on a collision course

on a collision course

Of a person, group, or object, on a certain path to conflict, collision, destruction, or ruin with someone or something else. The radical left-wing coalition is set to be on a collision course with the majority conservative government this January. Little did the passengers know that they were riding a train on a collision course with disaster.
See also: collision, course, on
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

on a collision course

adopting an approach that is certain to lead to conflict with another person or group.
This phrase is also used literally to mean ‘going in a direction that will lead to a violent crash with another moving object or person’.
See also: collision, course, on
Farlex Partner Idioms Dictionary © Farlex 2017
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References in periodicals archive ?
It said both vessels were on a collision course and the navigation rules required the Sanchi to make way.
They were set to walk out on the day Cardiff council's new food waste collections were due to start - a scheme which had set workers and bosses on a collision course.
These pristine fragments could reveal how easily an asteroid breaks apart and whether a space rock on a collision course with Earth could be destroyed by a nuclear blast.
Reports suggest that the crew of the Russian aircraft informed Swiss air traffic controllers that they were on a collision course with another aircraft 90 seconds before impact.
A Boston newspaper, reporting on the cause of a collision between a Coast Guard cutter and a freighter, quoted the USCG finding that the cutter's skipper "did not comprehend that the vessels were in a meeting situation...." Whatever happened to dependable on a collision course? What's wrong with about to collide?