From Longman Dictionary of Contemporary Englishbe on a collision coursebe on a collision coursea) DISAGREEto be likely to have serious trouble because your aims are very different from someone else’s The two nations are on a collision course that could lead to war. b) HIT/BUMP INTOto be moving in a direction in which you will hit something an asteroid on a collision course with Earth → collision
Examples from the Corpus
be on a collision course• Newspaper reports say that the two nations are on a collision course that could lead to war.• It needed no great powers of prophecy to realize that Nigel and I were on a collision course.• Nurses lodge 10 Nurses are on a collision course with the Government after lodging a claim for a ten percent pay rise.• Suddenly I found that he and I were on a collision course, both in Atlas aircraft.• The Croatan was on a collision course with the twenty-foot branch and its two passengers.• Union leaders representing more than 8,000 white-collar staff gave warning of more stoppages and said the company was on a collision course. 