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Accident Reconstruction Calculators

Below are some basic accident reconstruction tools. They should be used to estimate ranges of answers for common reconstruction calculations. Most problems involves more complicated factors so make sure to consult an Automotive Engineer. 

Distance Traveled During Perception & Reaction time

This equation is used to estimate the distance a vehicle travels during the time it takes the driver to perceive and react to an impending hazard. The normally accepted range of Perception and Reaction time is 1 and 1.5 seconds. If this occurs for instance before braking, then the Perception of Reaction distance must be added to the braking distance. 


Distance = Speed x Time

And with a conversion factor: 

D = (1.467 x S x T)


D = Distance Traveled (feet)
1.467 = Conversion factor (converts mph to fps)
S = Speed (mph)
T = Time (in intervals of 1 second) 

Example Calculation:

Vehicle 1 was traveling at 65mph when a deer ran across the highway. How far did the vehicle travel before the driver was able to begin braking? 

@ 1 Sec.: D = (1.467 x 65 x 1) = 95 feet

@ 1.25 Sec.: D = (1.467 x 65 1.25) = 119 feet

@ 1.5 Sec.: D = (1.467 x 65 x 1.5) = 143 feet

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