Not all the time spent on a rescue boat is actually rescue work. The majority of time spent on the boats is training. One method of training we were once given was actually pretty unorthodox, but related to an actual search pattern.
One of the trainers decided the best way to get a fair idea in searching for somebody would be to release a tennis ball and go find it. Simple? No it isn’t actually.
First we went out into the ocean and watched where the wind and current moved us to for 10 minutes. After that we calculated the drift and the speed of the current. Do not worry there is a formula for this. After releasing the tennis ball out in the ocean, we went back to shore to have a coffee and food.
Half hour later we were back on the water, looking for the drifting tennis ball. The ocean is a big place and the trainer expected us to find the ball. All crew members were keeping a look out for a small tennis ball. After a while the tennis ball was spotted. There was also one problem. A whale was close to the ball and it wasn’t moving much. In our search, we had actually nearly ran the whale over. We picked up the tennis ball and headed back home. The trainer was impressed as the ball had been found exactly where he thought it would be.
Later on, while discussing about the lethargic whale, we got our answer. The whale was actually giving birth. None of us at the time knew this, but the story is we found a whale near our tennis ball.
Distance = Speed x Time
The formulas do get complex after time. Today we just use the GPS to co ordinate our searches.