Single Screw Handling in Following Seas

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I'm with the crowd saying that throttle management is 80% of the game with following seas. Then a modern auto pilot can do its thing much more effectively. However, if you are dealing with highly confused seas rather than a regular period set from one direction, it's pretty hard for either human or machine to steer perfectly when there is no way to "anticipate" anything with high accuracy.
 
I'm with the crowd saying that throttle management is 80% of the game with following seas. Then a modern auto pilot can do its thing much more effectively. However, if you are dealing with highly confused seas rather than a regular period set from one direction, it's pretty hard for either human or machine to steer perfectly when there is no way to "anticipate" anything with high accuracy.


Yes, that's why the ocean racing boats have a steersman and a throttle man.
It's just too much for one man to do alone!
BTW they don't appear to be using any autopilot.
 
Yes, that's why the ocean racing boats have a steersman and a throttle man.
It's just too much for one man to do alone!
BTW they don't appear to be using any autopilot.

Kind of an apples and oranges analogy. A boat doing 100 kts ins't going to have its stern pushed around in an 8 kt following sea.
 
Interesting. Our past boats had P hulls, so we zipped across them at high speed. The AP had no issues on big swell days, even at lower speeds come to think of it. When entering a channel down here that is known for big swells in the Winter (Mission Bay), I was able to stay behind the wave in front by cranking up the speed to match it.

The single engine SD trawler will be new to us, but with that said, I have spent alot of time on vessels of varying size since I was young and I don't recall ever experiencing the severity noted by the OP. IE, a "32 ft. vessel doing a 180 on 2 - 2.5 ft. swells". I am not saying it didn't happen, and others are validating it, just surprised to hear this.
 
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I'm also surprised that a 32 foot boat is at risk in 2 foot waves. It would certainly limit the weather windows for boating.

I just checked the local weather. The forecast does not predict the waves to be 2 feet or less any time over the next week. 17 feet predicted on Monday. That will toss a boat around.

https://www.seabreeze.com.au/weather/wind-forecast/adelaide
 
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2 foot breaking ocean waves and 2 foot curlers in an inlet are 2 different animals.
 
2 foot breaking ocean waves and 2 foot curlers in an inlet are 2 different animals.

On the ebb no less.
Yep, speed and steepness are the whole game. Like the difference between running into a 2' brick wall or over a 6 foot wide 2' berm.
 
It seems to help having minimal flat surfaces other than a large rudder.
 

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[QUOTE

[/COLOR]It's VERY unusual to find waves like we encountered in that video I was shooting when we took green water over the fly bridge. That day was kind of the "perfect storm" of bad conditions. There was a several knot current running opposed to about a 30kt wind. The waves were short duration and steep.


They're not really going upstream, but give the illusion of that because of the wind. Take a look at this video below, look at the whitecaps. They're breaking upriver, against the current. That's what gives the illusion of them going upstream. It's an odd combination of a fairly strong current and high winds that gives them that appearance.
Makes for some interesting boating at times.[/QUOTE]

In total the view of that water resembles our normal 2-3 foot water. Short waves with white caps. Bucking them is not the most comfortable ride in our 28 foot boat, but as stable as it is now, it is really more a hobby horse issue, not a wild frolicing side to side ride. Those same waves on the stern do cause us to whip yet we can anticipate to the degree that while tiring, not that uncomfortable. Never a sensation of broaching. just a unaware juke if caught off guard.
Thanks for the video
Al-Ketchikan
 
If you are using an autopilot increase the response rate if the A.P. allows that. If it is set for a slow response then it cannot react fast enough.
When mine worked I used to crank up the response rate.
Granted it can only react but the rate of reaction should be adjustable. Use it if not done yet.
 

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