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SEA ANCHOR FAQ'S
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(actually just answers)
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The following documents are in Adobe PDF format.
You will need Adobe
Acrobat Reader to view these files.
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Bridling
MULTIHULLS
All Multihulls MUST use a bridle to both hulls (abase).
Each leg should be a minimum of two and a half times the beam
of the boat.
The overall scope of rode, including the bridle length, should
be about 11 to 12 times the LOA or longer.
The bridle legs MUST be attached to both hulls. WARNING -
Some catamarans have a centrally located anchor roller situated
midbeam on the weakest part of the boat - the aluminum crossbar
that supports the trampoline. On these boats leading one of
the bridle legs there MUST NOT BE DONE. It is not braced like
a mast and attaching to it can lead to failure of the crossbar,
capsize and loss of life. We learned this because someone
did just such an attachment (against the instruction manual)
which lead to failure of the crossbar, capsize and LOSS OF
LIFE!!! See page 10 of the PARA-TECH Sea Anchor Instructions.
ATTACHING BRIDLE LEGS
NOTE - Make sure cleats or pad eyes have substantial backing
plates.
If you are cleating off the bridle legs you MUST use substantial
chafe protection, be prepared to check for chafe often and
let some rode out if experiencing chafe.
You can shackle the bridles to the hulls using thimbled rode
ends and shackles. This eliminates the need for chafe gear
provided the bridle legs are not rubbing on any part of the
boat.
You can use snatch blocks on one or both bows as fairleads
routing the bridle legs (make sure they are long enough to
reach) back to solid connection points (cleats, etc.). One
bridle leg could be fixed, or both adjustable which will allow
you to change the angle on the bow for a more comfortable
ride. Be aware of chafe between the snatch blocks and the
connection points and check for it often.
BRIDLE JUNCTION
There are three ways of assembling the bridle/main rode junction:
Thimbles in the ends of each bridle leg and the end of the
main rode - make sure you use one shackle on each bridle leg.
DO NOT attach all three thimbled ends to one shackle as the
thimbled ends will bind against each other. This setup allows
flexibility in that you have three ropes to work with if you
need them for other uses.
Thimble in the end of the main rode and a "Y" bridle
which is attached to the main rode with one shackle. This
type of bridle is best made with single braid rope as it can
be threaded through itself and can not separate.
DIRECT SPLICED BRIDLE
This is a main rode/bridle as one unit. The main rode
goes from the Sea Anchor to the boat and one bridle leg is
spliced into the rode at the bridle leg length from the boat.
Imagine a huge dock loop which has been cut in two. Again,
this type of bridle setup is best made with single braid rope.
MONOHULLS
Lin and Larry Pardey, in their book "STORM TACTICS"
advocate the use of a bridle to hold the boat in a hove-to
attitude for greater stability and ride comfort. We believe
that securing the boat at some angle to the weather can make
a difference in how the boat rides and the degree of comfort.
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Use Of Chain
WITH SEA ANCHORS
We recommend use of some chain between the Sea Anchor
and the boat.
CHAIN AT THE SEA ANCHOR
If you are planning on cleating the main rode to your boat
(with SUBSTANTIAL chafe protection) then we recommend using
a short length of chain at the Sea Anchor to aid deployment
and create some catenary effect. Chain at the Sea Anchor helps
keep the Sea Anchor down. During slack cycles the chain causes
the Sea Anchor to swing down and maintain some tension in
the rode.
MID-SCOPE CHAIN
Although our instruction manual illustrates chain mid-scope,
input from the field (to the Drag Device Data Base by Victor
Shane) suggests it does not have the effect we had believed.
One report we received tells of a 40' sloop in a hurricane
with 200' of rode, 40' of chain with a 45# CQR mid-chain and
then another 200' of rode. The report is that the rode and
chain were straight and the anchor was thrashing about the
chain. Placing chain mid-scope is the busiest place, requiring
thimbles in the rode ends and shackles to join the chain to
the rode. For these reasons we tend to lean away from mid-scope
chain.
CHAIN AT THE BOAT
This is where chain can provide the most benefit. It
prevents the rode from chafing through (which is our biggest
concern). You can let out a few feet in moderate conditions
to well over 100' in severe conditions.
There are a few things you need to be aware of:
Remove the anchor from the end of the chain - if you are
unable to remove the anchor you MUST use a short length of
chain as a "stand off" to keep the anchor flukes
away from the rode because an anchor which is thrashing about
could chafe through the rode with its flukes.
