Thats why I made a PCV tube with a sealable end, and put it inside my Camper shell.Sucks!
A buddy of mine lost an expensive set-up on the freeway from the back of his truck. I felt horrible cause I was the one that made/gave him the rod covers. The wind easily catches those plastic type electrical mesh covers even with the tip pointing to the tailgate (especially light composite rods). If you use those type of covers and travel with unbundled rods (on the freeway or at good speeds on the water), learn from our mistake and bundle/tie them down.
I liked and still use the covers, so I made a couple of lengths of para cord, tied small ss clips on each end. Easy and fast to wrap/cinch around the protected rod bundle and clip to truckbed or T-top post. We also use them for troller/kite rod safety lanyards to maximize their value.
Since then... I find myself looking for rods on the 1.5 hour freeway commute from my house to San Diego on fishing days.