Friendly Fire

[Cross-posted from my Burning Questions series on Bound by Gravity]

The latest friendly fire incident in Afghanistan has brought the expected reaction from some quarters, and it is difficult to blame them. With that in mind I would really love to know:

1. How many incidences of friendly fire have occurred in the Afghanistan war?
2. How many times has air support been called for and delivered in the Afghanistan war?
3. Is there a militarily accepted/expected ratio for friendly fire? [Keeping in mind that (a) we NEVER want friendly fire to occur, and (b) friendly fire is an inevitability of modern warfare.]
4. How does the ratio of air support to friendly fire in the Afghanistan conflict compare with previous wars?
5. Do some nations who provide air support have a statistically higher ratio of friendly fire mistakes than others?
6. Are some nations statistically more likely to be the victims of friendly fire?

Note: I'm only dealing with friendly fire from air support at the moment - there are obviously other ways it can occur.


If you can provide answers to any or all of these questions, I would greatly appreciate it.