ACCIDENT DYNAMICS RESEARCH CENTER

PO BOX 261, UNCASVILLE, CT 06382

 

SPEED CALCULATION CHART

1st: Find Distance that the vehicle accelerated or decelerated( 1st vertical column).  2nd: Find the impact speed (or the initial speed if accelerating)(2nd vertical column); 3rd: Go across that row until you reach the column with the frictional coefficient that you would like to use.  There are several factors (that have not been considered) that may go into a speed calculation, so these results must be used with caution.  The circumstances listed do not fit every occasion, therefore, this chart shows no more than a "Thumb-in-the-air" estimate and the chart itself does not have scientific validity.
      1 FR or rear only 2 FR brakes out 2 Rear Brakes out 1 FR brake out 1 Rear brake out      
    Car Passing Acceleration Car Acceleration from Stop Motorcycle 

Tractor

 acceleration

trailer

 f/ stop

braking

      
     Engine

 braking

 Routine braking Box Truck Milled Road      
      Yaw MC rear only Garbage Tr        
    Ice Snow Snow Wet Wet steeply down Dry Dry new Cement dry
      Bobtail Dump/tanker        
    Truck acceleration from stop   Motorcycle/Vehicle sliding on side        
Distance Impact Speed 0.1 0.2 0.3 0.4

0.5

 0.6 0.7 0.8 0.9
10 0 5.5 7.7 9.5 11.0 12.2 13.4 14.5 15.5 16.4
10 10 11.4 12.6 13.8 14.8 15.8 16.7 17.6 18.4 19.2
10 20 20.7 21.4 22.1 22.8 23.5 24.1 24.7 25.3 25.9
10 30 30.5 31.0 31.5 31.9 32.4 32.9 33.3 33.8 34.2
10 40 40.4 40.7 41.1 41.5 41.8 42.2 42.5 42.9 43.2
20 0 7.7 11.0 13.4 15.5 17.3 19.0 20.5 21.9 23.2
20 10 12.6 14.8 16.7 18.4 20.0 21.4 22.8 24.1 25.3
20 20 21.4 22.8 24.1 25.3 26.5 27.6 28.6 29.7 30.7
20 30 31.0 31.9 32.9 33.8 34.6 35.5 36.3 37.1 37.9
20 40 40.7 41.5 42.2 42.9 43.6 44.3 44.9 45.6 46.3
Distance Impact Speed 0.1 0.2 0.3 0.4

0.5

 0.6 0.7 0.8 0.9
30 0 9.5 13.4 16.4 19.0 21.2 23.2 25.1 26.8 28.5
30 10 13.8 16.7 19.2 21.4 23.5 25.3 27.0 28.6 30.2
30 20 22.1 24.1 25.9 27.6 29.2 30.7 32.1 33.5 34.8
30 30 31.5 32.9 34.2 35.5 36.7 37.9 39.1 40.2 41.4
30 40 41.1 42.2 43.2 44.3 45.3 46.3 47.2 48.2 49.1
40 0 11.0 15.5 19.0 21.9 24.5 26.8 29.0 31.0 32.9
40 10 14.8 18.4 21.4 24.1 26.5 28.6 30.7 32.6 34.4
40 20 22.8 25.3 27.6 29.7 31.6 33.5 35.2 36.9 38.5
40 30 31.9 33.8 35.5 37.1 38.7 40.2 41.7 43.1 44.5
40 40 41.5 42.9 44.3 45.6 46.9 48.2 49.4 50.6 51.8
50 0 12.2 17.3 21.2 24.5 27.4 30.0 32.4 34.6 36.7
50 10 15.8 20.0 23.5 26.5 29.2 31.6 33.9 36.1 38.1
50 20 23.5 26.5 29.2 31.6 33.9 36.1 38.1 40.0 41.8
50 30 32.4 34.6 36.7 38.7 40.6 42.4 44.2 45.8 47.4
50 40 41.8 43.6 45.3 46.9 48.5 50.0 51.5 52.9 54.3
Distance Impact Speed 0.1 0.2 0.3 0.4

0.5

 0.6 0.7 0.8 0.9
60 0 13.4 19.0 23.2 26.8 30.0 32.9 35.5 37.9 40.2
60 10 16.7 21.4 25.3 28.6 31.6 34.4 36.9 39.2 41.5
60 20 24.1 27.6 30.7 33.5 36.1 38.5 40.7 42.9 44.9
60 30 32.9 35.5 37.9 40.2 42.4 44.5 46.5 48.4 50.2
60 40 42.2 44.3 46.3 48.2 50.0 51.8 53.5 55.1 56.7
70 0 14.5 20.5 25.1 29.0 32.4 35.5 38.3 41.0 43.5
70 10 17.6 22.8 27.0 30.7 33.9 36.9 39.6 42.2 44.6
70 20 24.7 28.6 32.1 35.2 38.1 40.7 43.2 45.6 47.9
70 30 33.3 36.3 39.1 41.7 44.2 46.5 48.7 50.8 52.8
70 40 42.5 44.9 47.2 49.4 51.5 53.5 55.4 57.3 59.1
80 0 15.5 21.9 26.8 31.0 34.6 37.9 41.0 43.8 46.5
80 10 18.4 24.1 28.6 32.6 36.1 29.2 42.2 44.9 47.5
80 20 25.3 29.7 33.5 36.9 40.0 42.9 45.6 48.2 50.6
80 30 33.8 37.1 40.2 43.1 45.8 48.4 50.8 53.1 55.3
80 40 42.9 45.6 48.2 50.6 52.9 55.1 57.3 59.3 61.3
Distance Impact Speed 0.1 0.2 0.3 0.4

0.5

 0.6 0.7 0.8 0.9
90 0 16.4 23.2 28.5 32.9 36.7 40.2 43.5 46.5 49.3
90 10 19.2 25.3 30.2 34.4 38.1 41.5 44.6 47.5