Bill Lee on Alternate Steering Methods - No Rudder Needed?

Excerpt from Transpac Questions and Answers
Bill Lee, Wizard Yachts Ltd.

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Q: My boat has a long graceful stern overhang with a small traditional transom. I
see no way to fit an emergency rudder to meet the emergency steering
requirement of section 4.15.

A: The actual requirement is “alternative methods of steering” of which an
emergency rudder is only one.

Another approach is to permanently mount an extra pin for the spinnaker pole on
the stern close to centerline with a universal toggle. In case of rudder loss, the
spinnaker pole is fitted on to the pin. 4 controls are needed, that being port,
starboard, up, and down. For port and starboard, run lines from the outboard end
of the pole through snatch blocks and to the cockpit winches. For up, swing a
spinnaker halyard around the mast and attach it to the end of the pole. For down,
attach a suitable amount of anchor chain to the end of the pole. You are not
going to keep seriously racing with this system, but if your main rudder breaks
you are probably done racing anyway. Two benefits of this system are that it is
not prone to breakage, and there is little risk of loosing the parts during
installation.

Regardless of what alternative method of steering are chosen, it is imperative
that the owner and crew have tested the system away from the dock and are fully
confident that it will in fact steer the boat.

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Bill Lee, the Fast is Fun Wizard. Legendary Santa Cruz boat builder whose outof-
the-ballpark successes include the record-setting Merlin as well as numerous
other boats optimized for Pacific Coast conditions. Currently matches boats to
people from his Wizard Yachts office in Santa Cruz

Emergency Rudder Design Guidelines

by Paul Kamen PACIFIC CUP 1998 - Preparation Seminar No. 1

Emergency Rudder Design and Construction

Berkeley Yacht Club February 28 1998

DESIGN REQUIREMENTS:

• Cheap and easy to build
• Light weight

SOLUTION:

Build blade like surfboard. Thick blade for strength and light weight. Moderately rough surface okay.

Keep gudgeons well separated to keep upper gudgeon lightly loaded.

For swim step transom, use stern pulpit to support top gudgeon.

MATERIALS AND SUPPLIERS:

Foam blank - "Lastafoam" medium density urethane foam boards available from Svendsen's in 1.5" x 4' x 8' sizes or cut fractions at $8.59 per square ft.

Epoxy: TAP Plastics 314 marine epoxy resin ($50.25/gallon) and 143 slow hardener ($33.35/half gallon). Or West System epoxy (West Marine or Svendsen's).

Glass: "Knytex" from Tap Plastics, or similar. This is a mat-cloth combination totaling 25.3 oz. per sq. yard. $12 per 36" of 50" wide material. Selvege tape lapped around leading and trailing edges. (Tech. contact at TAP: Russ Miller, manager at San Leandro, 510-357-3755.)

Rules for fiberglass/resin/foam work:

1) Always make a test patch
2) Cut glass carefully to size before mixing resin
3) Use a very good particle mask

DEPLOYMENT:

Allow full rotational degrees of freedom at lower gudgeon during deployment. Only one bolt in rudder and one bolt in transom, fitted loosely. Additional bolts added after top gudgeon is in place to establish alignment.

DESIGN METHODOLOGY:

1) ESTIMATE DESIGN SPEED

• This determines the maximum force on the rudder blade. Suggest 10 knots for 45 ft. boat, 6 knots for 30 ft. boat.

2) DETERMINE LENGTH OF THE BLADE

• Try to go to at least half the depth of the original rudder, and up to the middle or upper stern rail. (Measure depth from the transom bottom, not from the static waterline.)

