predictors and a nomogram for determining the downwind distance of Zone I.
One simplified predictor is drawn to a scale of 1:50,000, with five
preselected yield groups (A, B, C, D, E); and one predictor is drawn to a
scale of 1:250,000, with six preselected yield groups (A, B, C, D, E, F).
It may be requisitioned through supply channels using FSN 6665-106-9595.
Each simplified predictor consists of three major parts:
a. An azimuth dial for orientation.
b. Semicircles depicting stabilized nuclear cloud radii drawn about
ground zero and sh@ing the area of contamination for each of the preselected
c. A map scale calibrated in kilometers along two radial
extending out from the center of the azimuth dial, fixed at 400.
d. The nomogram (Figure 3-14), consisting of three scales, is
positioned between the radial lines of the M5A2 Radiological Fallout Area
Predictor and is used to determine the downwind distance of Zone I.
nomogram is not required for field constructed predictors.
(1) The left-hand scale is the effective wind speed in kilometers per
(3) The right-hand scale is the yield in kilotons.
Procedures for Use of Simplified Method.
effective downwind message, an actual or estimated yield of the nuclear
weapon detonated, and location of ground zero.
Normally, the user of the
M5A2 will have to obtain the yield and the location of ground zero from
measured data or from the NBC 2 (Nuclear) Report.