Under the Bridge

[TommyK154]

So I started a few bridges before I started keeping track, but now I am keeping track and when I fly under a bridge and I don't get a pop up idk if its because I got it already or because I didn't do it correctly. Im 48/50 I just need to find 2 more,and I have it narrowed down to the ones before I started keeping track but I re-did all of them. If I fly under a bridge and the helicopters rotors hit the wall or something does it not count? Because some of the spaces are just way too small to not hit anything. Because idk if I'm not getting it because I already got it or because I'm doing it wrong. Haaalp