Only they can tell us the exact series of events that led to the swamping, but after 15 years of boating with Yamaha jetboats, I can tell you that when the front of the boat is pointed into the oncoming waves, you HAVE to keep the power applied and understand how the boat behaves in waves. If you cut the power, the nose comes down and you start taking waves over the bow. Also depending how close the wave peaks are, if you go too fast, you will fly over the top of one wave and nose dive right into the other wave. I suspect either of these could have been the case. Too much, or too little power.
This knowledge comes only with years of boating in the ocean and I myself took a wave over the bow of my Exciter when I first owned it that scared the bejesus out of everyone on board. It happened right where the Miami river meets Biscayne bay. There were a couple of big boats going by causing a bunch of waves and wake. I cut the throttles to let a boat pass and stuffed the nose into the wake. I ended up with about a foot of water in the boat almost instantly (which is no big deal for an exciter, but my passengers didn't know that and started to panic).
In my opinion, that is the Achilles heel of our boats. The sloped bow is great for boarding and flat water, but if you loose power due to clogged intakes or some other issue at the wrong time, it could spell disaster. I never beach nose in, so the low bow has no benefit for me. I wish it had a traditional "Deep Vee" bow. "Love the back, Hate the front"
Your comments about everything are spot on. Our story started with taking a few good waves as we were heading out. Nothing deeply concerning at first, but large enough that the kids where overwhelmed. We then hit some seaweed that clogged the port engine. The boat started to come off plane just as a big wave come over the bow. Once that happened, the boat filled (slightly above our ankles at first). Both engines were still running, but, with a heavy cooler in the front, the entire boat pitched forward and the bow porpoised. I put the engines in reverse to try and get the bow out of the water. I then walked up front to release the heavy cooler, but the nylon straps had tangled under the cooler and I couldn't release them. As I was going for a knife to cut it free, both engines died. There were a few other boats nearby and they helped call the coast guard. We started to bailing, and both bilge pumps were pouring out water.
The Coast Guard arrived very quickly, and after several tries, they were able to get close enough to get everyone off the boat. We called BoatUS (since I'd signed up for a towing policy), and they arrived shortly there after. They said we'd have to wait until boat was pumped out before towing. At the time, I didn't fully understand why, but now I do. If you've ever been hit by a really large wave, you'll understand how much force/damage it can do. Towing a boat full of water slams everything around, as I later found out.
Things I'd do different:
1. I'd packed the cooler up front to try and smooth out the ride; as other people have echoed this is fine for a small chop; this was not a small chop. I should have quickly moved it to the back of the boat when the waves kicked up.
2. We had several extra tanks of gas, based on hearing that there was a run on gas after arrival last year. Unfortunately, I'd lashed the gas cans down to the swim deck (it seemed like the safest place for fuel) in a way that I couldn't easily open up the hatch to access the cleanout ports. Especially in the midst of chaos.
3. After the water got in the boat, everything that wasn't tied down got in the way. I'd make sure that everything is stored completely out of the way before taking off.
4. If you put all of the expensive electronics in a drybag, make sure it secured in place where it can't snag on any stray bolts or sharp edges. It was floating in the boat when we evacuated in to the Coast Guard boat. When I started to clean out the boat, I picked it up and water drained out the hole that had been torn in it. Between camera, iPads, laptops, cell phones, kindles, let's just say that was bitter pill. Or a really, really, really expensive pill.
5. Don't take the fancy camera out of Pelican case just because a F1.2 lens will be able to get a good shot at 6 AM lighting level. Stick with the waterproof GoPro.
6. Arrive a little earlier so that you have extra time to review where everything is packed on the boat and how it's anchored down.
Things that I'd do again:
1. Buy BoatUS towing insurance. I think it was a little over $100, but totally worth it. I never thought we'd use it, but very worth the money. Everything was completely covered.
2. Keep *all* camera gear in a Pelican case. Everything *in* the case survived. Even after floating outside the boat and getting beaten by the waves. It saved several Canon L-series lens.
3. Have a backup, floating, waterproof VHF radio with floatie. I was running around the boat, and it was really helpful to have it. I'd likely upgrade to something that has DSC for the next trip, as it was hard to get coordinates as we were taking on water.
4. Install extra high-capacity bilge pump hard-wired to extra large (AGM sealed) battery. Even with all electronics totally submerged, the pump was able to completely empty the boat in about 45 minutes. We watched the whole time as it just kept pumping away and the boat popped back out of the water.
5. Keep all important documents in a small pelican or waterproof case on the dashboard. This included car keys, boat registration, passports, wallet, and insurance papers. I keep it velcroed to the dash and I was able to grab it as we got off boat. Having everything was really helpful for dealing with the aftermath.
Notes about clean-up:
1. Get the plugs out of the engines as soon as you can. Run the engines to kick as much of the water out as you can. Note that this isn't a little water spitting out. It was enough to drench the three cars parked next to boat. And yes, it's coming out under high pressure.
2. Getting a long air nozzle that fits down though the spark plug holes really helps get the water out.
3. Plan to make friends with OPEC for oil. I've now changed 12 gallons of oil and it's just at a point where it looks like normal oil. Change the filters every two or three oil changes. I've gone through 8 filters so far.
4. Don't underestimate the damage of the salt-water. All the amplifiers, radio, and several harnesses under the dash are were trashed. The main battery is dead (it was a vented design). The AGM battery seems to be fine.
5. Spray everything with Salt-Away as soon as possible. Common sense, but really makes a big difference.
Happy News!
We took the boat out on the lake yesterday, and most things are returning to normal. I've still got to replace the radio, amps, and some wiring, but this will all come in time. Next year, it will likely be a guys trip on the boat with wife and kids taking the ferry or flying.