The case of the grounding of
Deep Blue is not as simple as it first seems. A New Zealand
Maritime Safety Authority Accident Investigation Report investigated
by Jim Lott, NARB, concluded that “the anchor failed when
the bolt securing the two parts of the anchor fell out”
and “that this could reasonably be attributed to the failure
of the nut that secured it”. What the investigator seemingly
failed to consider is how this could have possibly occurred
when the type of nut used is specifically designed not to come
loose, and there were no forces acting on it.
Spade anchors are designed to dismantle into two
pieces for easy stowage, a very popular feature. The shank is
inserted into a socket on the blade and retained by a stainless
steel bolt with a “Nyloc” style nut. During normal
operation, there is no load on this bolt as the substantial
socket assembly takes all the force. At boat shows, we often
demonstrate this by removing the bolt completely and pulling
the anchor as per normal operation. Even when “break out”
is simulated the shank remains inserted in the socket clearly
showing that the bolt simply holds the two sections together.
“Nyloc” style nuts are used extensively
to prevent accidental loosening of nuts, normally associated
with high vibration situations. In the case of the Spade, there
is no turning force on the bolt/nut combination and little or
no vibration, “Nyloc” style nuts are used as a precautionary
measure to totally eliminate any chance of the nut coming loose.
“Nyloc” style nuts require tools and significant
force to tighten or loosen them. If the nut was initially tight,
and there were no forces acting on it to loosen it, it could
not have come undone. In my opinion, it is extremely unlikely
that the investigator’s conclusion is correct.
There are two other possibilities that the investigator
apparently fails to consider altogether.
1. The nut was never tightened
properly in the first place. This is a distinct possibility
as the anchor was relatively new, was purchased assembled and
was not subsequently disassembled. When the Spade anchor was
displayed, it is possible that the bolt was only loosely fitted,
as purchasers often wish to dismantle the anchor for transport.
(“Nyloc” style nuts are designed to be used only
once). It is possible that the owner/skipper failed to ensure
that the bolt was tight.
2. The nut, bolt and blade were
removed after the grounding. Apparently no attempt was made
to recover the anchor until three days after the grounding.
During this time somebody could have removed the blade. It should
also be noted that the vessel was not insured.
There are a number of other peculiar facts in
the case:
The owner was at the top of the mast fixing the
tricolor light at 2:30 am when the vessel grounded. The vessel
had been at sea for 7 days having encountered rough conditions.
They had anchored at 22:30 and then spent two and a half hours
providing radio communications for an emergency and helicopter
evacuation nearby. It is logical to assume that the crew would
be tired. The investigator apparently failed to consider that
this could have been a contributing factor.
Why was no anchor watch maintained even though
all three crew were on deck?
Even if the anchor blade had become separated
from the shank, the shank and the weight of the chain alone
would have been able to hold the vessel under the weather conditions
of the time. (NO wind or wind less than 10 knots)
The vessel was apparently anchored too close
to the shore and unprotected from the onshore wind.
The Model 80 Spade is designed for vessels displacing
up to 4.5T. Deep Blue was estimated to displace 6T.
The investigator concluded that the rope/chain
combination was sufficient as the ratio was 3.25/1. He failed
to take freeboard into account, which would reduce the ratio
to approximately 2.88:1. Whilst, according to the report, 3:1
is commonly considered adequate in calm conditions for an all
chain rode, this was below that and well below recommendations
of a ratio of 5/1 or better 7/1 for a mixed chain + rope rode,
especially if no anchor watch is to be
maintained.
In my opinion, any combination of factors could
have lead to Deep Blue dragging including the lack of adequate
scope, but the failure to maintain an anchor watch was the primary
cause of the grounding.
Despite doubts over the case, Spade have agreed
to modify future bolts, as recommended by the investigator,
to include a pin after the nut and a note advising that “Nyloc”
style nuts should only be used once. (There is no need to replace
the nut after each deployment, but every time the anchor is
dismantled). Existing owners are advised that if they have any
concerns about their nuts, that they arrange for the end of
the bolt to be drilled and have a pin and new “Nyloc”
style nut fitted. It is the owners’ responsibility to
ensure that the nut & bolt (or alternative) are in good
condition, secure and suitable for the purpose. It must be emphasised
that thousands of Spade Anchors have been sold since 9 years,
and that no similar cases have been reported.
Alain POIRAUD (designer of the Spade and Ocane anchors)
________________________
The following is part of the fax
we received from D Meeken
7/6/2004
Spade Anchor Company
Tunisia
Fax 00 216 71 865250
Attn. Alain Poiraud
D Meenken/Spade Anchor - Loss Claim
I request that the Spade anchor company accepts
my full claim for the loss of Deep Blue and pays compensation.
If compensation is not forthcoming, I will vigorously pursue
warning the international yachting community of the fact;
A spade anchor failed catastrophically,
directly causing the loss of my yacht Deep Blue (MSA report)..
Be aware that I have the capacity to communicate
these facts effectively, and globally;
I await your response.
Diederik Meenken
Master, Deep Blue
Fax +64 7 8558282
PO Box 21144, Flagstaff
Hamilton
New Zealand
__________________________________
webcraft (from PBO Forum on www.YBW.com)
I have a Spade anchor, and find this whole incident
bizarre.
The bolt does not take any of the anchoring forces
when the load is on the anchor - the shank is retained in the
fluke by the socket so the whole shank is the lever, with no
force on the bolt. Even if there was no nut on the bolt, it
is hard to see how it would come out under tension - in fact,
the anchor would still stay together under tension (ie when
in use) if there was no bolt there. The bolt is no more a structural
part of the anchor than the seizing wire used on the shackle
on your anchor chain.
