1966 US Army Vietnam War ARMOR ... - Survival Books

WWW.SURVIVALEBOOKS.COMCENTERLINEI- CLOUD TOPi'CLOUDIDIAMETERT91sg'\!D\CLOUD BOTTOM \STEM )-vHORIZONTAL)GROUND ZERO OBSERVER CLOUD TOP ANGLE OBSERVERCLOUD DIAMETER (MILS) (MILS) CLOUD BOTTOM ANGLE (MILS)Figure 100.Cloud measurements.(1) Primary. Every effort should be made determine ground zero. Readings of elevationto obtain the following:to the intersection of the stem and cloud bot-(a) Height of the bottom of the cloud tom, elevation to the top of the cloud, and the(intersection of the stem and bot- azimuths to the edges of the cloud at its widesttom of the cloud) at the time it points are taken at 10 minutes after detonareachesits maximum altitude (ap- tion. In the absence of instruments, individualsproximately 10 minutes after deto- will use field expedient methods for determinnation)(fig. 100).ing these measurements. Information outlined(b) Ground zero location (by intersect- is submitted to the next higher headquartersing azimuths, flash-bang-time, by the most expeditious means.sound ranging, or radar).(2) Secondary. Efforts should be directed 6. Field Expedient Measurement of Anglestoward measuring the following pa- When optical instruments are not availablerameters in addition to the height of for measurement of angles required for the dethebottom of the cloud:(a) Height of the top of cloud at the termination of burst parameters, these anglestime it reaches its maximum alti- can be estimated in mils through field expetude(approximately 10 minutesafter detonation) (fig. 100).dients. This is accomplished by the observerholding his arm fully extended and measuring(b) Cloud diameter at 10 minutes after the angle in terms of a number of fingers (30detonation (fig. 100).mils each), or fist (180 mils), or fingers spread(c) Height of burst-whether an obvi- (300 mils), as described in FM 3-12.ous airburst or surface burst.b. All units with optical equipment will7. Nuclear Burst Sighting Reportorient their instruments on the site of the The format for transmission of nuclearburst. A reading to the center of the stem is burst measurements is contained in appendixtaken as soon as feasible after detonation to V.399