z = or 0.1, whichever is the larger and varies with normalized distance Z xr b df, and as follows: Z H = + 15.75 8.834 0.378 + 1 b –7.535 – – df where: or 0.65; whichever is the smaller c) For 3.33: x = 115 + + or 800 km, whichever is the smaller (16) hr H J U d with: = 0.7126 + 5.863 16.13 + 16.07 J y3 y2 y – – and = 8 10–5 (H 80) (1 + 11 + 1.2 10–3 U y–2.2) H y–3.6 – In the case of paths up to (km), is evaluated at the path mid-point: for longer paths, it is dmax hr determined for all the control points given in Table 1c) and the mean value is used.
A1 = 140 + (H – 47) E1 B1 = 150 + (H – 17) F1 – A1 E1 = –0.09707 + 0.6870 – 0.7506 xr + 0.6 F1 is such that: F1 = –1.862 + 12.95 – 32.03 + 33.50 xr – 10.91 for xr 1.71 F1 = 1.21 + 0.2 xr for xr > 1.71 and a varies with distance d and skip distance ds as: a = (d – ds) / (H + 140) ds = 160 + (H + 43) G G = –2.102 + 19.50 – 63.15 + 90.47 xr – 44.73 for xr 3.7 G = 19.25 for xr > 3.7 b) For x > 3.33 and xr < 1: hr = h or 800 km, whichever is the smaller (15) h = A2 + B2 b for B2 0 = A2 + B2 otherwise with: A2 = 151 + (H – 47) E2 B2 = 141 + (H – 24) F2 – A2 E2 = 0.1906 Z2 + 0.00583 Z + 0.1936 F2 = 0.645 Z 2 + 0.883 Z + 0.162 Z = xr or 0.1, whichever is the larger and b varies with normalized distance df, Z and H as follows: b = –7.535 + 15.75 – 8.834 – 0.378 df + 1 where: or 0.65; whichever is the smaller c) For x 3.33: hr = 115 + H J + U d or 800 km, whichever is the smaller (16) with: J = – 0.7126 y3 + 5.863 y2 – 16.13 y + 16.07 and U = 8 10–5 (H – 80) (1 + 11 y–2.2) + 1.2 10–3 H y–3.6 In the case of paths up to dmax (km), hr is evaluated at the path mid-point: for longer paths, it is determined for all the control points given in Table 1c) and the mean value is used.