effects of size and speed on model airplane crashes

I am looking for an equation that correlates material failure and collision speed;

so that I can better understand the effects of size and speed on model airplane crashes.



Is there an equation that correlates an object's length and speed to material failure,

for one-dimensional elastic collision of into a rigid barrier,

given elastic modulus and specific strength?



This is a guess:

specific strength :: speed^2 * length

but it's probably more complicated than that.



Thank you.