The chain MUST be snubbed to the deck cleats to off load the
windlass. We carry Stainless Steel Chain Grabbers for this
purpose (they fit 5/16" to 1/2" chain).
Once you are set on the Sea Anchor it is virtually impossible
to adjust the amount of chain which is out so you must determine
the sea conditions and let out the appropriate amount when
the Sea Anchor is initially set. (See the section "Bridling
with Chain").
The down side to using chain at the boat is that the chain
can do damage to the chocks, bow roller, etc. but we believe
the trade off of not having to be concerned with the rode's
chafing through is worth the possible damage.
CHAIN/RODE CONNECTIONS
We are not in favor of spliced chain/rode connections.
We prefer thimbles in the ends of the rode and shackling the
ends to the chain. This is a little problematic as the "weak
link" is often the size of the shackle screw pin. A shackle
with a screw pin which will fit through the chain link may
often be weaker than the chain and the rode. The proper size
shackle may have a screw pin which is too large to fit through
the chain link. It is important that the strength of all components
be as close as possible to matching. One way to get past this
is to use the proper sized bow shackle attached to the rode
and attaching that shackle to the chain via a Titanium "D"
Shackle. This is a little busier but the bow shackle can be
attached to the rode and moused leaving just the titanium
shackle to be attached to the chain.
CHAIN & DROGUES
It is well established that the use of a length (10 to
15 feet) of chain between a Drogue and the rode will help
keep the Drogue down and improve its performance.
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Rode
We have always advocated NYLON rode for use with PARA-TECH
Sea Anchors due to its ability to stretch and absorb energy.
Recommended sizes are in the PARA-TECH Sea Anchor Instructions
and are based on feedback to the Drag Device Data Base by
Victor Shane. You can use a larger size than recommended but
you should not go smaller.
ALWAYS buy the best
rope you can possibly afford.
REMEMBER, your life may depend on it!!!
MAIN TYPES OF ROPE
3-Strand Twisted - This is by far the most common
type of rope construction and the least expensive as virtually
everyone makes it. The down side is that some manufacturers
use the cheapest yarn to keep the price competitive. The worst
part of 3-strand is that it has a tendency to twist or unlay
when under load. This twisting and untwisting has been known
to generate heat which weakens the rope. Also, this twisting
and untwisting makes the rope an unruly mess when you try
to stow it after it has been loaded as it wants to twist,
knot and hackle. NOTE: A good swivel can absorb some of these
torsional loads during slack cycles.
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Double Braid - This is also a very common construction
and generally a little stronger than 3-strand twisted. It
does not twist when under load but has less stretch due to
its construction. Having inner and outer components the two
parts can generate friction between them which can weaken
the rode. It is generally more expensive than 3-strand twisted.
If the core (inner section) herniates, or bulges outside the
outer part, the rope must be discarded or the damaged part
cut out and the ends re-spliced.
Single Braid- The least common construction - but we
believe it is the best construction for use with Sea Anchors
- it does not twist under load or generate heat during load
and unload cycles and has good stretch characteristics. It
is usually the most expensive rope you can buy.
Nylon Yarn- Over the years we have learned that there
is a significant difference in the various types of nylon
yarn used to make rope. Ropes made from Type 6-6 yarn are
FAR superior to ropes made from Type 6 yarn both in their
elasticity and their resistance to ultraviolet degradation.
ASK your rope supplier what yarn their rope is made from -
DO NOT tell them what you are seeking - MAKE THEM TELL YOU
WHAT IT IS MADE FROM. Otherwise they will just say it's made
from the yarn you want. PARA-TECH ONLY supplies single braid
rope made from Type 6-6 yarn.
RODE LENGTH
For severe storms we recommend 10 to 15 times the LOA. For
overnight layovers in moderate conditions very short rodes
have been used, however it is EXTREMELY important that if
you use a short tether you pay particular attention to the
"Hazards of Wave Particle Rotation" section in the
Sea Anchor instruction book.
3 Lengths - Short, Intermediate, Storm
Short - A short rode is one which is within 1/3 of
a wave phase - if the distance between crests is 100' then
a short rode would be about 33' or less. There is little chance
of enough energy build up to break the rode or damage the
Sea Anchor. The rode should be no longer than this 1/3 wave
phase. This length is commonly used for drift fishing in light
to moderate conditions and fairly flat seas. This distance
is more critical in seas where there is a definite running
swell as you can easily get into the intermediate length requirement.