The only possibility therefore - and very unlikely
in my opinion - is that the bolt came out while the anchor was
being deployed or was on the way to the seabed. If this was
the case then it should have been immediately obvious to the
skipper of Deep Blue that the anchor was not set properly -
unless he just threw the anchor overboard and took no other
positive action to ensure that the vessel was anchored. If so,
then the accident is no-one's fault but his own.
As for the assertion on Deep Blue's website that
no one would trust their rigging to a nyloc - well, for many
years I flew microlights. These are highly certified and subject
to stringent regulation, and many vital parts are secured using
nylocs. The main thing to remember with these nuts is that they
should not be used twice. It would be interesting to know if
Mr. Meenken had disassembled and reassembled this anchor at
any point and, if he had, whether or not he replaced the nyloc
with a new one.
I have the deepest sympathy for the crew of Deep
Blue, but I think there must be more to this than meets the
eye.
I do visually inspect my Spade regularly, but
do not feel that any other modification is necessary. I certainly
do not believe it is unsafe, and slept soundly in many windy
anchorages on our recent trip round Ireland. On two occasions
on that trip it reset immediately after a 180 degree wind shift
in 25+ knots - very reassuring.
My Spade anchor is not unsafe, and neither I suspect
is anyone else's - unless they are saving a few pennies by reusing
that nyloc after disassembling their anchor for stowage.
- Nick
__________________________________
tsenator ( PBO forum – www.ybw.com)
-HAVE YOU SEEN THE SPADE ?
I'm a Yank and have NO aliance to a French based
company BUT I have had a Spade 100 (Steel version) for over
2 years now and I am very happy with it. I have had a CQR and
a Danforth and they both seemed to work well, but the Spade
just seems a notch better It seems to set immediately and well
the first time and resets everytime there is a tide shift etc.
(knock on wood...don't want to jinx myself). It kind of fit
on my old roller but I modified it for the SPADE and it fits
very well now and it is now self launching AND self retrieving.
I put a remote anchor windlass switch in the cockpit and I can
drop and retrieve the anchor while short handling the boat.
Priceless !
Here are some pics of my set up https://www.imagestation.com/album/?id=4289197805
I have read about that story below and initially
I was alarmed, but then there are a few things that just don't
add up. Plus one must remember that they lost their boat (Keel
came up through the hull on a just 2 thumps on sand in the
surf !? I guess its safe to say this boat isn't a Westsail.
Plus How bad could the surf had been if just moments before
they had a crew member up the mast And at 2 am !!!!?...). Also
note that the reports claim lighter winds ~ 0-10 knots of wind.
It sounds like they made sure they put together a story that
works well to sue somebody to recover the costs of losing the
boat as they didn't have insurance. PLEASE remember this point,
I think it means something. Yes my heart goes out to these guys,
but still it doesn't add up.
Yeah yeah I know that the New Zealand Safety Authority
wrote up that “the anchor failed when the bolt securing
the two parts of the anchor fell out” and “that
this could reasonably be attributed to the failure of the nut
that secured it” In my opinion, it is very likely that
the investigator’s conclusion is Not right ! (oh......
like that never happened before..he he). The shank is inserted
into a socket on the blade and retained by a stainless steel
bolt with a “Nyloc” style nut. During normal operation
there is no load on this bolt as the substantial socket assembly
takes all the force. There is NO WAY for the shank to come out
of that socket when being pulled in the direction to hold. Spade
anchors are designed to dismantle into two pieces for stowage.
(Very much like a old style Luke Fishermans
Anchor) But you can't pull that shank out in the
direction of holding...with or without that bolt. Don't believe
me, just go to a boat show or a chandlery and see how the shank
is inserted in the anchor face, there is no way for the anchor
shank to come out of that anchor face while anchored or while
the chain rode is still attached....its impossible.
Something sounds very fishy here and I'll say
it right here. Possibly the nut, bolt and blade were removed
after the grounding. Reading further into the story apparently
no attempt was made to recover the anchor until three days after
the grounding. During this time somebody could have removed
the blade. In fact wouldn't someone have actually pulled in
the anchor rode **immediately** to try and kedge the boat. I
know I would have! They would have immediately made comment
about the anchor losing its face. Why did it take 3 whole days
to get the anchor? The FIRST thing I would have looked at would
be the anchor line. Why not pull it in if all there is left
is a shank and why was it "buoyed"?.....Something
sounds fishy here -- very fishy
PS. (Not to mention some other indiscretions
including them only having a rode of rope/chain (when taking
freeboard into account) of approximately 2.88:1)
This seems to be the only account of this ever
happening - take it for what its worth - but I still say its
impossible to lose the face of the Spade anchor if you still
have the rode attached to you boat. The most that I could ever
expect to happen if you lose that bolt is that possibly the
face of the anchor could go askew in relation to the shank.
But losing it - Never.
Now for someone who does some serious cruising
-- Morgans Cloud a boat that does full time Blue water &
"high latitude" sailing really likes their SPADE anchor
saying " We think this anchor is the next best thing to
sliced bread! It sets immediately and holds in almost any bottom,
including thick kelp."
https://www.morganscloud.com/stuff.htm
ps. I have no connection to Spade or the company
or any company that sells marine equipment -- I am just a simple
boater -- but I felt the need to balance out what seems to be
a questionable story
Remember WHY all the posting from the original "Lossee"
He's trying to win some money for the loss of his boat. But
there are WAY TOO MANY INCONSISTENCES !!
If it WAS an endemic failure, I think we would
have heard about more than just one .
Just a Yanks HO (humble opinion)
