What is the ruling on one who accidentally kills a Muslim in a traffic accident, and is it permissible for him to break his fast during the two consecutive months of fasting if he travels daily a distance exceeding 120 kilometers and is unable to fast in this situation?

There are three types of expiation for killing, in sequential order: If you are unable to free a slave, then you must fast for two consecutive months. If you are permanently unable to fast, then expiation by feeding is permissible. However, permanent travel is not a permanent inability to fast; rather, it is a temporary inability, and therefore does not justify moving on to feeding.