Intermediate - Rode length of 35' to 300'. Within
this range of rode length it is critical that the boat and
Sea Anchor be "IN PHASE" - BOTH are on the crest
and in the trough at the same time. If not in phase the boat
and Sea Anchor will converge (move towards one another), creating
slack in the rode and then diverge (move away from one another).
When they diverge they are accelerating away from one another
and when the slack is taken out of the rode something has
to give. If the rode is long enough (storm length) it should
have sufficient stretch to absorb the energy of this acceleration.
If the rode is not long enough any one of the following can
occur - the Sea Anchor blows a panel (preferred occurrence
as the Sea Anchor will still work), the rode will break or
a cleat will fail (you lose your hold on the sea). This length
is generally used on overnight layovers and when fishing.
It is the most critical rode length to use. Again, pay particular
attention to the "Hazards of Wave Particle Rotation"
section of the instruction manual.
Storm - In severe storms there are three main reasons
for the 10 to 15 times LOA length:
There is so much tension on the rode that to be constantly
adjusting the length to be in phase with the waves is a practical
impossibility.
In a severe storm the seas will be confused with irregular
swells and the long rode length will tend to mitigate the
effects of being out of phase.
The long length of NYLON rode provides for some give or shock
absorption in the
system which leads to less stress on the Sea Anchor, rode
and attachment hardware.
PARA-TECH RODE/STOW DEPLOYMENT BAGS
These bags are designed to make rode deployment as easy as
possible. The rode is attached to the Sea Anchor and the boat
and the bag is tossed overboard with the Sea Anchor where
the rode deploys automatically. The rode passes through the
bag and the bag is held captive to the system.
One of the considerations in using Rode Stow/D'bags is the
amount of rode in each bag. Many cruisers are couples and
putting 400' of 3/4" rode in one bag would make the bag
weigh over 60 Lbs. Imagine the stronger person being injured
and the weaker person having to deploy the Sea Anchor. With
this in mind we generally will split the rode into two lengths
which must be shackled together. This is a little busier but
is more manageable for a person with limited strength.
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Trip Lines
There are many opinions with respect to the use of trip lines
to recover Sea Anchors.
Some prefer to use a full trip line which comes all the way
back to the boat. These users are usually fishermen who use
their Sea Anchors as a tool for overnight layovers and persons
who actively use their Sea Anchor.
Some prefer to not use any trip line at all. Usually with
smaller Sea Anchors.
Still others prefer a "partial" trip line which
floats free and must be motored up to to recover the Sea Anchor.
A trip line is a line attached to a PARA-TECH Sea Anchor
as an extension of the Float Line (which is an integral part
of the Sea Anchor and goes from the apex [top center] of the
Sea Anchor to the surface). A float (usually a large fender,
referred to as the Primary Float) is attached to the Float
Line and this float controls the maximum depth the Sea Anchor
is allowed to go. Note that when under load the Sea Anchor
will ride virtually at the surface. During recovery, when
the Sea Anchor is unloaded, it hangs like a jellyfish by the
float and Float Line. Without the float on the end of the
Float Line the Sea Anchor could hang upside down in an open
position. This is VERY DANGEROUS as the Sea Anchor can literally
pull the bow under if allowed to open in this attitude.
PARTIAL TRIP LINES
We recommend the use of at least 20' (preferably 50 to 100')
of 1/4" to 3/8" polypropylene line for a partial
trip line. You should attach something that floats to the
end of the trip line. This allows you to fetch up on the trip
line and still be away from the Sea Anchor. The 20' minimum
is so when you get to the trip line you are lifting a limp
line onto the deck from the waterline. This has to do with
LEVERAGE. Without a trip line you will be lifting the float
and float line, with everything hanging below it, from the
waterline to the deck. A trip line allows you to get the line
on deck before any lifting is done. Partial Trip Lines are
easier to deploy but recovery requires motoring up to the
Trip Line in order to recover the Sea Anchor, which can be
challenging in somewhat turbulent conditions.
FULL TRIP LINES
A full trip line goes from the Primary Float all the way back
to the boat. Use of a Full Trip Line makes recovery very easy.
You take all the slack out of the Trip line, cleat it off,
then let out the main rode which will automatically "trip"
the Sea Anchor. It's then a simple matter of pulling in the
Sea Anchor by the Trip Line. It does take a little more care
in deploying a Sea Anchor with a Full Trip Line. Some of the
early pioneers of Sea Anchor use, John & Joan Casanova,
used a full trip line for Eighteen Years while cruising on
two different multihulls and deploying their parachute [Sea
Anchor] in storms of every description with no difficulty.
