Navigating in rough waters, doubts.

[Jmnemonic]

Hello, i'm new to motorboating, yesterday i went out with my six meters boat, equipped with an Honda BF90, the se was rough, I've no experience, but I thought it was not a good idea to accelarete and start planning, I pushed the honda til 3500 - 4000 revs, the boat seems like doesnt go forward sometimes, and sometimes I felt like I was over the wave, riding it, but it was the feeling, like the boat doesnt go down, while the motor was pusshing at 4000 revs, my question is . . . how to handle the boat in rough waters and if this performance for my boat is right.

Thanks in adavance.

 

[bob johnson]

Re: Navigating in rough waters, doubts.

just way too little information...

all we know is how long your boat is...is it a canoe( sarcasim!!)

90 hp on a 20 foot boat isnt a LOT of motor....but who knows ,

how heavy is your boat??? what kind of hull?

how stormy was it???swells ?? chop??? heavy winds??

has the motor ran good in good weather for you???

you should set your boat up for normal conditions. that is the way to determine if everything is working...when you get to storms....you just learn what the boat and motor and you combo can handle...

not that you would make any changes for such conditions in your motor or set up!!!!

there is definately a leanring curve for handling rough seas....and a few thresholds you need to be aware of!!!

bob

 

[Lrider]

Re: Navigating in rough waters, doubts.

just way too little information...

all we know is how long your boat is...is it a canoe( sarcasim!!)

90 hp on a 20 foot boat isnt a LOT of motor....but who knows ,

how heavy is your boat??? what kind of hull?

bob

LoL you just need to know everything huh

I had a very lite starcraft out in the pacific one day the swells were about 3-4 feet, not stormy so it wasn't too bad. What I did notice while trying to get back to the breakwater was the swells were moving faster then me and in the same direction. Was interesting that the boat did not have enough power to climb the swell so every time one came past the boat slid backwards, then increased speed down the face of the swell coming up on me. Seems like it took forever to get back in

 

[bcons]

Re: Navigating in rough waters, doubts.

More info is needed, but as said above depending on the type of hull 90 hp isn't much for an 18-20 in swells.

Do you have trim tabs? Did you have them down?
That can drastically alter the way the boat handles swells.
Then riding the wave? That can also make you feel like you're not moving as much as you think you should be. Eye's playing tricks on you, look at speed measured by a GPS which measures land speed or how you're really moving.
Your eye's can tell you one thing since they see the waves moving in the same direction there's no staionary point of refrence.

Then the physical effects, when travelling in the same direction as the swells (especially when they have a long frequency or big distance between waves)
At the bottom in the trough the water can be almost flat, boat seems to operate normally. When you're traveling not much faster than the wave, as you approach the back of the next one you're boat has too plow through the extra water, & basically Climb uphill also fighting gravity a bit.

Lots to get used too, you may not have any problem other than being new.

 

[bob johnson]

Re: Navigating in rough waters, doubts.

LoL you just need to know everything huh

I had a very lite starcraft out in the pacific one day the swells were about 3-4 feet, not stormy so it wasn't too bad. What I did notice while trying to get back to the breakwater was the swells were moving faster then me and in the same direction. Was interesting that the boat did not have enough power to climb the swell so every time one came past the boat slid backwards, then increased speed down the face of the swell coming up on me. Seems like it took forever to get back in

I had the same experience years ago in a brutal nor' easter off of CT..it was a 16 foot v hull utility boat with only an 18 hp on the back...

the waves were breaking at about 8 foot maybe more..the swells were not that big , maybe you two to three times the length of the boat..

the sides were steep!!! totally could not drive into the waves... did that once when i just cleared the reef that was holding back the real dangers...boat fell through air after I crested the first wave...

so i have to ride with the waves...even though it wasnt the way i really wanted to go.... and the waves would push me badly, almost through the wave in front of me , then it felt like i was being sucked backwards into the next coming wave.....

about as close to death as i can think......for 4 miles!!! the winds were about 50 mph then....

weird how you feel like you are going backwards with the motor under power!!

bob

 

[Philster]

Re: Navigating in rough waters, doubts.