3) CALCULATE FORCE ON THE BLADE:

• Use the formula:

  F = A * Cl * 1/2 * RHO * V^2

  F = force (lb)
  A = area below transom (ft^2)
  Cl = Coeff. of lift (use 3.0 to allow for pumping transients)
  RHO = density of water (1.9905 slugs/ft^3)
  V = design speed (ft/sec)
  (1 knot = 1.6878 ft/sec)

  F = 8.5 * A * V^2

  F = force (lb)
  A = area below transom (ft^2)
  V = design speed (knots)

  [example: 1 ft. x 4 ft. blade, 7 knots: F = 1,666 lb.]

4) DETERMINE BENDING MOMENT AT THE LOWER GUDGEON:

• Assume the force is centered between the lower gudgeon and the blade tip. if this distance is L, then:
  M = 1/2 * L * F

  M = bending moment (ft-lb)
  L = distance from lower gudgeon to tip (ft)
  F = maximum blade force at design speed

  [example: L = 4 ft, so M = 3,332 ft-lb)]

5) DETERMINE THE REQUIRED SECTION MODULUS:

• Use 10,000 psi as design stress in low-tech laminate.

  Required "section modulus" = M*12/10,000 (the 12 is to change moment from ft-lb to in.-lb)

  [example: SM required = 4.0 in^3

6) DETERMINE THE REQUIRED THICKNESS OF FIBERGLASS LAMINATE:

• SM = W * (T^3 - t^3) / (6 * T)
  (section inertia divided by half of max thickness)

  SM = section modulus (in.^3)
  W = width of blade (in.)
  T = overall thickness of blade (in.)
  t = thickness of core material (in.)

  [example: blade is 12" wide (but use 10" to account for shaping), core is 1.5" thick: By trial and error, use T = 2.02". SM = 4.02 in^3. So required thickness of fiberglass = 1/2 (2.02 - 1.50) = 0.26 in.]

7) CALCULATE LOAD ON UPPER GUDGEON:

• Upper gudgeon force: FU = M/D

  FU = force on upper gudgeon (lb)
  M = Bending moment at lower gudgeon (ft-lb)
  D = distance between gudgeons (ft)

  [example: For D = 6.0, FU = 3,332/6 = 555 lb]

8) CALCULATE LOAD ON LOWER GUDGEON:

• Lower gudgeon force: FL = FU + F

  F = force on blade (lb)
  FU = force on upper gudgeon (lb)

  [example: FL = 555 + 1666 = 2221 lb.]

9) SIZE PINTLES:

For pins in double shear (as in turnbuckle clevis pins) use safety factor of 5 and look in rigging catalog for appropriate turnbuckle size. Or use allowable shear stress of 6,000 psi for same result.

A = 1/2 * FP/sigma (for double shear)

sigma = allowable shear stress (use 6,000 psi for 316 stainless)
FP = force on pintle (upper or lower, lb)
A = required area of pintle pin (in.^2)

Solve for required pin diameter = sqrt(4 * A / PI)

[example: A = 1/2 * 2,221/6,000 = 0.1851 in.^2; pin diameter = 0.486 in., use 1/2 in. diameter pin for bottom pintle. For top, 1/4 in. diameter is sufficient, but use 3/8 in. for easier alignment.]

Simple, Cheap Backup Rudder

Running Rigging for Offshore Sailing

By Bruce Schwab

As you prepare for the West Marine Pacific Cup, you’ll hear this over and over: “This (fill in the blank) is really, really important, don’t skimp on the bucks on this one or you’ll be screwed.” I wish I could say it is a different situation with the ropes on your boat, but alas, it is not. On a long ocean race, problems with halyards and running rigging are among the most common of failures. Here are some suggestions:

#1: PULL THE RIG. You are nuts if you don’t, unless you’ve done it recently or want to spend a lot of time pulling yourself up and down.

