be on a collision course

Of a person, group, or object, to be on a certain path to conflict, collision, destruction, or ruin with someone or something else. The radical coalition is set to be on a collision course with the majority government this year. Little did the passengers know that their train was on a collision course with disaster. With all those lies that jerk has told, he's on a collision course with disaster—just sit back and enjoy the ride!

be on a colˈlision course (with somebody/something)

1 be in a situation which is almost certain to cause a disagreement or dispute: I was on a collision course with my boss over the sales figures.
2 be moving in a direction in which it is likely that you will crash into somebody/something: The ship was on a collision course with a huge iceberg.