Shock factor

<p>Shock factor is a commonly used <a href="/facts/Figure_of_merit/kdSJ3Cpy">figure of merit</a> for estimating the amount of shock experienced by a naval target from an <a href="/facts/Underwater_explosion/NppW55Fw">underwater explosion</a> as a function of  explosive charge weight, <a href="/facts/Slant_range/tcfaYtuu">slant range</a>, and depression angle (between vessel and charge). 
</p><p>
  
    
      
        S
        F
        =
        
          
            
              W
            
            R
          
        
        
          
            
              (
              1
              +
              sin
              ⁡
              ϕ
              )
            
            2
          
        
      
    
    {\displaystyle SF={\frac {\sqrt {W}}{R}}{{(1+\sin \phi )} \over 2}}

</p>
<ul><li><i>R</i> is the slant range in feet</li>
<li><i>W</i> is the equivalent <a href="/facts/TNT/sADUt6nC">TNT</a> charge weight in pounds = charge weight (lbs) · <a href="/facts/Relative_effectiveness/nEQ5z8mp">Relative effectiveness factor</a></li>
<li>
  
    
      
        ϕ
      
    
    {\displaystyle \phi }
  
 is the depression angle between the hull and <a href="/facts/Warhead/DKJ7lyqb">warhead</a>.</li></ul>
<p>The application scenario for Equation 1 is illustrated by Figure 1.
</p>
<table><tbody><tr><th></th><th></th></tr><tr><td></td><td></td></tr><tr><td></td><td>Figure 1: Shock Factor Application Scenario.</td></tr></tbody></table>
<p>The numeric result from computing the shock factor has no physical meaning, but it does provide a value that can be used to estimate the effect of an underwater blast on a vessel. Table 1 describes the effect of an explosion on a vessel for a range of shock factors.
</p>
  Table 1: Shock Factor Table of Effects <table><tbody><tr><th>Shock Factor</th><th>Damage</th></tr><tr><th>< 0.1</th><td>Very limited damage. Generally considered insignificant</td></tr><tr><th>0.1–0.15</th><td>Lighting failures; electrical failures; some pipe leaks; pipe ruptures possible</td></tr><tr><th>0.15–0.20</th><td>Increase in occurrence of damage above; pipe rupture likely; machinery failures</td></tr><tr><th>0.2</th><td>General machinery damage</td></tr><tr><th>≥ 0.5</th><td>Usually considered lethal to a ship</td></tr></tbody></table>

Shock factor open-in-new

Shock factor