If not using a trip line, the common practice is to literally
pull the boat to the Sea Anchor. With 6' and 9' Sea Anchors
it is usually not that difficult but with larger Sea Anchors
(and thus larger boats) it becomes increasingly more difficult
and you risk equipment (rode, cleat, etc.) failure when the
Sea Anchor and boat get out of phase with respect to wave
particle rotation (see hazards of Wave Particle Rotation in
the PARA-TECH Sea Anchor instructions).
BEING TAKEN UNDER TOW
If you are laying on a Sea Anchor because your boat is disabled
and you are about to be towed, a Trip Line will make being
taken under tow far safer. You can direct the tow boat to
the Trip Line. They will be upwind of you and several hundred
feet away, virtually eliminating any chance of collision.
They would pull the Trip Line on board, followed by the Sea
Anchor and the rode, cleat the rode and take you under tow.
If you are using a Full Trip Line attach a float to the end
and toss it over for them to fetch up on.
PARA-TECH TRIP LINES
Our Partial Trip Lines are 100' polypropylene lines in their
own stow/deployment bags with integral float. The bags are
red for visibility and can be used as a heaving line if needed.
They are also available in longer lengths but 100' is adequate.
Our Full Trip Lines are 1/4" Nylon (to stretch as the
rode stretches during wave cycles). They come in their own
stow bag. Length is determined by Sea Anchor size and rode
length.
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Surplus Parachutes
As Sea Anchors
When we started in the Sea Anchor business the only "Sea
Anchors" we sold were government surplus 24' and 28'
personnel parachutes which we set up for use as Sea Anchors.
These parachutes performed adequately but over time we found
their durability to be poor. Our first customers were the
local sport fishermen who used them mainly for overnight layovers
and wore them out regularly, sometimes as often as twice a
season. Durability, cost and availability lead us to make
our own parachutes specifically for use as Sea Anchors.
Occasionally we are asked about surplus parachutes for use
as a Sea Anchor. There are many different parachutes out there
and we are familiar with very few. This is not to say that
none of them are usable as a Sea Anchor. If we are not familiar
with a particular one we are asked about we won't offer an
opinion as to its suitability. If it is sent to us we can
evaluate it and offer our opinion. Many parachutes can be
altered for use as a Sea Anchor but the main question is durability.
We have no objection to setting up a surplus parachute as
a Sea Anchor but we WILL NOT be responsible for the structural
integrity of any particular parachute. The parachute may hold
enough water to hold your boat but not be durable enough to
endure the duration of a storm.
WARNING
From time to time "rock crawlers" (people who crawl
out from under their rock, rip people off and then crawl away)
offer surplus parachutes representing them as "sea anchors"
... some of these rock crawlers claim "one size fits
all". DON'T YOU BELIEVE IT!!! One of these rock crawlers
had the nerve to claim that the sea anchors he was selling
were government surplus PARA-TECH sea anchors. THEY WERE NOT!!!
We got one and they were made of mosquito netting with no
structural integrity at all. They actually were flare parachutes
left over from the Vietnam War. That rock crawler is located
in Annapolis, MD. If you have one contact us IMMEDIATELY -
DO NOT USE IT.
BUYER BEWARE - If you are not sure what you have purchased
please give us a call, your safety and well being is our NUMBER
ONE concern
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"Spinning"
Sea Anchors
1. "Spinning" Sea Anchors - We have heard stories
of the Float Line and Trip Line becoming twisted together
and tangling, supposedly because the Sea Anchor was "spinning"
in the water. While surplus parachutes are built in a way
that can lead to rotation, PARA-TECH Sea Anchors are manufactured
in a way that any rotation is "built out" and underwater
video of a PARA-TECH Sea Anchor being towed has shown there
is no rotation.
2. Float Line & Trip Line Twisted Together - There have
been reports of the Float Line and Trip Line becoming twisted
together. While this has been credited to the Sea Anchor "spinning"
our observation is that the Primary Float is the culprit.
All three items (Float Line, Trip Line & Primary Float)
join at the same point and there is no tension on the Trip
Line. Surface action on the Primary Float causes it to spin
around and, with no tension on the Trip Line, the Trip Line
gets wound around the Float Line. Our solution is to attach
a small swivel to the end of the Float Line. The Trip Line
is attached to the same side of the swivel as the Float Line.
The Primary Float is attached to the free side of the swivel,
separating its motion from the Float Line/Trip Line.
