name your C130 air

place the group in the cargo positions by using the code below in the leaders init

blue=group this;{_x moveincargo air} foreach units blue

blue will be the name of the group and the plane is just called air. You change the names as you wish.

Place a trigger of size 10,10 wher you want the plane to stop and group it to the c130 make sure the trigger is set to present and in the condition put this

this and getposATL air select 2 < 1

It checks that the c130 not flying or at least only a meter above the ground.

Place this in the triggers on act box

null = [] spawn {air setfuel 0;air animate ["door_1", 1];sleep 4;{unassignVehicle _x;_x action ["eject",air] ;sleep 0.5} foreach units blue};

it removes the fuel opens the door and ejects group blue from the plane.