A bomb on board an airliner has an altitude-sensitive trigger. Unless a ransom is paid, it will explode when the plane descends to land.A bomb on board an airliner has an altitude-sensitive trigger. Unless a ransom is paid, it will explode when the plane descends to land.A bomb on board an airliner has an altitude-sensitive trigger. Unless a ransom is paid, it will explode when the plane descends to land.