Man that's rough. I've lost a few good friends in the aviation industry and I always found myself asking how, or why. Great people, fly by the book, but things still happen.
God Bless your friends and prayers to the family. I can't imagine what they must be going through.
My dad (Army Air Corp/Air Force) always taught me to show complete respect towards our military because they are the ones making the sacrifices so that we can be safe. Lately the wars have been pushed to the back as if people have forgotten that we still have men and women serving overseas.
I encourage everyone to check out the Military Channel shows "Ultimate Warfare" about Sperwan Ghar, and National Geographics "Inside Combat Rescue." They are hard to watch but you'll get a better appreciation for what they are doing over there. http://military.discovery.com/tv-shows/ultimate-warfarehttp://channel.nationalgeographic.com/channel/inside-combat-rescue/
Animal Planet has a great show too that I recommend everyone watch. Like it says on the site, "It will warm and break your heart." http://www.miamiherald.com/2013/02/21/3243869/documentary-about-dogs-at-war.html
Being in the military is a high risk job and I for one appreciate all that they do, and that they give for their country. I will keep them in my prayers, and thanks for letting us know.