and in 1988 the a-320 launched and right away manufactures sold and it has been the fastest selling plane in the world and so you can imagine how many take off in a daily basis but you have a handful of these incidents so awful to hear about, including the one that happened today. indeed. awful to have that context. frances, thank you. we appreciate it. and let s bring in christine dennison founder of mad doing expedition and investigate yoror dan five. and obviously this debris field spread across the french alps. a wide debris field. how does that complicate things? it is tragic. you have very difficult terrain. and bad weather hampering it.