Build & Brokerage
Design - UK
Design - Overseas
Dinghy Cat & Tri builders & Suppliers
Offshore and Ocean Racing and Charter
38' Andaman Cabriolet
Building in Thailand
RACHA 1530 Aluminium
(developed from Silkline 1510)
USING A PARACHUTE
ANCHOR Peter Clutterbuck (MOCRA Safety Officer)
Parachute anchors have been used by yachtsmen in the Pacific for decades,
with demonstrated results, but are almost unheard of in the Atlantic.
Over here in Europe, people have read a little about them, but still think
of them in the same category as drogues or sea anchors.
started long distance ocean racing in the Pacific in the 1980s, so have
been familiar with their use and success. I have never heard of a boat
being capsized or lost when properly tethered to a parachute anchor of
the correct size. They work even better on multihulls than monohulls,
due to the wide beam allowing a good bridle angle.
A conventional sea anchor of some 3-6 ft diameter does nothing more than
slow the rate of drift, and has questionable use. If set off the bows,
it has too much sternway to hold the bows to the wind, and a frequent
complaint is that the bows fall off in the troughs of the waves when the
boat and sea anchor are moving towards each other in the wave cycle, and
there is often a lower wind strength reducing the pull on the warp.
The result is that the boat is at the mercy of the next breaker, which
it will often take nearly beam on. I have used sea anchors in this mode,
and read numerous reports, dating from the 19th century, which confirm
this. Off the stern, it is more likely to hold the stern into the waves,
but reduces the ability for the boat to accelerate down a steep face,
and can therefore worsen the impact of breakers.
The answer is to have two distinct devices: a parachute anchor for use
in extreme conditions off the bows, and a drogue for use in heavy (but
not extreme) conditions, off the stern. The drogue should allow a boat
speed of about 10 knots, and there are several designs which increase
drag as boatspeed goes up, therefore allowing a steady speed as crests
and troughs go through. A Para-anchor will stop the boat dead (less than
1/4 knot in a gale), and should never be set off the stern.
The para-anchor must be large: ours if 18 ft diameter for the 43 ft Spirit
of England. For a multihull, its diameter should be around half the beam,
or a third of the LOA. You need a bridle, warp, chain and tripline and
you should rig it up before leaving harbour to get familiar with the set-up.
When you need it, it will be a real emergency, maybe at night, and your
crew will be tired, sick and probably scared: no time for trying to read
In moderate conditions it can be run without the accessories off the bow
on the anchor warp, but it works best with the add-ons, most of which
can be used for other purposes - i.e. fenders, spinnaker gear etc. It
will allow a multihull to survive a hurricane, it allows you to do serious
repairs in heavy weather, it prevents you going the wrong way, and it
gives you room off a lee shore.
Notes on Para-anchor set-up
Ensure this is set up before leaving the dock - you can use the spinnaker
guy lines provided that the blocks on the bows (not snatch blocks) are
strong enough, and the guys long enough. You should have at least 1.5
boatlengths, so you may need to tie extra sheets on. Lead back to winches
and adjust to point the bows into the waves, which may not be in line
with the wind. Ease out a few inches every few hours to alter the chafe
We use 200 ft of 20mm braided nylon anchor warp, anchor chain in the middle
and 400 ft of 16mm para-anchor warp. Smaller boats can use smaller sizes.
The length is governed by the maximum likely sea size, and should be two
wavelengths to avoid snatching or going slack. In non-extreme conditions,
shorter warp (200 ft), and no chain will suffice.
Stainless steel is preferred - the weight also helps deploy the chute
from its bag when you throw it in (it is best not to get the chute out
of its bag on deck as it can blow around).
Prevents the para-anchor diving too deep - ideally set to keep the chute
just below the surface. A large fender on 20 ft of line will do.
