Fall Factor and Impact force Calculations

Hello All 

I am attempting to mathematically define both fall factor and impact force while using static rope (rescue rope) and top anchors both with and without an AHD/HD?

The accepted calculations for both are based upon utilizing dynamic rope and climbing above an anchor. In the rope rescue world this practice is not acceptable unless it is tower rescue work. 

Does anyone have a good source of information that I can use?

you should be able to search the ITRS online tech papers for research results on system testing. 

https://itrsonline.org/

You won't be able to assume that it's completely unstretchable - that'll result in an infinite force to stop the load instantly. It's a matter of degree; the static rope just has a higher effective spring constant than the dynamic rope, but the physics is the same.

If you really want the math: rgold's analysis

AFAIK fall factor is always defined as the fall length divided by the length of rope used to catch the fall, regardless of the anchor position.  As Josh Gates says, to get the impact force you'll need to know how much the static rope actually stretches.  Manufacturers may give you clues, e.g. elongation of around 3% for a Bluewater static rope under a static load.