3. Deployment Bag caught in Lines - On PARA-TECH Sea Anchors
built prior to 1998, the Bag could rise to the surface. On
the surface the Bag would fill with water. In breaking seas
the water filled Bag could be subject to wave crest capture
and be thrown over the Sea Anchor and into the lines. On all
Sea Anchors built after 1998, there is a ring attached to
the Float Line about two feet from the apex of the Sea Anchor.
This ring holds the Bag well below the surface and out of
the wave crest.
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Strengths Vs Loads
and Holding Power
We often hear comments referring to the strain on the rode
when tethered to a Sea Anchor in severe weather. These comments
all have the same thing in common - the strain on the rode
is HUGE. But just how high is the strain?? We believe the
strains appear to be higher than they really are. WHY??
APPEARANCES CAN BE DECEIVING
Put a 1,000 pound load on a 10,000 pound tensile strength
rope and the rope will appear to be very close to breaking
when in reality it is loaded to only 10% of its strength.
Commercial fishermen have used surplus 24' and 28' parachutes
for years. We know from our own tug testing that the 24' parachutes
will fail at a load of 4,000 pounds. Call it 5,000 pounds
for a 28'. Those fishing boats are in the 50 to 60 foot range
displacing from 45,000 to 85,000 pounds. Data Base File S/P-2
is from a 65', 85,000# F/V on a 28' parachute in 18' seas
and 45-55 Kt. winds. The loads COULD NOT HAVE BEEN 5,000 pounds
or the parachute WOULD HAVE FAILED (see #3 below). Another
boat - 50' LOA and 70,000# regularly used 1/2" rode (7,000#
Tensile Strength) with a 28' (5,000#) parachute.
From wind load charts in various publications a 60' power
boat in 42 Kt. Winds generates 4,000# of pull and 8,000# of
pull in 60 Kt. Winds Assuming these numbers are accurate and
adding anything at all for wave forces then the 28' parachute
in S/P-2 should have failed in 55 Kt. Winds but it didn't
Equivalent PARA-TECH Sea Anchors are two to four times the
overall strength of surplus parachutes. PARA-TECH system recommendations
are based on the premise that the Sea Anchor is the "weak
link" and when extreme stresses are experienced (like
a wave breaking over the wheel house of a fishing boat) the
Sea Anchor will blow a panel to relieve the stress but still
hold the boat when a surplus parachute would fail totally.
PARA-TECH RECOMMENDATIONS
Our recommendations are based on years of input to the
Drag Device Data Base by Victor Shane.
We have made changes to our products and recommended components
because of this input. Our general rule of thumb is when in
doubt go to the larger size - Sea Anchor, rode, hardware,
etc. We look at the LOA of the boat first then the weight
or displacement then the type of boat (S/V, P/V, Multihull,
etc.). For offshore use in potential heavy weather with breaking
seas the minimum size we recommend, regardless of boat size,
is 12'. Any smaller Sea Anchor would likely be caught in the
crest of a breaking wave and be completely tumbled and collapsed
(See Sea Anchor Sizing Considerations).
The following chart illustrates the "holding power"
of PARA-TECH Sea Anchors. There is NO WAY any Sea Anchor could
take these kind of loads and the displacement numbers are
best viewed strictly with respect to the amount of water a
parachute Sea Anchor displaces - they have no bearing as to
the strength of the Sea Anchor. In the Sept., 1999 issue of
Yachting World we were daises by a contributor who experienced
a less than satisfactory ride on an 18' PARA-TECH Sea Anchor
while in a storm aboard his 55', 50,000# ketch. Seems the
author and W.W.II's editors overlooked a small point. AT NO
TIME has PARA-TECH recommended an 18' Sea Anchor for a boat
over 50' LOA. In the chart note that the 18' Sea Anchor has
has less than 50% of the holding power of a 24'.
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Sea Anchor Size
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Water Displacement
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Recommended
Boat LOA
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Boat Displacement
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6 Foot
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2,400 Lbs.
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Under 20 Feet
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to 4,000 Lbs.
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9 Foot
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9,900 Lbs.
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Under 25 Feet
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to 8,000 Lbs.
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12 Foot
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23,500 Lbs.
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25 to 33 Feet
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to 12,000 Lbs.
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15 Foot
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45,500 Lbs.
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30 to 40 Feet
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to 25,000 Lbs.
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18 Foot
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79,400 Lbs.
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35 to 48 Feet
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to 40,000 Lbs.
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24 Foot
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188,000 Lbs.
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40 to 90 Feet
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to 95,000 Lbs.
