After having completed the required training, we were free to spend our remaining time playing in the surf zone. The Columbia River offers a very unique training environment for surf. The worst of it is to the north of the river entrance at Peacock Spit. We observed the surf conditions there during our first week. Because of the bottom characteristics in that area, there tends to be three different "sets", that is to say the breaking waves come in simultaneously from three directions. A key element to maneuvering in surf is "squaring up" where you keep you bow aimed directly into the waves. This is a difficult task when you surf out of just one direction, which is why we didn't conduct training at Peacock Spit.
Instead, we trained right inside the river entrance where the conditions were challenging but better suited for trainees. There were three different concepts we covered on the first day in the surf that would be the main focus of our remaining time at Cape D:
We would start at the end of the surf zone and work our way out into it using an "outbound" or an "up-swell run". We would come up to full power and then use helm adjustments and throttle management to negotiate our way through the breakers. The two main things were to not take the boat through a wave as it broke and to not get the boat airborne. The saying is "if it looks like a ramp, it is a ramp."
When we had to move perpendicular to the surf we used a "lateral run". Basically the same idea as the outbounds. We would make full speed and then judge the incoming breakers to see which ones we could pass in front of and which ones we had to allow to pass by before we kept going.
The most difficult of the three was the down-swell run. As waves interact with the ocean bottom and start to break, they also slow down. This allows the MLB to outrun or keep pace with the waves, something that isn't possible on the open ocean. Although the 47' accelerates fairly well, it never seems like enough when a twenty foot breaker is bearing down on the stern. If a breaker does catch up and passes underneath the boat, there is a very good change that the boat will be knocked down, rolled, or even worse, pitch-polled (tumbling end over end).
On our second or third day in the surf, I was coming of a lateral run and then transitioned to a down-swell run. As my bow lined up to run with the seas, I threw both throttles in full ahead. There's a long list of things to monitor while running down-swell. I was continually looking over my shoulder to find the next breaker. Is it gaining on me? Is it starting to break? Then I would check again in front of us. If you catch up to wave in front of you, you can bury the bow, or even climb up and over, plunging down in front of it violently. If the wave you're following starts to break, it leaves behind a carpet of aerated water. The propellers lose their traction in the foam and then if you don't get back into good water, you might lose enough speed to get hit by the wave behind you.
I checked over my shoulder as the bow lined up to follow the wave in front of me. There was a fifteen foot swell standing up about twenty feet off my stern. Holding to the "head on a swivel" mentality we were always applying, I returned my focus to the bow. The wave in front of me was getting away. I looked astern again, the wave was catching up, about fifteen feet behind us now and getting steeped as it prepared to break. There was nothing I could do but hope we accelerated. My right hand vainly pushed harder on the throttles, which were already full ahead. If I turned to get out of the path of the breaker, I would lose speed and most likely get hit broadside. Everyone was staring at the breaker, ten feet off now.
We finally met the speed of the breaker and moved farther ahead of it. We continued down-swell and exited the surf zone.
We graduated after the third week and returned to our units. After patiently waiting for the right weather in Gloucester, I got underway with one of our BM1s and became a certified Heavy Weather Coxswain.
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