"This is what happens to an IPS propelled boat when it hits a rock!"

That's bad, and highlights a vulnerability that everyone suspected and feared, but were assured wasn't the case. Undoubtedly there is a stress point where the drives are designed to sheer off at. Below that they should stay in place and take the damage like any other drive system. There should not be an in-between point. Those pics will put a crimp in IPS & Zeus sales.

This does not look like a high speed hit of a rock. More like a softer hit of the sea floor.

Hi,

I would tend to agree with Lars on this one.

2nd that motion. Or should I say... +1

I disagree with this. These drives have been run aground hard, at the very least... at an on-plane speed. The damage to a conventional shaft/strut/prop/rudder system would have been equally severe, and just as costly.

One of the programs I headed up some years ago required a craft to be beached at a high rate of speed, with no operational damage. Because we were using pumps, this wasn't a problem. Sand intrusion into deployable systems was the real culprit. I became intimately familiar with the ensuing damage on conventional systems.

I was at a Ft. Lauderdale yard a few weeks ago and saw an Azimut 85 in for repairs. Apparently the boat was run into a reef by the captain at planing speeds. Lots of hull damage, running gear managled, anchor was even launched off (its an 85 kg anchor). The owner who was onboard suffered head injuries. Incredibly, the boat did not take on any water! (Who said Azimut didn't make a solid boat?! )

Repair Bill: $150K

Fine for hitting and repairing reef: $250K

Search for Mexican captain who took flight after being rescued: Priceless!

I agree also +2. However, I don't think this system really shouldn't have allowed the engine room to flood due to that kind of impact. It should have been built strong enough to survive that without massive water intrusion. The bottom skegs didn't even break off of the drives and it looks like it hit a softer/medium bottom from the pictures and not rock. I don't think the damage would be any less severe with conventional drives, but I highly doubt that conventional drives would allow enough water to come in to completely flood the engine room with this type of impact.

+3....

Since we don´t have the whole story (yet), we can only guess. My guess is that if the boat stopped when it hit the sea floor, it may have been leaning on the drives, waggling and breaking up enough to start leaking, without sinking as it was shallow. Then pumped and towed to shore.

Or this is the situation where it is impossible to judge at what impact the drives should come off, two knots more might have been the difference, or if the angle of the sea floor should have been steeper as it now seems to lift more than push the drives at impact.

Still shouldn't happen. This is exactly what people feared with pods, i.e. that they would open the hole on impact. To me this means back to the drawing boards for IPS & Zeus.
Did both drives allow water intrusion?

Perhaps they must build in forward facing sonars in the drives...

Hi,

This was extracted from the original article on the Thailand Boating Website.

Really there is only one preferred system in Asian waters and that is the tried and true shaft and strut. Why? Like everything else which works it is simple and easy and repairs can be done at any local Thai shipyard.. Asian waters carry a huge litter burden which often results in prop strikes and reverse facing props are slightly protected by the shaft carrying strut, the angle away from the hull of the boat and the sturdiness of the prop blade itself. The same cannot be said for the latest IPS system from Volvo which faces the props directly into the water stream which means that the first encounter a piece of flotsam has with your boat, is with an extremely delicate pair of counter rotating props spinning at high speed, just below the hull pressure wave. The first two boats delivered to Phuket with this system attached, suffered the same problem of propellor strike resulting in the replacement of a pair of counter rotating props on both boats on their delivery voyages.


They might have driven over something below the surface and the impact slight and just bent the props a bit and moved the drives without knocking then off.

The fact that they say it happened to the first two boats makes me think it is more of a co incidence that one would normally see in such a small control group. I wonder if we will ever find out what actually happened.

Except for the headline: "This is what happens to an IPS propelled boat when it hits a rock!"

Hi,

Oops, I must have been having a senior moment .

I'll take shafts & struts over IPS any day after seeing this. Although I've seen struts ripped from the hull after grounding. Either system, stay away from shallow water.

I don't see the props being mangled as that big of a concern. That would have been the result no matter what drive system they had. The fact that the pod didn't either stay put or break off and seal itself is a major concern.

It would appear she was making a hard turn to port when grounded. The IPS signature turning heel would put that drive into the bottom first, thus bending the skeg to port as in the second image and likely throwing her over to the opposite heel while still in a port turn. The steering may have survived the hit to be in any position when they were shut down.

Perhaps more testing is needed for lateral impact. Or maybe, and even more likely, an improved torque testing procedure for Sunseeeker's drive assembly sandwich is in order. The system is designed to snap off if the union top-to-bottom is sound and to spec. Thus blanket statements of "back to the drawing board" are born of a Press mentality, and maybe of a personal fixation and drive preference.

Like it or not, this drive system is real, has significant advantages, and is changing the way people part water.

Ps:

Oh, and if anyone could look at those pictures and say she hit rock, that person should be automatically disqualified from rendering any valid opinion.

Actually, if you check my posts on the pod threads you'll see that I have been a proponent of pod systems for a very long time. In fact I've promoted and sold them on Chris Craft (one of the 1st boats to use them). However this is intolerable. If it breaks away from the hull it has to seal. Period. Until then it is back to the drawing boards.