#2: SWITCH TO ALL LINE HALYARDS. Wire is becoming a thing of the past. Spectra, Technora, or Vectran fiber all have about the same stretch as wire and are lighter and more flex resistant. Wire is still more economical than high tech line but I would only use it on the main and jib halyards if you need to pinch $. For a non-surfing boat plain dacron line may be ok for the spinnaker halyards but not for much else. The high tech fiber lines give the very best strength to weight ratio when the “single braid” (12-strand) style is used with dacron sleeving added where you need to hang onto it. These assemblies look pretty much like a wire/rope halyard except the wire is single braid line. The only drawback with these as halyards is that they are so light that if you let go of the end of the halyard it blows far away from the boat.

SPINNAKER GEAR: Probably the most common problems are with spinnaker halyards and afterguys. These lines take tremendous flex and wear in a downwind race. What often works for a whole season on the Bay gets wasted surprisingly fast in heavy ocean reaching and running.

MASTHEAD: The 2 most common masthead setups for spin halyards are externally hung blocks off of U-bolts, or a “Tri-sec” type where the halyards exit straight off the sheaves over chafe bars or rollers.

If you have externally hung blocks, make sure the bracket that extends them out from the masthead goes far enough to allow the blocks to swing well clear of the headstay or anything else. Also check the wear at the interface of the U-bolt and the block shackle. These often tend to saw through each other. It is becoming very popular to use spectra webbing or lashing here instead of shackles. Many wraps of spectra can be incredibly strong, light, and can flex forever. Make sure that there are no sharp metal edges touching the line.

For a tri-sec style masthead, if you had wire halyards get rid of them (more on this later). These mastheads are fine as long as the chafe bars or rollers have enough smooth surface area for the rope to bend around and spread the load out. Install new rollers if needed.

Make sure you have 2 spin halyards. It is customary to run at least one spin halyard external for these downwind races. The extra windage won’t hurt off the wind. I prefer not to run more than one external to avoid having too much line flopping around.

AFTERGUYS: The afterguys take a lot of wear at the pole tip so one thing to check is the pole ends. For boats over 35’ or so I highly recommend an offshore style pole end with a lot of bearing area for the rope. For the guy itself it is hard to beat single braid spectra for its wear and flex life. Use a heavy “donut” to keep the shackle from messing the pole end or getting stuck. On larger boats you may need an aluminum donut that won’t split under high load. Svendsens makes a high load aluminum donut that I designed for boats over 50’.

SHACKLES: For both the spin sheet and the guys use large bail shackles. These bear on the donuts better and allow enough room to hook the guy into the sheet shackle bail. Use “internal release” style shackles that can be spiked open under load and also have less of a tendency to “flog off”.

Consult with a rigger on how to properly prepare the spinnaker lines for chafe. There are now very effective urethane coatings that really help. There is also good ol beeswax and leather, which are sometimes hard to beat.

If you have a jib furler, remember to keep the spin halyards out of the way. Flip them behind the shrouds when not in use. One good “halyard wrap” and a halyard can be messed up good.

JIBSHEETS: Go for a line with a high tech core. Dacron is too stretchy for jibsheets unless you want to constantly adjust them for every puff and wave. For Bay racing jibsheet shackles are nice for tacking, but for ocean sailing knots are fine.

Quick overview of line fiber types

SPECTRA: Best flex life. Very slippery so also great for chafe. Very low stretch under oscillating loads. Problem: Under steady high loads, spectra “creeps” or gets slowly longer. Usually not the greatest for main and jib halyards.

TECHNORA: Very strong and low stretch, with little or no creep. Does not have the flex life of spectra and should be protected from the sun. Great for main and jib halyards.

VECTRAN: Also very strong and low stretch, with little or no creep. A little better flex life than technora but not near that of spectra. Great for main, jib and universal (combo jib & spin) halyards. Rather expensive.

There is a lot more to look for, but I’ll have to write a book later. Whatever you do, at least be sure to have a reputable pro check out what you are doing well before you leave!

Good Luck!

