Similar situation happened to me once when I owned a C5 vette. It was almost comical (at least now it is), scary, and shameful all at the same time. It is strange how the Targa/T top will not give you any notification of not being latched until you hit 60 and it is instantly gone...woof. Luckily, no one was behind me like yourself, so I thought it might still be salvageable, until what happened next. I was running back up the highway to retrieve it when I saw this van approaching. Thinking that they would run it over, I was probably running like an idiot and freaking out trying to get to the top before they got too close and pointing at it so they wouldn't hit it. Well, the van must have thought I was a little special and decided it wanted to be as far away from me as possible. It swirved away from me and it just so happens that was the lane my top was in and BAM...bye bye top. I had to buy a new one. Ouch! I guess it was a lesson for me to never debate with the wife when you are trying to do something to your car. Oh well, no big deal just pay your deductible and turn it in to insurance. I was too embarrassed to tell anybody for a while though.