A forced off-airport landing is not a necessarily crash. It’s an action taken, usually because of engine failure or imminent engine failure, to mitigate risk to the occupants of the craft. The pilot acts with intention and glides or flys the craft to the ground. They slow the craft down enough to touch down safely. The incident could still be considered an accident if there’s damage to the structure of the plane or injury to passengers.

In contrast, a crash could be a lot of things: two planes colliding on the tarmac, loss of wings, or a controlled flight into terrain (such as flying into the side of a mountain).