Bruce Schwab won the Singlehanded Transpac in 1996 aboard “Rumbleseat”, his highly- modified 1930 “30 Square Meter”. In 1998 he and fellow rigger Jim Plumley took first in Doublehanded Division 2 aboard the 31’ prototype sportboat “Azzura” with an elapsed time of 10 days flat. Bruce has won his division in the Doublehanded Farallones 7 or 8 times but can’t remember. In 1999 he and crew member Joakim Jonsson were awarded the Arthur B. Hansen Rescue Medal by US Sailing for the rescue of fellow racer Gary Helms in the 1999 Doublehanded Farallones Race. Mr. Helms had capsized near the Farallones Island in heavy conditions. http://www.rigworld.com

Sail Inventory Suggestions for San Francisco to Hawai’i Passage

by Synthia Petroka

What is your budget & expectations?

Minimum: Mainsail, #3, #1, .75 oz AP spinnaker

Budget: Minimum plus blast reacher (135%) or butterfly, and 1.5 oz shy kite

No limit: Budget plus jib top (155%), more kites than food!

Sport Boats: Asymmetric spinnakers

4 Legs of the race

Start to Pt. Bonita: Beat

Normal: start with #1, change to #3 outside gate

Light air: Light #1

Heavy air: #3

Close Reach: Can’t carry yet

Normal: Blast Reacher

Light air: Jib Top, Drifter, Code Alpha, VMG spinnaker

Heavy air: Blast Reacher

Running:

Normal: Reacher or shy kite, asymmetric, what you have when you can

Light air: Drifter

Heavy air: shy kite

Trade Winds to Finish:

Normal: full sized spinnaker during day-runner. At night, heavy air

kite, butterfly jib, polled out blast reacher

Light air: .5 oz, AP for higher AWA

Heavy air: shy kite

Storm Sails: storm trys’l, storm jib, Gail sail (ATN)

Spinnaker Socks: ATN

Spinnaker Nets: fills fore triangle with something to keep spinnaker from wrapping around

forestay.

Outgrabbers: floating block suspended from boom, attaches to spinnaker sheet between clew and

boat, pulls clew outboard to stabilize spinnaker.

 

Sail Repair Suggestions, by Synthia Petroka

Sail repair kit

General items

Scissors – strong enough to cut boltrope Sailmakers palm – don’t scrimp here

Sailmakers needles Waxed hand sewing thread

Seam ripper Insignia cloth repair tape

Webbing Leather

Spare battens Denatured Alcohol

Ice pick or awl

Luff attachments

Slugs, slides, shackles, round rings

 

 

Take your sails to a loft to be checked

Sail Lofts:

UK Sailmakers Alameda 510-523-3966 www.uksailmakers.com

Spinnaker Shop Palo Alto 650-858-1544 www.spinnakershop.com

Santa Cruz Sails Santa Cruz 831-454-0868

*used Sail Warehouse, The 831-646-5346 www.thesailwarehouse.com

*used Sail Exchange 949-631-0193 www.sailexchange.com

Rooster Sails Alameda 510-523-1977 www.roostersails.com

Quantum Sails Richmond 510-234-4334 www.quantumsails.com

*used Pineapple Sails Oakland 510-522-2200 www.pineapplesails.com

North Sails Alameda 510-522-5373 www.northsails.com

Neil Pryde Sails Sausalito 415-827-1177 www.neilprydesails.com

Lee Sails Alameda 510-523-9011

Larsen Sails Santa Cruz 831-476-3009 www.neilprydesails.com

Hood Sailmakers Sausalito 415-332-4104 www.hoodsailmakers.com

Hogin Sails Alameda 510-523-4388 www.hoginsails.com

Haynes Sails San Rafael 415-459-2666

Halsey Lidgard San Mateo 650-347-2540 www.halseylidgard.com

Doyle Sailmakers Alameda 510-523-9411 www.doylesails.com

Problem areas to check:

Head: Headboard, webbed rings, web loops

Luff attachments: Slugs/slides, grommets, shackles

Reefs: Pressed ring corrosion, intermediate points

Corners: Corner & sail body join

Leech: Leech line and cleats, Batten pockets

Stitching: Seams, UV covers

PREVENT Medical Emergencies

Prevent_Medical Emergencies
by John H. Wright, MD

Health and safety at sea, particularly under the stress of racing, requires planning and preparation for ultimate success. It is quite important to acquire an appropriate medical kit and know how and when to use it. It is more important to prepare so that it will not be needed; -i.e., “an ounce of prevention is worth a pound of cure.”

