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Article
by Tor Pinney
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ATTENTION CRUISING
SAILORS: THIS COULD SAVE YOUR LIFE!
CAPT'N TOR'S LAST CHANCE TRIP LINE
© 1990 Tor Pinney - All
Rights Reserved
Anyone who has ever sailed offshore shares a common
dread: falling overboard and helplessly watching the boat sail away. No
matter how many shipmates you have resting belowdecks, if
you're alone on deck, you're at risk just as much as the single-handed
sailor. No one will hear you cry out.
Most passage-makers take the obvious precautions:
maintaining pulpits and stanchions with continuous lifelines around the
yacht's rail; running jack lines along the side decks to clip on the
safety harness that we wear most of the time. Some even tow a so-called
"safety line" astern. Still, every so often we hear of the
ultimate tragedy: Some sailor has fallen overboard and been lost at sea.
I've single-handed quite a bit and, over time, I gave
the problem some serious consideration.
Now, I'd like to share an idea I came up with, tested and have used for
years because, if properly installed by more sailors, it could save at
least some of those lives. It's a simple, inexpensive
lone-sailor-overboard rescue device that I call my Last Chance Trip
Line.
If you were to grab onto a simple "safety
line" trailing behind a boat sailing at five or six knots,
you'd have a tough time trying to haul yourself forward on it while being
dragged through the
water. Fully clothed, it would be nearly impossible. Eventually, you'd
tire out and let go. But the
result of grabbing the Last Chance Trip Line is that the boat will almost
immediately come to a
near or complete halt, giving the man overboard an opportunity to easily
regain the ship. It will
work aboard any boat, providing one last chance to save yourself if the
nightmare ever comes
true and you find yourself overboard and alone while underway.
The Last Chance Trip Line consists of about 200' of
1/2", yellow polypropylene line (i.e., floating line), a Styrofoam
ball float like the kind lobstermen use to mark their traps, at least two
5-ft. pieces of 5/16" or 3/8" elastic shock cord with a plastic
hook at one end, and one or two
1/2" blocks on lanyards. It'll also require a bit of trial-and-error
experimentation because precisely how this equipment is assembled will
vary from boat to boat. Here's the basic idea:
The buoyant trip line, which has half hitches tied in
every 6 feet or so for better gripping, trails behind the boat while
voyaging offshore. The Styrofoam float marks the "bitter end"
(pun intended!), while the inboard end is led in such a way that increased
drag on the trailing line will disengage the self-steering mechanism or
engine throttle. In the case of a vessel under sail, it will then steer
the boat up into the wind to stall it. Once you've worked out the right
adjustments for your boat, you can set up your Last Chance Trip Line in a
couple of minutes anytime you're heading out to sea.
The normal line tension created by towing is countered
by the shock cord, hooked to a bight in
the line two or three feet abaft the stern rail. Because of this, the
inboard portion of the trip line remains slack until the weight of a
dragging person overcomes the shock cord to exert force on
the inboard line.
Now let's consider various ways in which this can be
applied to accomplish our goal of stopping
the boat, beginning with disconnecting autopilots:
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The external autopilot on a sailboat's
tiller (Figure 1) is the easiest to disengage - all it takes is a
light lifting motion to jerk its drive arm off the tiller
attachment knob. To do this, the inboard end of the trip line runs
from the bight (a) to which the shock cord (b) is attached, over
the pushpit rail (c) to give it some height, then through a block
(d) lashed to the tiller immediately aft of the attachment point
of the autopilot drive arm. The block hangs by its lanyard just a
few inches below the tiller. Finally, the trip line runs across
the cockpit and slightly forward to the lee rail where it is tied
to a strong attachment point (e) which is only slightly higher
than the tiller. This end is secured, taking up almost all of the
slack in the trip line, but still allowing the shock cord to take
the entire pulling force of the line trailing aft.
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Because of the shock cord, the inboard end of the line remains slack
(but just barely so!), exerting no force on the autopilot or the tiller.
But if someone in the water were to grab that trip line and drag behind
the boat on it, the increased line tension would stretch the shock cord,
putting tension directly on the trip line inboard of the bight. The taut
trip line will raise the block, lifting the autopilot drive arm off the
tiller, and it will simultaneously pull the tiller to leeward. The boat
will head up, luff the sails, and stall. If the jib is trimmed for
windward sailing, it will likely back, heaving the boat to. If the sails
are trimmed for a reach, they'll likely continue luffing even it the boat
falls off again. In any case, the man overboard has time to pull himself
easily to the stalled boat.
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Disengaging autopilots on boats with wheel steering
requires variations of this principle, depending on the autopilot
system used and how it is installed. (See Figure 2) It may be
necessary to run the trip line through a block on a short lanyard
(a) tied to the autopilot's clutch knob so that it will, under
tension, pull out the knob to disengage the self steering. The
same principle applies to both wheel-hub clutches and to
foot-level clutches such as the popular Autohelm and Navico units.
