Hammar H20 Hydrostatic release

[jamiemoir]

Wonder if anyone has any experience of these units. Ours is now two years old and I know we should replace it but it looks fine (not sure how I would know if it isn't!) so I'm reluctant to spend the £70 needed to replace it if I don't have to. Does anyone know what it is that has a 2 year shelf life? I know I shouldn't compromise on safety so if the answer is "Don't be a meanie and get another one" then that's what I'll do. It's just with having the liferaft seviced as well at £400 the bills keep mounting up!
Thanks in anticipation of your help.

 

[pvb]

I don't have an HRU on my raft, and I'm not sure of the advantages, especially on a sailboat. I'd have thought that the circumstances in which a yacht sinks so rapidly that the crew are unable to chuck a raft over the side are pretty rare. There's also the possibility that the HRU might not work, as the recent Fenner recall demonstrates. It's an intriguing quandary.

 

[prv]

I don't have an HRU on my raft, and I'm not sure of the advantages, especially on a sailboat. I'd have thought that the circumstances in which a yacht sinks so rapidly that the crew are unable to chuck a raft over the side are pretty rare. There's also the possibility that the HRU might not work, as the recent Fenner recall demonstrates. It's an intriguing quandary.

If it doesn't work then you're no worse off than without it - you can always release manually.

The main reason I see for an automatic release is in case of being run down by a ship in fog. One minute you're sailing along, next the hull is stove in or split in half. I imagine anyone on deck is likely to be thrown into the water. After the noise and chaos has died away, a raft swiftly inflating itself on the surface is going to be a welcome sight.

That said, if and when I do get a raft on KS it's going to be below. There's simply not a square inch of space available on deck.

Pete

 

[pvb]

If it doesn't work then you're no worse off than without it - you can always release manually.

Are you serious? The boat would be at least 4 metres underwater before you knew it didn't work!

 

[prv]

Are you serious? The boat would be at least 4 metres underwater before you knew it didn't work!

So with the boat 4m underwater I'd be better off if I had removed the HRU just in case it didn't work, would I?

If it's a deliberate abandonment (even at very short notice) you're not going to be using a hydrostatic unit, whether one is fitted or not. You will want to launch the raft manually under control and try to get into it from the boat rather than the water. Nobody who needs a liferaft, and can reach it, should sit where they are thinking "it's OK, it will launch itself automatically soon". Given the length of painter, the boat is going to have to have gone down quite some way (or the raft blow some way downwind, which is probably worse) before it inflates. By that time the person who waited will have been in the water some time, and will be some distance away from the raft. It's not going to appear within arm's reach the moment their bum starts getting wet.

The time when hydrostatics are useful, as I said, is when you didn't expect to be abandoning ship. At that point, a unit which might release is still better than a lashing that definitely won't.

Pete

 

[pvb]

I just wonder what you thought you meant when you wrote "If it doesn't work then you're no worse off than without it - you can always release manually." It didn't make a lot of sense. However, I agree that an HRU which might work is better than a fixed lashing in the unusual circumstance of an immediate sinking.

 

[Norman_E]

If you do buy a replacement, be aware that fake Hammar H20 releases have been sold, and will not work.
http://www.usmsa.org/homepageuploads/safetyalert3.pdf

 

[prv]

I just wonder what you thought you meant when you wrote "If it doesn't work then you're no worse off than without it - you can always release manually." It didn't make a lot of sense.

I meant exactly what I said, and I think it makes perfect sense. I don't really understand how it could be seen otherwise.

I tried to write a comprehensive explanation, but it ended up very long and pedantic and I'm not sure it was useful. If you could say how you don't think it makes sense I could try to address those particular points instead.

Cheers,

Pete

 

[pvb]

OK, one last go, then I give up trying to explain.

The idea of an HRU is that it releases the liferaft when the boat has sunk.

It usually needs to be about 4 metres underwater before it will release.

Your comment was "If it doesn't work then you're no worse off than without it - you can always release manually."

But, by the time you discover it doesn't work, it's going to be some way underwater.

I merely thought you'd have difficulty releasing it manually in that situation.

 

[prv]

I merely thought you'd have difficulty releasing it manually in that situation.

Right. And is that "worse" or "no worse" than if it wasn't fitted?

Pete

 

[prv]

Hmm - a lightbulb begins to glimmer. Are you concentrating on the second half of the sentence while I'm concentrating on the first? I'd have to agree that "you can always release manually" isn't strictly correct, taken in isolation. To me it's a figure of speech meaning "you can release manually just as much as you could before", but I can see how it could cause confusion.

In any case, it's hardly an important point to debate

Cheers,

Pete

 

[pvb]

Hmm - a lightbulb begins to glimmer.

At last!

 

[Ruffles]

Does anyone know what it is that has a 2 year shelf life?

Last year I replaced one with an expiry date of 1999 that came with the boat.

I was surprised to find that you set the expiry date yourself when you install it. Which suggests it's not a question of shelf life but life in service.

I imagine they are designed for commercial craft where they will be permanently fitted exposed to the elements. I keep mine down below with the life raft when the boat isn't in use so it gets a months use a year if that. So I'll be in no hurry to replace it.

I still have the old one somewhere. I must attach it to the anchor sometime to see if it would have worked.

 

[pvb]

I was surprised to find that you set the expiry date yourself when you install it.

According to Hammar, the expiry date has to be marked by an "authorised liferaft service station" otherwise it's not valid, whatever that means.

Incidentally, I've noticed that lots of yachts use the regular yellow Hammar release (designed for rafts up to 150 persons), but that for small rafts (4 to 12 persons) Hammar have a special green "Small Rafts" version which has a lower breaking strain for the painter line connection. Wonder which one is most often fitted to leisure yachts?

 

[BlueSkyNick]

I was surprised to find that you set the expiry date yourself when you install it. Which suggests it's not a question of shelf life but life in service.

When i started this very same topic a year or two ago, it was explained to me that it is nothing to do with how long it has been 'in service' , but how long since the unit was made, ie the shelf life.

whether it is installed on deck or not doesnt affect its reliability.

 

[pvb]

When i started this very same topic a year or two ago, it was explained to me that it is nothing to do with how long it has been 'in service' , but how long since the unit was made, ie the shelf life.

No, it can't be anything to do with how long since it's been made, as units can be in stock at retailers for months or years.

Surely it's just another example of phoney "death dates", like we see on flares, drugs, food, etc?

 

[BlueSkyNick]

No, it can't be anything to do with how long since it's been made, as units can be in stock at retailers for months or years.
?

Which is exactly why they put an 'end date' on them. The manufacturer cant have any idea how long the retailer is going to hold it in stock.

Its condition doesnt change any differently between being on a shop's shelf, in a boat's locker, or installed on deck so the 'end date' remains the same for all units made at the same time.

 

[pvb]

Which is exactly why they put an 'end date' on them. The manufacturer cant have any idea how long the retailer is going to hold it in stock.

Its condition doesnt change any differently between being on a shop's shelf, in a boat's locker, or installed on deck so the 'end date' remains the same for all units made at the same time.

Sorry, you've completely misunderstood. The expiry date is only marked when the unit is sold - read the Hammar literature if you don't believe me. It's then "valid" for 2 years.