A yacht hit a whale off Norfolk Island and went down. What we'd do on a catamaran

On Saturday a 51 ft Australian yacht called Tai Tam hit a whale about 250 nautical miles north of Norfolk Island, started taking on water, and the four aboard ended up in a life raft until a cargo ship got to them on Sunday morning. Everyone is alive. That is the water we sail every year between New Zealand and Fiji, and to be honest it is the one thing on a passage we have never had a proper plan for. So this is us sorting that out, in public, with the gaps left in.

What happened to Tai Tam

What Maritime NZ has put out:

• EPIRB alert to RCCNZ at about 1pm Saturday 26 September, NZ time, from the 15.5 m Australian-flagged yacht Tai Tam, about 250 nautical miles north of Norfolk Island. Struck a whale, taking on water, began sinking. Seas up to 2 m.
• Four crew abandoned to the life raft. An RNZAF P-8A went looking and ships were diverted.
• MV Sofrana Surville, a 143 m cargo ship, had them aboard at about 6am Sunday, bound for the nearest port.

RCCNZ operations manager Mike Clulow said the crew did all the right things and that setting the EPIRB off early was the key to getting them out. Alert to pickup is about 17 hours. The release is on News Wire and 1News.

What we don't know: the type of yacht, where they were going, what they hit, where the hull opened up, or how fast the water came in.

How often this actually happens

Less often than the headlines make it feel, more often than most crews plan for. A 2012 survey counted 111 collisions and 57 near misses, and the Marine Mammal Advisory Group database is now close to 1,000 incidents. Most did no damage. A handful sank the boat. Yachting World has the detail.

Two cases worth knowing:

• Raindancer, a 1976 Kelly Peterson 44, March 2023. Hit from underneath 1,200 miles short of the Marquesas. The whale came up on the propeller, the load burst the shaft log and the skeg cracked. Gone in about 15 minutes. EPIRB on before they left, and a catamaran found them nine hours later off a flare and a personal AIS beacon.
• One Tree Island, an Atlantic 46 catamaran, August 2020. Hit a sperm whale 1,500 miles from the Marquesas. Two cracks in the port hull above the keel, water pouring in through a hanging locker. T-shirts and bungs in the cracks, forward compartment shut off, pumps going. The port hull flooded to chest height and stopped there. A longliner had them off within six hours and they never launched the raft.

Those two are why we wrote this. Raindancer was hit aft, behind anything that could be sealed off, and went down in the time it takes to boil the kettle. One Tree Island flooded one hull and sat there. The difference was not cat versus mono so much as where the hole was and what was on the other side of it.

Where the water comes in

Nobody hits a whale with the bow, or hardly anyone. The boat is doing six or seven knots and the whale is asleep on the surface or coming up under you, so the strike lands where the boat is deepest and the gear sticks out. On a monohull that is the keel, rudder, skeg and shaft. A heavy old solid glass hull with a long keel can take a whale on the keel and carry on, and plenty of owners will tell you theirs bounced off one. The shaft log and the skeg are a different story, and they sit aft, well behind the collision bulkhead.

On a catamaran the hulls are shallow and there is no big fin to take the load, so it goes into the hull skin low down, a saildrive leg or a rudder. Mā Tori is a Fusion 40, 1.1 m draft, twin Yanmar saildrives, solid glass below the waterline (the build is in the Fusion 40 review). The bits we worry about, in order:

1. The saildrive legs. A lump of aluminium under the hull with a rubber diaphragm sealing it. Hit it hard enough and the leg goes or the seal does, and you have a hole the size of the leg cut-out. Nothing plugs that.
2. The rudders. Bend the stock and the bearing housing can crack.
3. The hull skin low down. Solid glass is tough but not thick. A crack there is the One Tree Island problem.

The bulkhead argument, and where we got pulled up

The first version of this post said sealed bulkheads buy a cat hours that a monohull does not get. Someone on one of the sailing groups pulled us up on that within the hour, and he was right to. Monohulls have had crash bulkheads for a very long time, most offshore monos have a watertight forepeak, and a heavy solid glass boat from the seventies or eighties is a lot harder to open up than a modern light one. We should have said so. This is the corrected version.

What a cat actually has going for it is not the bulkheads on their own, it is what is on the other side of them. Fill a compartment aft of the crash bulkhead on a monohull, which is where the whale usually hits, and you are pumping against the sea with a lump of lead under you. Fill one compartment on a cat and she sits down on that side and floats on the rest. Fill the whole hull and she sails like a pig, but the other hull and the bridgedeck are still holding her up. That is what kept One Tree Island afloat, and why we would not be in a hurry to get in the raft.

