On holiday last week. we had an unfortunate accident. Our aqua roll bar managed to drop through the vent holes in the front box vertically creating a large hole under the caravan as we reversed onto our pitch. The caravan repairers say they have never heard of this happening before am I just unlucky. What can anyone suggest that I should do to prevent this happening again. My friends fill their front box thus preventing movement of small narrow objects but my towcar will not allow me to fill my front box. Any help please.