I was on the Oleander on it's first trip to the far east. As the ship was slowing down to turn into the stores basin at Singapore Dockyard a taper pin fell out of the astern main steam valve spindle. As some fool had fitted the pin inside the bulkhead of the control room nobody knew what had happened, apart from the fact that the 3rd Engineer was opening the valve and nothing was happening.
We smashed one tug against a boom defense vessel and another against the Fearless. Luckily, the tugs managed to hold us, and we stopped no more than 10 feet astern of the Leander class frigate Cleopatra, who we would have cut in half.
I was in the MCR at the time and found the experience somewhat worrying, espeacially when the Chief Electrician started praying.