Questions on Swamping and Submerging

[Jonah]

Hi all,

This isn't necessarily a Grady-related question, but you all have so much boating experience between you. I haven't found much information about the dangers of swamping your boat, or how to avoid swamping from behind, or even about momentarily submerging your outboard in a big wave. So, here are some questions:

• In the attached pic, you can see that my outboard doesn't require this 'folding wall'. Would it be wise to seal it up? Wouldn't that be more like having a higher transom, if I were ever hit by a wave from behind?
  
  What about situations like in the link below?* Is this guy's motor ok, or does it take a moment of submersion to affect an outboard?

Thanks!

* Link: https://www.youtube.com/watch?v=hxE7VRtGKMQ

 

[Sharkbait282]

Ultimately, run what'cha brung, and run your boat the way your boat wants to be treated.

I'm sure there are other open transom Grady White members that'll ring in, but unless you're willing to pay good money to have the folding transom fully sealed up and professionally matched to the factory gelcoat finish, you're likely better off leaving it as-built.

In terms of running your boat, I think it comes down to a general "careful in a heavier sea state," to avoid having the boat drifting or backing stern-to the wave state. When running with the sea state, taking care to avoid surging with the waves (not too fast, not too slow) will help you avoid ending up with a lot of water pushing over the transom. Older Mako's had some substantially open transoms as well, so I'd think the Mako forums could also provide some feedback.

I'd also recommend a thorough test of your bilge pumps and float switches. Like with a running hose.

 

[Another Distraction]

I swamped a boat and it sank and flipped over so quick nothing could be done. I was belly down on bottom paint thinking.....this isn't good.

I'll never buy an open stern boat again.

 

[fellinger]

I think you have the biggest risk of swamping a boat in an inlet on a strong outgoing tide and direct strong winds/seas coming into the inlet and you are coming in with the seas. Nothing worse than that in my opinion. This just happened to me on Sunday. Strong outgoing tide coupled with 20 knot SE winds and SE seas made for about 6' - 8' for me coming back into the inlet. The boat will have a tendency to 'surf' down the breaking wave face causing you to loose all steering and swamping or you go to slow and risk the wave breaking over the stern. It is not a fun situation.

 

[Jonah]

Thanks for the replies so far. I will definitely test the bilge with a hose.

On thing I don't understand about avoiding swamping from behind: if a wave comes over the back, and I just 'gun it', won't the boat pull itself out, just like when getting onto plane? Or would the wave stop the outboard from working? I suppose this goes back to my question about whether the guy in the video damaged his outboard.

Thanks!

 

[seasick]

That folding panel has to be folded down for me to fully tilt up my motor. In your case, it may not mater.
Note that your hull won't sink it is foamed. It may float with the gunnels near the water line but it wont sink. The deck and transom well are self bailing. If everything is up to snuff, water that washed over the transom will drain out and not enter the bilge.
The only places where water drains into the bilge are the forward lockers, the anchor locker and to a point the read lockers, battery and oil tank, if enough water washes over them.
You can swamp the stern by sailing backwards under heavy power. You can get swamped by other's wakes. You can and I have experienced washover from my own wake. It is pretty easy to do
As to the question of the motor getting wet, I have seen outboard motors submerged for short periods, raised, hosed off and started. For the most part, they can get wet. The wiring in the hull itself is not as forgiving.
So other than your feet perhaps getting wet during unusual times, I wouldn't worry if sealing that flap will make much of a difference.

 

[VeroWing]

I have first hand experience of completely filling the cockpit multiple times of a 22' Grady Seafarer around 50+ miles off the coast of NY/NJ in a violent storm with huge stacked waves breaking over bow for hours and I can tell you this: if we had not been in that notched transom Grady, I would not be here to share this information with you. If you keep the boat moving forward and have good bilge pumps, even with a cockpit so full that water it is exiting over the notch and going through cabin door slots, the boat will not sink, or at least it didn't in our case. If we were in the same storm with a full transom, we would have sunk and drowned. That is fact.

 

[Doc Stressor]

Leave the transom the way it is.

Notched transom boats seem to have a bad reputation because of the perceived problem of taking waves over the stern. Once you learn how to run your boat correctly, it just won't happen.

Notched transoms, especially ones like yours with a folding splash guard, offer a big advantage over a closed transom boat if you take water over the bow. Instead of waiting for the scuppers to drain the cockpit, as VeroWing said you can just put the boat up at sub-plane speed and let the water run out over the transom. I drop the folding door to do that in my 226. But I wouldn't recommend doing that until you have had more experience.

As far as avoiding swamping from behind goes, It's just a matter of learning how to use your throttle correctly. In general, you don't want to try to run in the big stuff up on plane. The guy running Jupiter Inlet in the video is an idiot and was going way too fast for the conditions. You never want to "grab air". When that happens, the boat is no longer under your control and making it or not becomes random. The correct way is to run off plane with enough speed to maintain control. Increase the throttle as you go up a big wave and chop it just before you reach the crest. Then begin to accelerate again just before you reach the bottom of the wave and continue accelerating up the next wave and cut the throttle before you reach the top. When you time this right you will not burry the bow. Repeat as necessary. You'll be able to tell how much throttle you need to just keep in front of each wave that you cross. Don't let one catch up to you.

You don't want to be increasing power as you go through the crest of a wave or your prop will break free, spin out, and can allow a broach. That's when the boat turns sideways to the wave and falls off. You can capsize after a broach depending on the wave height and period.

I learned this stuff the hard way fishing The Race and Plumb Gut off of Orient Point Long Island back when I was young and stupid. We would try to avoid drifting into the 10-15 ft standing waves, but sometimes with a fish on it couldn't be helped. After running that stuff for a couple of years, even at night, the inlets further south were not a big challenge. But I recommend discretion, even after you learn how to run an inlet correctly. Try to avoid inlets when the tide is ebbing strongly.

 

[Another Distraction]

Run over a lobster pot that fouls your prop holding you stern to on a windy day and you're swamped.

 

[VeroWing]

Ran my 22 Grady Seafarer for over a dozen years in the long Island Sound out of Mamaroneck and hit lobster pots at least several times each season and never ever came close to swamping. Many times had to cut the road off of the prop too, which is much easier on a notched transom. Not saying it cannot happen, but is extremely unlikely, and nearly impossible to keep enough water in the cockpit of a notched Grady to make it swamp. Possibly swiftly backing down in heavy seas, non working bilge pumps, pulling stuck anchor from the stern, or some other type of operator error could do it, but that could roll roll or swamp most any vessel.

 

[Jonah]

Thanks everyone; this is exactly what I needed! I now understand the benefits of the notched transom, the resilience of an outboard being quickly 'dunked', and the basics of how to avoid taking water over the stern in a following sea.

Very grateful for this online community.

And while we're on the topic, anyone have advice on using trim tabs in big waves? I think the strategy is to keep one's bow high when 'sneaking' over waves in a following sea, and to keep one's bow low when going over waves in a head sea. (For instance, I don't think the guy in the video would have launched so high if his bow had been trimmed down a bit, right?) At least, in my limited experience that seems to feel best so far.

 

[Doc Stressor]

No tabs with a following sea. You can use your tabs to bring your bow down with a moderate head sea. But in big seas or a bad inlet where you can't run on plane, don't use your tabs or you might burry your bow. A little tab on one side can be used to raise the windward side of your bow to reduce spray, but be very careful not to overdo it.