Driving in rough water

[jumpjets]

I have a 23' I/O dual prop boat (see sig) that I like to take out on the Atlantic. I always stay within a mile of beach since it's single engine. How should I be driving it to minimize the rough ride in rough water? Trip full up, trim full down? Obviously, I slow way down, but am I damaging the boat by staying up on plane and smash through waves?

I dealt with about 3-4 foot swells today. It was manageable, but it was rough enough to be "work" instead of "fun".

 

[Scott Danforth]

there is no right answer, as it depends on size of boat, direction of wind, your travel, direction of waves, height of waves, speed you are attempting, etc. I generally have the trim up a degree, tabs depend on direction of the seas. Speed is the number one factor, the bigger the waves, generally the slower you need to go unless you get a bigger boat. too many times people just beat themselves senseless trying to go fast in rough water.

however a steady hand on the helm, feet firmly planted, head in the game, and hand on the throttle (as you need to adjust your speed with relation to the speed, direction, and height of the waves), and you can get through most less than desirable weather.

http://www.boatsafe.com/nauticalknowhow/waves.htm

3-4 foot swells is normal. the 7-8 foot waves are the ones that pucker the upholstery right off the seat. I know from experience that 20 miles of 7-9' waves in a 19 foot boat are not fun.

 

[tpenfield]

I agree with Scott, lots of variables. I would not put a Rinker through a pounding of 4 footers though. It is not an off-shore style boat, so you may have stress cracks develop on the hull.

Slower and a moderate trim would be best. You may find that in a 2-3 foot chop, you can maintain a higher speed and have the hull cut through the waves. As the waves get larger, the boat will tend to bounce too much and become airborne as higher speeds.

 

[Chris1956]

Generally, in rough conditions you want the bow down, to allow the pointed part of the bow to cut thru the waves. Power trim tabs help make this happen. If you do not have them, usually trimming all the way down is the best you can do. Trimming down costs some speed and therefore fuel. Try some other trim angles, and choose the best speed with acceptable pounding.

 

[milehighjc]

It is not the ocean to be sure, but this is a topic I have tried to sort out better myself. The lake I boat on gets quite rough in the middle of a weekend day as a consequence of being quite crowded (typically rangers are limiting launches before noon), a lot of wake/surf boats, being narrow, with steep walls. The result is a LOT of chop by 10 or 11AM. I usually just opt to head for a cove after morning water sports, but eventually I always have to venture out into the main lake.

Im not sure if this is "doing it right", but it seems to help soften the ride a bit. For reference, I am a long way from an expert, I only have a couple of seasons under me in my 18' Crownline..

• Installed SmartTabs. This provided a huge difference in ride quality. It also meant that I could remain on plane at a lower speed.
• Carefully manage speed. I dont slam into large swells
• if there is a pattern in the waves, I cross them by quartering them. I dont run parallel, and most definitely do not run perpendicular to the wave. I look for an angle that will let me cut the wave with the bow, but get the hull to span the waves so that the bow rise/drop is minimized.
• If I cant "span" the wave, then I ease off the throttle immediately, get through the swell, the gently add the power back on before I drop off plane.

I still occasionally get slammed for a wave or two, but those situations are getting less and less common. My backside, and my passengers (especially those in the bow) are very appreciative.

 

[dingbat]

I have an offshore hull so I don't have specifics to add to the discussion other than to say "slow" isn't always your friend in the rough. Wallowing off plane from trough to trough isn't necessarily the most comfortable ride.

Trimming all the way down is just asking for problems unless piloting a submarine.

 

[Grandad]

So much depends upon the frequency of the waves, meaning the distance between crests. As mentioned above, changing the angle of approach can stretch this distance to match the size of your boat and your speed. In the end, if you're feeling every slam in your butt, it can't be good for the boat. I tend to keep the trim up slightly in my 21' if I think there's any chance of punching her nose into waves. That will depend on your boat's design (open or closed bow), how much it weighs and how much load is in the boat today. So, ya, there's no simple answer. - Grandad

 

[rallyart]

It makes a very significant difference if you are following the waves or heading into the swells. When travelling in the same direction as the waves are you do not want the bow down. It increases the risk of burying the bow into the back side of the next wave as you ride down the front of the first. If you are heading into the waves yon can normally run better with the bow trimmed down as you don't want to be launching your bow off the crest.
It's really a skill you have to develop to travel in large swells or a storm. Waves can double up easily and yu get cross waves to throw your planning off. Generally I would prefer to stay on plane, if I can. Helm adjustable trim tabs help a lot and give you more options than just the engine trim.

 

[airdvr1227]

No standard answer except to say if you don't feel comfortable and in control slow down until you do.