Know yourself and your crew-strengths, weaknesses, and special needs. It may well be advisable for all or some of the crew to visit with their doctor to explain that they will be isolated from usual medical care for a period, to obtain medication or advice concerning any ongoing health problems, and the skipper should be fully knowledgeable of these problems. A visit to your dentist may be equally useful. Certainly crew selection must consider health deficiencies. For instance, I regularly sail with an insulin-dependent diabetic crew member and our kit has insulin. The member and the skipper know when and how to use this. It might be unusually hazardous for someone who requires close, regular medical attention to be isolated for two weeks or more, and their doctors could so advise. Some illnesses are likely to become significantly worse under the stress of fatigue, seasickness, or physical demands not normally encountered. Ischemic heart disease (angina), diabetes mellitus, seizure disorders (epilepsy), many psychological disorders, drug or alcohol dependence, peptic ulcer disease, migraine (headaches), irritable colon problems, and even rheumatoid arthritis are only a few which are recognized to be frequently worse with stress. Perhaps, in a specific instance, none of these would disqualify a known and valuable crewmember, but medical advice is needed and planning for special care or medication required. Certainly ideal low risk crew health would be important to consider in crew selection.

Frequently, little attention is given to crew physical conditioning. We hear of some conditioning by Olympic sailors or by dinghy sailors or 12-meter contenders but seldom by others. Again, serious consideration to physical conditions should be given. A strong crew person with good cardiovascular reserve and stamina is much less likely to be injured or become ill. If possible, a regular exercise program with aerobics for two or three month’s pre-race would pay dividends in safety, enjoyment and performance. An additional benefit might be some weight loss (who needs a heavy crew for a long, downwind ride).

This brings up diet (pre-race). I have seen some articles in sailing magazines recommending training diets. I am not saying these might not be useful, but I would be satisfied for my crew to be on an established, usual, nutritionally sound diet (weight reduction if overweight), with great attention to adequate fiber intake for regularity and a reduction to a minimum in alcohol or other drug use for two weeks prior to the race. Vitamin supplements should be considered before and during the race.

Prevention of seasickness also begins prior to sailing with diet and avoidance of alcohol or much caffeine, spices, or fatty or heavy foods prior to departure. The use of anti-motion sickness drugs should be considered. The most effective items are prescriptions and must be obtained from a doctor. I like Transderm Scopolamine patches, but some in my crew prefer oral medication. We have had reasonable success with Phenergan and ephedrine in individual doses. I caution that these should only be used if tried previously, as the best anti-motion sickness medications all have some undesirable side effects – often sleepiness or dizziness.

Some instances of drug interaction with other medications exist and require individual doctor’s advice. Much of the prevention of seasickness lies with good physical conditioning and proper diet. Lack of fatigue, adequate warmth, how one is positioned on the boat, visual clues, lack of head motion and each individual’s means of dealing with unaccustomed visual clues versus vestibular clues (balance, acceleration, gravity) affects one’s responses. Most of us with any ocean time are familiar with this. We also know how handicapped one may be if significant “mal de mer” occurs. Again, this factor should be addressed in crew selection; however be aware that if serious seasickness does occur, the crew member will need care and on rare occasions, could become so dehydrated from vomiting and the inability to retain oral fluids that medical/hospital care for intravenous fluids may be required.

In consideration of health, maintenance and the prevention of problems, it is not often recognized, except in aviation circles, that smoking results in significantly poor night vision as well as all the other known effects on the lungs, throat, and heart and blood vessels.