From the clutch block, the line passes through a second block (b)
stationed to port or starboard of the helm, and then across to the
wheel's rim (c) in order to have the ability to turn the boat. If
the second block is on the lee side of the cockpit, the line's
attachment point along the rim will be at the farthest (windward)
spoke BELOW the wheel's horizontal center plane. If the block is
on the windward side, the line must be led to pull on the farthest
(leeward) HIGH spoke (as illustrated in Figure 2) in order to turn
the boat into the wind. Again, the shock cord aft holds the
inboard line section barely slack until a strong pulling force is
applied to the outboard end of the trip line.
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On some boats a line-and-lanyard system might be easier to use
(Figure 3). Simply tie a second bight into the trip line, anywhere
between the side block and the shock cord's bight. Lanyards, or
short lengths of shock cord, can be easily led off a bight to pull
clutch knobs and switches. Whatever directional pull it takes for
a trip line to disengage the self-steering unit and/or head your
boat into the wind can be engineered with blocks, shock cords,
lanyards and a bit of ingenuity.
With internal autopilot units, a lanyard coming off the trip
line may be led so that it flips a toggle switch that turns off
the unit, allowing the trip line to turn the helm. Better still, a
tug on the trip line could be rigged to activate an electric
over-ride switch that will cause the autopilot to steer the boat
sharply to windward. The same switch could also activate an alarm
to arouse sleeping crew. But keeping it simple and self-reliant is
probably best. |

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Windvanes pose no problem once you grasp the general idea of the Last
Chance Trip Line. But rather than disengaging the windvane, the trick here
may be to use it to steer the boat into the
wind.
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On a Monitor windvane (Figure 4), the trip line passes first
through a block on a lanyard (a), then between the rods holding
the vane's lead counterweight which is below the wind paddle (b),
and finally ties to a convenient part of the windvane's framework
(c) or ship's hardware. Once again, the shock cord (d) is attached
to the trip line at the outboard bight, in this case just aft of
the block. Because the shock cord keeps tension off the inboard
section of the line, the windvane is free to operate unimpeded -
until someone pulls on the trip line. Then the cocked windvane
will steer the boat up into the wind, stalling her. By having the
block on a lanyard, it's easy to shift its position and experiment
to determine the correct angle of pull on the windvane's
counterweight. This changes as the windvane paddle is swiveled for
different points of sail. In this manner, you control which way
the windvane will turn the boat when the trip line is pulled.
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Lastly, stopping a boat that is motoring is as simple as rigging the
line or lanyard to pull back the throttle, or the throttle and gear shift
levers, or the engine cut-off knob. After reviewing the above variations
of leading and balancing the trip line, an engine-stopper should be easy
to figure out aboard your own boat.
As a boat's sailing speed increases, it may be necessary to adjust
(tighten) the shock cord. Otherwise, the increased drag on the line could
overcome the shock cord and trip the system. The tension of the shock cord
is adjusted from the inboard end so that the cord continues to barely
overcome the pulling force of the dragging trip line. But beware! Too
short a shock cord will not have enough stretch left in it to allow the
trip line to work when needed. When adjusting for increased boat speed,
it's generally better to re-tie the shock cord further forward rather than
to shorten it. If this still isn't enough to overcome the drag or if the
shock cord is stretched nearly to its limit, then double up on the shock
cord with a second piece. Ultimately, the shock cord must absorb the
towing force with elasticity to spare.
Your Last Chance Trip Line system is easy to test - without throwing
your mate overboard. Just reach over the stern rail, beyond the shock
cord, and haul firmly and steadily on the line. A safer alternative is to
tie a bite in the line just abaft the shock cord attachment point, slide
the end of a boat hook into it, and push to create the drag effect. If the
ultimate result is that the boat comes to a halt, you got it right!
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Once the trip line has done its job and allowed the lone sailor to pull
himself back to the boat, he still must be able to climb aboard
unassisted. A permanent ladder or steps installed at the transom, or some
certain means for a swimmer to pull down a stern boarding ladder, will
ensure a happy ending to the man overboard self-rescue.
By the way, the polypropylene trip line should be stored out of the sun
when not in use. Otherwise, it will deteriorate rapidly from exposure to
ultra-violet rays.
You might argue that at night the trip line could be difficult to find
quickly enough for a frightened person grappling in the dark. Or that it's
useless to an unconscious man overboard. And that nothing takes the place
of exercising proper caution to ensure that crewmembers don't fall off in
the first place. You'd be right. The Last Chance Trip Line is no
substitute for wearing your safety harness while on deck, nor is it a 100%
guaranteed lifesaver in every situation. But for the lone mariner who
suddenly finds himself overboard while the boat sails on without him, the
Last Chance Trip Line is a whole lot better than the alternative - no
chance at all.
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End ~
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