Open heights. Planes are fine, and as long as I have a decent railing I'm okay, but I can't do roller coasters, high dives (even 10 footers scare the piss out of me), excessively large trampolines (like the ones at carnivals), and I can do log rides and somewhat large slides, but those are still pretty troubling for me.
Maybe it doesn't qualify as a full-on phobia, but it sure made boot camp hell. The Navy requires you do a 20-30 foot jump from a high dive... needless to say, I just closed my eyes and let them push me. I think that was the only time in my entire life where my mind was literally completely blank with fear. Absolutely no thoughts were in my head for those 2 seconds.
Maybe it doesn't qualify as a full-on phobia, but it sure made boot camp hell. The Navy requires you do a 20-30 foot jump from a high dive... needless to say, I just closed my eyes and let them push me. I think that was the only time in my entire life where my mind was literally completely blank with fear. Absolutely no thoughts were in my head for those 2 seconds.