So there I was... onboard USS Topeka (SSN 754) in November 1992, where the boat had just pulled into Mina Salman, Bahrain, for a mid-deployment upkeep. Before we could go out on liberty, however, we had a few items to take care of. I was responsible for making sure that a couple hundred packages got signed over to the Defense Courier Service from the "special" mission we'd been doing -- the tender guys and gals couldn't come on board to start the upkeep until it was all gone.
I had inventoried everything the night before, and rounded up a working party of about 8 guys to get all the packages moved out to the government van; I checked off the items on the inventory list with the local DCS rep as they were loaded in. When the guys brought out the last load, every block was checked... except one. That caused a little bit of excitement as we ransacked all the places these items had been kept, and after about a half hour we found the package (a 9 x 12 inch envelope); it had fallen behind a bench in Radio. I breathed a huge sigh of relief and headed off to the Alcohol Support Unit at the base to start to unwind from being so vital to national security over the previous several weeks, in preparation for heading out into town to see what Manama had to offer.
Anyone care to share their favorite "Aw, crap" moment?
Update 1155 08 September: Going back through my archives, here's a story that falls under the category of "Stupid JO Tricks" more than "AwCrap". And as a "bell-ringer" (moving a link from the comments up to the main story) here's the story of the CO of USS The Sullivans (DDG 68) becoming the 18th Navy Commanding Officer fired this year for mistakenly targeting a civilian fishing vessel with inert training rounds during deployment workup.