For several years, safety experts have been concerned about collision hazards near O'Hare and the abnormally high number of incidents there.

Installation of the equipment in the planes was ordered by the aviation agency two years ago after decades of studying collision hazards.

The private pilots have argued in their lawsuit, which is still pending, that closing the corridor has increased, not decreased, the collision hazard.

They add a larger terrain obstacle and collision hazard.

The improvements are designed to widen bridges and create significantly more merging space so that collision hazards are mitigated.

The collision hazard has been highlighted in particular by two dramatic close calls.

The existence of interplanetary collision hazards, when widely understood, works to bring our species together.

The spaceships are a collision hazard and normally fly around the screen randomly.

They argued that it had increased, not decreased, the collision hazard.

These pose a collision hazard in the narrow and shallow strait.