I heard they only took a month to do. As a Crypto/Intel/Sub guy in OCS you can't commission w/o it, that's what we were told anyway. As a pilot they may take 1.5 years to get around to it? Clearence isn't really a priority for flight students I imagine, especially when you can separate from the program and go somewhere where it's not required. I do remember hearing it costs the US around 35k in manhours and travel expenses to do one.