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32 Foot
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446,000 Lbs.
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70 to 120 Feet
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to 200,000 Lbs.
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40 Foot
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871,000 Lbs.
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120 to 150 Feet
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to 300,000 Lbs.
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Sea Anchor Sizing Considerations
OFFSHORE STORM CONDITIONS
The MINIMUM size Sea Anchor we recommend for this application
is our 12 foot for the following reason:
WAVE CREST CAPTURE
In confused or breaking seas the breaking part of the wave
can extend 8' deep or more. A Sea Anchor smaller than 12 feet
caught in this breaking crest will be fully captured and tumbled
causing the Sea Anchor to completely lose its grip on the
sea. With the Sea Anchor no longer holding, the boat will
fall off and be in danger of being rolled. By using a LARGE
DIAMETER parachute Sea Anchor of at least 12 feet in diameter,
if the seas are breaking 8' deep the lower 4' of the Sea Anchor
will remain in the non breaking part of the sea and will maintain
its grip on the sea. Once the breaking wave passes the Sea
Anchor is then able to reset itself and fully hold the boat.
This is the reason we advocate the use of LARGE DIAMETER parachute
Sea Anchors.
NOTE: ALL Sea Anchors, when under load in storm conditions,
will ride right at the surface. Anyone who says otherwise
is not being accurate.
OFFSHORE IN MODERATE CONDITIONS
Overnight layovers when fishing, etc. - you can follow the
sizing guidelines on the Sea Anchor page.
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The Drag Device Data
Base
Following a successful solo crossing from Santa Barbara to
Honolulu and back in 1979 aboard his 24 Foot trimaran"PROVIDENCE"
and aided by a surplus parachute as a Sea Anchor, Victor Shane
set out to catalog and disseminate accurate information about
the use of Sea Anchors and Drogues. Thus was born the Drag
Device Data Base (DAB). An added impetus was the 1979 FASTEN
tragedy where several boats and lives were lost - lives and
boats that could well have been saved had they been aware
of modern drag devices.
Now in its fourth edition, completely revised and updated,
we consider the DAB to be the best work available on the subject
of offshore drag devices - Sea Anchors and Drogues.
Because of the real world contributions from drag device
users to the DAB we have made refinements in our Sea Anchors
to make them more "user friendly" and have also
refined our sizing and rigging recommendations.
The DAB is an ongoing work and we are constantly in touch
with the author to swap information. Every PARA-TECH drag
device goes out with a DAB Response Form - we want to know
what works the best and where improvements can be made.
The DDDB is a worthwhile addition to your library of cruising
books and is available from us for $36.95.
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Supplemental Instructions
For using your PARA-TECH Sea Anchor for overnight layovers-
fishing trips, etc.
RODE LENGTH
For storm use we recommend a length of at least 10 times the
LOA of the boat. This length is to mitigate the effects of
being out of phase with respect to the HAZARDS OF WAVE PARTICLE
ROTATION (see pg. 13 of the instruction manual). In confused
seas the phase will not remain constant, which would make
it necessary to constantly adjust the rode length. But the
strain on the rode in such conditions so high that it is virtually
impossible to make such adjustments so adjusting the scope
is generally done because of chafe. This is not the case in
moderate conditions where the strain on the rode is much lower.
In any case it is easiest to let our additional rode to get
"in phase".
On overnight layovers in moderate conditions a much shorter
rode can be used. However, you MUST pay particular attention
to the HAZARDS OF WAVE PARTICLE ROTATION and make sure the
Sea Anchor and Boat are "in phase". If conditions
deteriorate and a longer rode is necessary you need to be
prepared to let out as much as 10 times the LOA of your boat,
or more. This may entail shackling a second or third rode
to the primary rode.
TRIP LINES
The use of a FULL Trip Line (all the way back to the boat)
for overnight layovers will make recovery much easier. Extra
care should be taken during deployment to keep from getting
the Trip Line wrapped around the Sea Anchor. The Full Trip
Line should be 1/4" Nylon and at least the length of
the rode plus the size of the Sea Anchor. Once the Sea Anchor
is set, excess slack should be taken out of the Trip Line
but it should not be tight.
RECOVERY WITH A FULL TRIP LINE
The easiest way to recover your Sea Anchor with a Full
Trip Line is to take all the slack out of the trip line and
cleat it off. Next let out the anchor rode. As the rode is
let out the Sea Anchor will "trip" (turn upside
down) and collapse on itself. It is then a simple matter to
pull the Sea Anchor in via the Trip Line.
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