Mark Grid Antenna by mWAVE Industries LLC
Call Us Free: 1-800-123-4567
Breaking News: mWAVE, Gabriel and Mark Grid are now part of the Alaris Holdings Group of Companies

Windload Information

Request A Quote | Recent News

Wind Forces and Loads

The wind’s direction and magnitude must be defined because it is a source of force on an antenna. This vectorial quantity is broken down into two forces and a moment as shown in Figure 1. FA , axial force, acts upon the axis of the antenna and passes through the vertex of the reflector. Fs , side force, acts perpendicular to the axis of the reflector and also passes through the vertex of the reflector. M, twisting moment, acts in the same plane as the horizontal axis of the reflector. Should the antenna mounting be such that there is an offset of the antenna axis from the mounting axis, additional moments are generated.

Windloading Diagram Grid Antenna

These are four factors that determine the magnitude of the three forces generated by the wind:

  • Wind speed
  • Antenna size
  • Wind angle striking the antenna
  • Antenna shape

The wind speed is usually considered as a maximum. The antenna size is defined. The wind angle is a constantly changing variable and is normally considered at that angle that generates the maximum loading.

Windload Diagram Mark Grid Antenna

To fully evaluate that variation of those forces, that are usually expressed in terms of coefficients:

C = Coefficient
A = Frontal area in square feet
V = Wind velocity in mph
D = Antenna diamter in feet
CA = FA/AV2
CS = FS/AV2
CM = M/DAV2

The actual force on the antenna mounting pipe must take into account the offset introduced by the antenna mount. These are shown in Figure 2.

X = Offset of the mounting pipe in feet (meters)
Y = Distance on the reflector axis from the reflector vertex to the center of the mounting pipe in feet (meters)

The total moment and forces exerted on the antenna mounting pipe can be determined by:

FA = FA
FST = FS
MT = M + FA(X) + FS(Y)

Using these coefficients, the following forces are generated for antennas at 125 mph (200 km/h). These are not the worst cases, but typical values.

Table 1

Typical coefficient value form solid antenna graphs based on RS-222

Wind Angle CA CS CM
0° 0.00397 0.00000 0.00000
45° 0.00417 0.00012 0.000157
90° 0.00003 0.00088 0.000336
135° 0.00134 0.00117 0.000356
180° 0.0027 0.00000 0.00000

Note: All antennas conform to specifications TIA/EIA-222-F and EIA-195-C.

Mark Parabolic Grids

350 -1000 MHz / 0 – 180° Angle / Without Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 1.32 0.12 83 369 — — 33 45
4 1.2 4.55 0.41 284 1264 — — 130 176
6 1.8 7.85 0.71 491 2185 — — 286 388
8 2.4 11.92 1.07 745 3315 — — 435 590
10 3 16.4 1.48 1025 4561 — — 598 811
12 3.8 32.18 2.91 2011 8949 — — 1173 1590
15 4.6 42 3.78 2625 11681 — — 1531 2076
350 -1000 MHz / 90° Angle / Without Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 0.56 0.05 — — 35 156 20 27
4 1.2 1.65 0.15 — — 103 458 74 100
6 1.8 3.11 0.28 — — 194 863 140 190
8 2.4 5.41 0.49 — — 338 1504 243 329
10 3 7 0.63 — — 438 1949 314 426
12 3.8 10.4 0.94 — — 650 2893 596 808
15 4.6 21.75 1.96 — — 1359 6048 1246 1689
350 -1000 MHz / 0 – 180° Angle / With 1/2″ Radial Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 3.66 0.33 229 1019 — — 91 123
4 1.2 7.7 0.69 481 2140 — — 221 230
6 1.8 14.33 1.3 896 3987 — — 522 708
8 2.4 22.93 2.06 1433 6377 — — 836 1133
10 3 33.07 2.98 2067 9198 — — 1206 1635
12 3.8 52.57 4.73 3286 14616 — — 1917 2599
15 4.6 83.66 7.53 5229 23269 — — 3050 4135
350 -1000 MHz / 90° Angle / With 1/2″ Radial Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 1.33 0.12 — — 83 369 48 65
4 1.2 1.92 0.17 — — 120 534 86 117
6 1.8 3.11 0.28 — — 194 863 140 190
8 2.4 6.4 0.58 — — 400 1780 288 390
10 3 8.05 0.72 — — 503 2238 362 491
12 3.8 12.71 1.14 — — 761 3386 697 945
15 4.6 24.5 2.21 — — 1531 6813 1404 1904
1000 -2700 MHz / 0 – 180° Angle / Without Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 2.24 0.2 140 623 — — 55 75
4 1.2 6.32 0.57 395 1758 — — 181 245
6 1.8 11.22 1.01 701 3119 — — 409 555
8 2.4 19 1.71 1188 5287 — — 693 940
10 3 27.43 2.47 1714 7627 — — 1000 1356
12 3.8 46.87 4.22 2929 13034 — — 1709 2317
15 4.6 79.72 7.17 4983 22174 — — 2906 3940
1000 -2700 MHz / 90° Angle / Without Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 0.68 0.06 — — 43 191 25 34
4 1.2 2.35 0.21 — — 147 654 106 144
6 1.8 4.84 0.44 — — 303 1348 218 296
8 2.4 8.39 0.76 — — 524 2332 377 511
10 3 10.15 0.91 — — 634 2821 459 622
12 3.8 15.71 1.41 — — 982 4370 900 1220
15 4.6 30 2.7 — — 1875 8344 1719 2331
1000 -2700 MHz / 0 – 180° Angle / With 1/2″ Radial Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 6.4 0.58 400 1780 — — 158 214
4 1.2 11.82 1.06 739 3289 — — 339 460
6 1.8 23 2.07 1438 6399 — — 839 1138
8 2.4 39.43 3.55 2464 10965 — — 1438 1950
10 3 59.83 5.38 3739 16639 — — 2181 2960
12 3.8 90.57 8.15 5661 25191 — — 3302 4477
15 4.6 146.6 13.19 9163 40775 — — 5345 7247
1000 -2700 MHz / 90° Angle / With 1/2″ Radial Ice
Diameter A FA FS M
ft. m sq. ft. sq. m lbs N lbs N ft-lbs N-m
3 0.9 1.49 0.13 — — 93 414 54 73
4 1.2 2.61 0.23 — — 163 725 117 159
6 1.8 5.77 0.52 — — 361 1606 259 351
8 2.4 10.2 0.92 — — 638 2839 458 621
10 3 15.38 1.38 — — 961 4276 691 937
12 3.8 22.33 2.01 — — 1396 6212 1279 1734
15 4.6 35.98 3.24 — — 2249 10008 2061 2794