>Boating courses.
>Boat with experienced boaters to learn.
>Recognize that some conditions require hundreds of hours of experience.
>Recognize other conditions require thousands of hours of experience


Good luck. Get a 'feel' for things over time. Some guys never get the feel. It's intangible, but I hope you do get it some day. Kind of like dancing. You can learn, but it's flat out better to be born a good dancer. Still, wouldn't want to go to the ball without any lessons...

 

[2rz-fte]

Re: Navigating in rough waters, doubts.

right off the bat, if the swells are too big for your boat to handle, best option is to hit the waves at a 45deg angle or some kind of angle. that way you are not climbing the face and smashing your bow into the next one. worst case scenario is your bow plunges into the next wave and down you go.

hit the swells at and angle and if you must, zigzag your way back home.

 

[Jmnemonic]

Re: Navigating in rough waters, doubts.

just way too little information...

all we know is how long your boat is...is it a canoe( sarcasim!!)

90 hp on a 20 foot boat isnt a LOT of motor....but who knows ,

how heavy is your boat??? what kind of hull?

how stormy was it???swells ?? chop??? heavy winds??

has the motor ran good in good weather for you???

you should set your boat up for normal conditions. that is the way to determine if everything is working...when you get to storms....you just learn what the boat and motor and you combo can handle...

not that you would make any changes for such conditions in your motor or set up!!!!

there is definately a leanring curve for handling rough seas....and a few thresholds you need to be aware of!!!

bob

Hi again, thanks all for your replys, I will give you more data:

My Boat:

1998, 6 meters / 19 foot, Rio 600 Day, V hull, you can seen it here:

http://www.rioiberica.com/index.php?page=rio_boat&series=old&model=600Day

Weight: 1000 kgs / 2204 lbs (included outboard motor)

Weather condition: Not stormy, just wind about 15 knots, waves about 3 - 4 feet.

Performance in good weather condition:

25~30 knots max spedd at 5000 ~ 5500 revs.



Thanks again.

 

[ovrrdrive]

Re: Navigating in rough waters, doubts.

Bottom line in my opinion, if you're not comfortable in your boat when it starts to get rough turn around. I've seen people worry in 2' waves, and I've seen people not worry in 7-8' waves. It all depends on how confident and knowledgable you are and how well your boat performs in rough water. Everyone has a different tolerance level. When you're out you're the captain of your vessel and responsible for everyone in it. They don't know it but they put their lives in your hands each and every time they go out with you. Don't be the guy that kills his friends and family because he went out when it was too rough because the passengers really wanted to go fishing. I have takens my boat in several times because I felt the weather was about to turn bad. People respect my decision.

 

[bcons]

Re: Navigating in rough waters, doubts.

There have been alot of decent posts above, but being new & having a small pleasure boat like that you really need some classes & perhaps find a Captain (some specialize in privately owned boats, or a fishing charter captain that may be in his slow season) Hire them to take you out on your own boat & teach you.

As stated above so many variables, then lots of it will only come with time on the water. Trying to read about it & merely learn from our opinions may get you into more trouble.

A perfect example, someone above wrote taking waves at an angle, sometime that can help. When it's a rolling swell (big waves with little to no white caps & big distance between waves) it can help even in much larger waves 6 footers. However when it's blown out & choppy, white caps & waves are breaking 3-4' it can lead to worse problems. Not only will the boat being going up & down, it can also pitch violently from one side to the other all at the same time as you crest the wave.

There's really no easy answers except time, time, & more time. Wrong conditions & actions & 3-4 ftrs could swamp or capsize you boat, right conditions & right actions and your boat would be fine in 5-6' (albeit not so comfortable)

 

[bob johnson]

Re: Navigating in rough waters, doubts.

Hi again, thanks all for your replys, I will give you more data:

My Boat:

1998, 6 meters / 19 foot, Rio 600 Day, V hull, you can seen it here:

http://www.rioiberica.com/index.php?page=rio_boat&series=old&model=600Day

Weight: 1000 kgs / 2204 lbs (included outboard motor)

Weather condition: Not stormy, just wind about 15 knots, waves about 3 - 4 feet.

Performance in good weather condition:

25~30 knots max spedd at 5000 ~ 5500 revs.



