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

WWW.SURVIVALEBOOKS.COMFor example, in theory a vehicle (5) Streambed and depth. For fordingtraveling at six kiloireters per houroperations, the depth of the water obina stream that has a currentstacle and the bottom conditions mustspeed of six kilometers per hour andbe determined. Field expedients areis 100 meters across will land 100used for determining depths sincemeters downstream from the pointthere are no mechanical devices orwhereit entered the water. Sinceganic to armor units. These includethere is an unknown component ofmeasured poles, weighted measuredthe vehicle speed moving the vehi- ropes, and similar devices. Depthcle, the landing point will be morereadings should be taken every ninethan 100 meters downstream (fig.feet. Bottom conditions are deter-28). This formula gives a rough es- mined by getting into the water andtimate of the landing point. An ad-checking the stability and composiditionaldistance downstream willtion of the bed. If the water is shalalwaysbe required because of thelow, this can be accomplished by waddownstreamcomponent of the vehi-ing across the obstacle. In deepercle's speed (in addition to stream water, underwater reconnaissancespeed), consequently, the only satis-personnel or other means will have tofactory means to determine the ex-be used to determine bottom condiactlanding point is a trial crossing.tions.(d) Maximum water speeds of vehicles e. Underwater Reconnaissance.are found in appropriate operator (1) If underwater reconnaissance personandtechnical manuals.nel are provided, they are utilized toFAR BANKDOWNSTREAM DRIFTlOOmUNKNOWTHEORETICAL EXIT A TEr ~ ~ ~ ~ ~ n , ACTUAL EXITDIRECTION OF CURRENT_CURRENT (6 KMPH) 04 MASMALL ANGLE IN DIRECTION OF CURRENTENTRANCE(NEAR BANK)(BOW OF APC HEADED AT SMALL ANGLE DOWNSTREAM)Figure 28. Doumstream drift in a stream crossing.189