We use a 130 ft buoyant partial trip line - water-ski rope is good. A
full trip line to the boat is likely to tangle badly. You can do without
any trip line, but will probably have to wait for quiet conditions to
be able to haul the chute aboard (by one of its lines). A fascinating
aspect of a partial trip line is that you can see that it concertinas
like a snake to about half its length on the face of each wave, clearly
demonstrating wave mechanics: in other words, if you have a short warp
and the boat is in the trough, and the para-anchor on the crest of the
same wave, the warp will go slack. Conversely, when the boat is on the
crest, and the para-anchor in the trough, there will be a violent snatch.
A long warp will keep its tension evenly, especially if the para-anchor
and boat are on different waves.
Allows you to catch the line with a boathook. A small fender is ideal.
Here is an account of its use in adverse conditions
after Spirit of England was dismasted in 1995 in the Atlantic:
We knew the mast was suspect, but were racing, and keen to hold our lead.
We put in a second reef and changed to the staysail as the wind rose through
the night. There was a deafening crash. John yelled "The mast has
gone". I switched on our powerful aft deck floodlight. The mast and
sails were laid over the side. The mast was broken just outside the starboard
hull, the top 40 feet pointing straight down. The seas were now beam on
and rising. Visibility closed in. It was now raining hard. The seas were
rising more. This was not forecast. The barometer was falling. We started
cutting loose what we could with bolt cutters, and an emergency sawknife.
There were over 60 points of attachment between mast and boat.
Most of the running rigging was slashed with the sawknife and the smaller
wires with the boltcutters. At dawn, we continued methodically detaching
lines and salvaging what we could. We had a lot of difficulty releasing
the forestay which was under the load of a half ton of mast pulling it
down, as well as the drag of the sails acting like a sea anchor on the
beam. John got the rotating mast base off, and the boom gooseneck. We
cut the mainsail off with the saw knife and threw it over the side.
John cut through the genoa sheets and the remaining lines, then chopped
the diamonds with the boltcutters and I scrambled clear as the whole lot
sank fast into 16000 feet of water. Spirit started rolling and crashing
from hull to hull in the big beam seas, the outer hulls slamming badly.
The immense strength of the carbon beams kept the boat together. We urgently
needed rest so we could clean up the rest of the wreckage, and get a jury
rig up. It was now time to get the Para-anchor deployed.
First we set a partial 130 foot buoyant trip line with a small retrieve
fender on the end, and a larger fender on the other to buoy up the parachute
and pull its ripcord. We streamed it from a bridle and swivel off the
bows on 200 feet of 20 mm braided nylon. It was all fed out in careful
sequence to weather, and under the starboard hull. I attached the bridle
lines, which were the spinnaker sheets, to the two lines from the bows
already reeved for this purpose. It would not have been possible to reeve
these offshore on the bouncing bows of the outer hulls. When the system
went taught, the weight of the swivel pulled the Para-anchor out of its
bag, and it opened up to its full 18 foot diameter, and pulled the bows
head to wind, with about a quarter of a knot sternway.
The banging and crashing stopped, and the boat became safe as she rose
to the big breakers and was pulled through steadily by the tension on
the warp, which never went slack, and maintained a constant bow-on load.
We lay to this for the best part of three days as the wind blew from the
NNE at Force 6, with the seas at 15 feet. It was too rough to raise a
When the weather subsided, we decided to pull in the para-anchor, and
run off under bare hulls to build a jury rig. Getting the para-anchor
in was a problem, as the wind was still Force 6, and the waves some 12
feet, preventing us going onto the outrigger bows to release the bridle.
John winched in one half of the bridle, allowing me to grab the other
slack half with a long boathook off the bows, and clip it through a bow
snatch block. Then John winched it in until I could reach the trip line,
whereupon I tripped it and we sailed off under bare poles without poles,
or "bare hulls".
If we had not had the para-anchor, the boat could have been badly damaged
under the onslaught of seas taken on the beam over three days of heavy
North Atlantic conditions. I am happy to say that our new carbon mast
has been trouble-free in five years of offshore racing, having sailed
through more Atlantic gales, and we have not had occasion to use the parachute
anchor since. However, it is very reassuring having it on board should
an emergency arise.