Yes, there has been an incident, where French control at Ottawa of a landing Metro landed (or overshot , cant remember now) overtop of a positioned AC regional jet. The regional jet pilot was cleared to position to hold and a Metro had to overshoot. The RJ captain reported that the Metro was being handled in French and that he had no idea what was happening. The TSB investigators cited bilingual control of the aircraft as a contributing cause of the incident however that finding was dismissed by the higher up politically correctors.