Impact Angles
The pictures below are from an experiment showing the various stain patterns produced from blood drops hitting a target surface at various angles. The tails that you see on the stains indicate the direction of travel. By determining the true ellipse and measuring its width (short axis) and length (long axis), one can determine its approximate
impact angle. When blood drops hit a surface at other than a 90 degree angle, the stain will appear more elongated. One of the questions the analyst may be posed with is whether the victim was laying down, kneeling, sitting or standing. By determining impact angles, areas of convergence and origin, the analyst can answer that question. Information such as this can collaborate or refute a statement from a witness or suspect. Here you can
download an exercise to practice measuring stains.
10 Degree Impact Angle 20 Degree Impact Angle
30 Degree Impact Angle 40 Degree Impact Angle
50 Degree Impact Angle 60 Degree Impact Angle
70 Degree Impact Angle 80 Degree Impact Angle
90 Degree Impact Angle