Thanks again.

a Honda BF90 an outboard isnt it???

the boat in the picture is an inboard....no way they would put a 90 hp in there!!!

I cant imagine there is such a thing as a 90 HP inboard, unless it is a sail boat motor...

that looks like a lot of boat for a 90 hp..

bob

 

[Jmnemonic]

Re: Navigating in rough waters, doubts.

Hi bob, there are two versions of this boat, inboard and outboard, if you click on the photo area, you can see a drawing scheme for the outboard version.

In addition I've changed my avatar to let you see the back of my boat.

Yes its an Honda BF90, i dont know if its enought engine for this boat, in a good weather a 25 knots can be reached easily.

What do you think about it?.

Thanks.

 

[archcycle]

Re: Navigating in rough waters, doubts.

The most important thing IMO is to give serious attention to actively managing the throttle. It's a pain in the *** but once you wind up in That situation there is no set throttle position that will ever work. Find yourself a nice sweet spot and angle that you move through most smoothly and actively manage the throttle to stay around it.

Just remember hand on the throttle at all times ready to compensate up and down. Eventually you get a feel for it and can spend more time on the down slope feeling some power and being more in control of your position rather than feeling uphill and lugging.

 

[Boatist]

Re: Navigating in rough waters, doubts.

Average conditions out here in the Northern Pacific Ocean is 5 to 6 foot swells every 7 to 10 seconds with 20 knots of wind all summer long.

My boat is 21 feet and we do not launch if the swells are 8 feet or over and 8 seconds or less. We have been out in 9 foot swells every 6 seconds but not much fun and we came in 2 hours early.

Common to be very foggy (less than 1/8 mile) in the morning and 8 to 10 knots of wind. On the nice day swells will be 5 feet and 10 seconds apart in the morning then build to 7 to 8 feet and 9 seconds apart with 20 knots of wind.

Heading out to sea into the swells need to slow way down. I usually put trim tabs at least half down so I can come up on plane at about 12 MPH. Try to watch two to three swells ahead as you can steer side to side and miss most of the steepest Swells. Key is to go slow and watch the sea.

Coming back in the afternoon I feel is the most dangerous. At this point with a following swell you want all trim off. Swells will be running 18 to 20 MPH. Only safe way in is to ride the back of the swell but close enough to the top that you can see over the swell. You must be able to see over the swell to make sure there is not a boat coming out or a crab pot ahead. Riding the top part of the back of the swell you must always have one hand on the throttle to make sure you do not go over.
If you go over the swell the boat would gain speed down the face and maybe drive the bow into the swell ahead and pitch pole which is deadly. If you go too slow you can not see anything but swell ahead and have no idea if a boat is coming out.
If the following swell over takes you it can break on your stern and fill the boat with water.

When riding the top of the swell you can move along the top of the swell side to side to make sure you hit the channel and not the break water and rocky cliffs.

To start out only go out on the nicest days. Take someone who know the area and has lots of experience. Watch the weather and know local patterns.
As a example here if the fog lifts and you see sunlight hiting the blue water to the North NorthWest it time to catch your last fish and get the gear stored. Along with the Sunshine and blue water comes winds in the 30 to 40 knots range. Winds that high means everyother swell will have wind blown breaker of 2 to 3 feet and swells that are steeper and closer together. Time to get in ahead of the weather.

http://www.ndbc.noaa.gov/station_page.php?station=46013

 

[Philster]

Re: Navigating in rough waters, doubts.

^^^Good example.

If you are riding swells/rollers back into a inlet, especially a natural inlet from/to the ocean, at some point you are going to ride a swell that becomes a breaker.

If you want a steep learning curve, have a seasoned captain show you how to ride swells in a following sea and return home via an inlet where the waves break into the shallows. On top of the rhythm you need, at some point you need to jump a swell/breaker in the direction it is breaking, and not beach yourself on a sandbar/shoal. After all, if the water was deep enough, the swell/roller wouldn't break.

You have one chance to nail it. If you don't, a breaker is coming to break on you, and/or you've stuffed the nose of your vessel into the sea and are in an extremely vulnerable position.

Unfortunately, the best learning comes under the worst conditions.

 

[GatorMike]

Re: Navigating in rough waters, doubts.

