An unexpected journey to the seabed.
When Gandalf the Grey was struck by the Barlog and fell into the depths of the mountain at the bridge of Khazad dum, the Fellowship despaired. They had lost and old friend and their guide. When the underwater robot Harald did not return to the surface after a routine mission, the scientists on board the R/V Kronprins Haakon despaired. After some maneuvering, acoustic ranging, and trigonometry (yes, it is useful outside a high school classroom) the scientists concluded that the robot was stuck on the seabed, at bone-crushing 300 meters below the surface. The underwater craft is made to withstand the pressure found at 100 meters depth, and it was now stuck at 300 meters, experiencing forces three times greater than what it was made for. Time was of the essence.
The scientists knew the position of Harald, due to the aforementioned math, but had no way of getting to 300 meters and rescue it. The only candidate was a small 9 kilogram ROV, made to go down to 150 meters and also having a cable to the surface, winch was also 150 meters long. The scientists held a council and it was decided to send the small ROV to the seabed, carrying a rope to hook on to Harald. A 500 meter cable was made, forged from the remains of a 20 year old cable belonging to a Microstructure Sesnor, and soldered together in the fires of the Fine Electronics workshop. With the ROV tethered to a weight for the winch to lower down into the icy depths and the cable fully operational, the operation was ready to begin, scientists and crew alike gathered in the hangar to observe. At this time it was 16 hours since last contact with Harald.
The ROV and the weight was lowered down and the rescue operation was underway. Slowly descending, the scientists watched the depth-measurements in silence. 50 meters … 100 meters ... 120 meters … and when the ROV was at 120 meters, the bridge called over the radio: “Yes, hello, you don’t happen to have a red blinker on this Harald?” They had spotted something in the surface. The operation suddenly stopped and the scientists rushed to see if there was any satellite traffic from the lost robot. There was. 20 minutes later, Harald was back on board. The scientists breathed a sigh of relief and wondered over their incredible luck.
After some investigation, it was reviled that the robot had dived nose first into the soft mud of the Barents Seabed and was stuck there until the current wiggled it loose. The robot is now known as Harald the White.