I am curious where you got your information of 15 yards from the vehicle. I did not see that detail either in the article or the referenced news report from Tucson News 4. Perhaps you have some other link or source that you can share with us?
What I did see in the article is that the helicopter crossed only 100 yards (300 feet) into US territory. That is just a second or two at 80 mph.
How do you know it was going 80? Not 50 or 35?
I got the link from another thread on the same subject.
http://www.freerepublic.com/focus/f-news/3173052/posts?q=1&;page=101