More info is needed, but as said above depending on the type of hull 90 hp isn't much for an 18-20 in swells.

Do you have trim tabs? Did you have them down?
That can drastically alter the way the boat handles swells.
Then riding the wave? That can also make you feel like you're not moving as much as you think you should be. Eye's playing tricks on you, look at speed measured by a GPS which measures land speed or how you're really moving.
Your eye's can tell you one thing since they see the waves moving in the same direction there's no staionary point of refrence.

Then the physical effects, when travelling in the same direction as the swells (especially when they have a long frequency or big distance between waves)
At the bottom in the trough the water can be almost flat, boat seems to operate normally. When you're traveling not much faster than the wave, as you approach the back of the next one you're boat has too plow through the extra water, & basically Climb uphill also fighting gravity a bit.

Lots to get used too, you may not have any problem other than being new.

LOL I learned about small boat performance in swells a few years back. I followed a friend in a bigger boat across the gulfstream to Bimini in my 19 ft Wellcraft. The seas were flat when we crossed and I burned 25 gallons going over. We had a tripical storm come through while in Bimini and a week later when seas calmed enough to cross back there were 10 ft swells. I burned 55 gallons on the return trip and ran out of fuel 3 miles from Ft Lauderdale. I was shocked that we burned more that 2x as much fuel crossing it 10 ft swells as we did in flat seas.

 

[Lou C]

Re: Navigating in rough waters, doubts.

I took a look at that boat on their website...for a small boat it actaully looks well suited for bigger water bacause it has a high freeboard/full windshield all the way around...closed bow and it looks like the outboard is bracket mounted so there is no low cut out in the stern...
I would question if a Honda 90 is enough power for that boat...similar size boats here usually come with at least a 115 and more often a 150...
I'd try getting someone who is expereinced to go out with you and help you learn to deal with the various wave condions you will find...
I have a 20' with a 205 hp sterndrive and I usually will not go out if the winds exceed 15 mph and the waves are more than 3 feet...it's not the average wave height so much but the period between waves...here when it gets windy the period is very short which makes it much more difficult and then when you add tides and boat wakes to this it can get dangerous...I approach wakes/waves cautiously and try to slow down and keep the bow up as much as possible...

 

[Jmnemonic]

Re: Navigating in rough waters, doubts.

thanks to everybody.

About the issue if a 90 HP is enough for the boat, I think i will not have a very fast boat, but its enought to take off mantain a 18-20 knots cruise speed and look to be close to 30 knots when you play with the trim, I think for me, as a begginer is enough, and I will look for more speed and performance in the future.


About the problems with rough waters, i think there's just one way to solve the problem for me, practice, practice, practice, and look for tips and lessons from expertise people.

Thanks all.

 

[bcons]

Re: Navigating in rough waters, doubts.

One more thing, your prop can also make a difference. This would be something you'd need to talk to your marina about. Find out what exactly you have, & what are your performance options.
There can be a difference in boat performance based on the propellar.
Wether it's a 3 or 4 bladed one, & the blade pitch (angle at which the blades are to the center)
Some are optimized for power, others for top end speed.
If you're willing to sacrifice 1-2 knots of top end speed, you can often gain a faster more powerful "holeshot" or startup and much more power in the midrange RPM's & speed.

$300-$600 for a prop fairly easy to change & if you don't like it you can always switch back & it never hurts to have a spare one lying around.
Wether or not this is an option & what to try should come from your marina who should be knowledgable about what's possible.

Good Luck

 

[Jmnemonic]

Re: Navigating in rough waters, doubts.

Thanks for the advice bcons, the prop is a 3 bladed one, I dont know the blade pitch, but i will try to meseaure it.

Today the sea was almost perfect,almost no wind, almost no waves, I was testing and knowing better my boat, I think i can finally was enjoying from boating, it take off at about 20 knots, and mantain a cruise spedd of 17-18 knots at 4500 rpm.

I couldnt play with the trim cause is not working, the boat was very satable, and I cut the little waves with no problem

I think i can improve this performance.

What propeller do you recommend for this boat?

And do you think this can help?
http://www.francobordo.com/alas-estabilizadoras-mas-de-50cv-lalizas-p-837.html