First, blood given pre-hospital is quite routine these days. Both ambulances and helicopters are carrying Low Titer O Positive whole blood that they transfuse on scene in response to traumas and hemorrhagic shock. In South Texas, the ambulances and helicopters receive their blood directly from our blood supplier. Who will be stocking your helicopter? Will it be your facility? If so, you have a lot of work to do. If your supplier, you have nothing to fear.
Second, when a unit is given pre-hospital, our EMS techs give the empty blood bag and a record of transfusion to the receiving nurse in the Emergency room, who then sends them to the blood bank (theoretically, practically we seldom get them right away). Our emergency room physician orders a type and screen upon arrival. Only if an antibody is detected (or we have a history of a clinically significant antibody) will we perform any crossmatching with the unit.
I would suggest you google the topic Low Titer Whole Blood. It will help you answer your question.