None of that makes a cat unsinkable, and the compartments are only real if someone made them real. On an owner-completed boat the bulkheads are as watertight as whoever ran the last hose through them. One unsealed pass-through turns a compartment into a delay. We have never had a hull full of water to test ours and we are not going to pretend otherwise. Looking at a cat, put a torch on every bulkhead penetration on survey day, it is on the list in the Catamaran Buyer's Pack for that reason. Looking at a mono, ask where the crash bulkhead is and what is behind it, because the whale is probably not going to hit the bit in front of it.

The first ten minutes on our boat

What we would do, in order. Not what we have done. Four round trips and we have not hit one, and to be honest that is luck.

1. Stop the boat. Heave to or dump the sheets. Speed drives water in and you cannot hear where it is coming from.
2. Find it. One person per hull, floorboards up, engine bays and saildrives first. Listen for it as much as look for it.
3. Shut it off. Close the door on that compartment if it has one. Bungs, rags, a cushion and a floorboard braced across it. One Tree Island's crew said the one thing they wanted was a bag of cricket ball sized epoxy putty balls. Carry them.
4. Pumps on, all of them. Electric, manual, and the engine raw water intake if you shut the seacock and pull the hose. Know before you leave which hoses that works on.
5. EPIRB on if it is gaining on you. Not once you have lost. RCCNZ can stand a search down. They cannot start one from a beacon you did not press.
6. Tell someone. We carry Starlink and Iridium. Position, boat name, number aboard and what is happening, to RCCNZ and whoever follows your tracker, then a position every fifteen minutes.
7. Raft ready, not launched. Lashings cut, painter tied on, grab bag beside it. Then back to the pumps. You step up into a raft, never down, and on a cat that is still floating you may have hours where Raindancer's crew had minutes.

Where the gear lives

Your boat, not ours. Stand in your cockpit and check these.

• The EPIRB has to be reachable with one hull flooded to the bunks. In the bottom of a locker in one hull, it might not be.
• The raft has to go over the side without anyone going forward on a deck sloping the wrong way. The transom step or the cockpit roof is where most cats put it.
• The grab bag needs the handheld VHF, PLBs, sat phone or Starlink Mini with a battery, water, a torch and the ship's papers, and one person has to be able to carry it.
• Both of you know where all of it is, not one of you.

In New Zealand the Cat 1 inspection goes through the raft, EPIRB and flares before you leave (see the NZ buying guide). Check the current Yachting New Zealand requirements before you rely on anything here, they change.

Cutting the odds

You will not see a whale asleep on the surface at night, or one coming up under you by day. What helps is where and when.

• Late September is spring. DOC says humpbacks head north past New Zealand in winter and come back south in spring, so right now they are heading home through the water the fleet uses to go north. We don't know what Tai Tam hit. We do know the timing.
• Slow down where you have just seen blows, and if you see whales alter course wide and early and put the engines in neutral so the props stop turning. Load goes up with speed, and on Raindancer the load through the prop shaft is what did it.

You don't prevent a whale strike on a passage. You survive it or you don't, and most of that is decided before you leave the dock: the bulkheads, the bungs, the putty, where the EPIRB is and whether you push it early. Tai Tam's crew pushed it early.

Questions people are asking this week

Can a catamaran sink after hitting a whale?

Yes. A cat has no ballast keel and a lot of volume in the other hull, so one holed hull often floods to the waterline and stops, as on One Tree Island. Open a hull up badly enough, lose a saildrive into a compartment that was never sealed, or flood the bridgedeck, and she can still go down. Monohulls have crash bulkheads too. The difference is where the whale hits and what is behind that bulkhead.

Should you set the EPIRB off straight away?

If the water is gaining on you, yes. The rescue centre can always stand a search down. Tai Tam's crew set theirs off early and RCCNZ said it was the key.

What should you carry to plug a hole?

Soft wooden bungs tied to every seacock, a bag of epoxy putty balls, rags, and a floorboard you can brace across a crack. None of it covers a saildrive cut-out, which is why that compartment has to hold on its own.

Keep reading: the water Tai Tam was in is covered in the Fiji to New Zealand passage guide, and our bluewater catamaran for sale is the boat all of this was written from.