At least two crewmembers should have knowledge of at least basic First Aid. Red Cross courses are not expensive, are readily available, and are useful. If possible, a course in CPR (cardiopulmonary resuscitation) should be obtained for two crewmembers. Of course, should you have a doctor or nurse as crew you would benefit.

If you are well prepared with knowledge, plans, good physical condition, and select crew, you may never even have to use your first aid kit. If you do, it will most likely be needed for common injuries.

One of the most common and preventable is a burn. “Sunburn” or ultraviolet injury, totally preventable, is best treated by absolute limitation of any more exposure, increased fluid intake, aspirin or Tylenol, and skin cleansing, particularly blistered. Thermal burns from hot liquids could be serious and, if a large area of skin is involved, could result in shock, later infection, or even death. The seriousness of a burn is related to both the area involved and the depth of tissue involved-i.e. first, second, or third degree. If the throat or lungs are involved, it can be a serious emergency. All except the most superficial and small area burns may disable a crewmember due to pain, shock, or infection.

Cuts (or lacerations) are also common. Most occur on the hands and face or scalp, and all may have worrisome bleeding which can be stopped best by direct pressure applied to the wound with fingers and a bandage. Usually a large bandage will maintain enough pressure if property placed. If the laceration gapes, some physicians might use adhesive “Steri-Strips” to bring the edges together. The main principles of wound care are: 1) do no more harm; 2) clean the wound, and remove foreign matter and dead tissue; 3) bring the edges together; 4) protect with a sterile dressing (wet dressing is no longer sterile or protection). Antibiotic ointment is sometimes used but is no substitute for the above principles. The best method of wound cleaning is gentle washing with an antiseptic soap such as Betadine or Hibiclens.

Fracture of the ribs, fingers, or forearm bones could occur with a fall or with a runaway winch. Fractures of the thighbone (femur) or the leg (tibia) are common on the ski slope but unusual on sailboats. Penetration of skin by bone ends or a laceration over the bone results in a “compound” injury, which is more severe because of infection danger. All fractures (except a single finger) are likely to disable a crewman for the duration. All must be treated by placing the affected part at rest (splitting) with adequate padding (swelling will occur) and any available material to keep broken bones from moving. I have used a rolled magazine or large cushion with battens or commercial splint. Fingers may be taped to other fingers or taped to a cloth (bandage) roll in the fist. Sprains (torn ligaments) and strains (muscle injuries) may also be treated with splitting. Larger bone fractures could cause a lot of blood loss into the surrounding tissue and, with pain, result in shock.

Shock is a condition characterized by falling blood pressure: symptoms include cold, moist skin; rapid, weak pulse; nausea; thirst; fear or even loss of consciousness. It may accompany many injuries especially particularly severe, extensive burns; considerable bleeding; severe infections (sepsis); prolonged vomiting or diarrhea; heat prostration; or hypothermia. Usual treatment of shock is aimed at increasing intravascular volume so that more blood will be returned to the heart, allowing an increased stroke volume and output, thereby increasing blood pressure and circulation; hence, the administration of IV fluids is a standard treatment. On a racing yacht, this may be impractical unless trained people and adequate equipment are carried; however, blood return to the heart can be improved by first aid means. Have the victim lie down with legs elevated; keep him warm; splint fractures; dress burns; stop bleeding; and, when he is able, give him liquids containing calories and salt such as broth, and ease pain with medicine. The presence of shock usually means a serious illness or injury that will require medical advice and likely more care than available aboard.

A head injury may result from a fall or a blow by an object such as the spars or winch handle and unconsciousness is quite serious if it occurs more than briefly. Scalp lacerations may be very bloody and can lead to shock. Serious head injuries with brain tearing or bleeding inside the skull are often fatal, even with prompt, expert care; however, basic first aid should be begun in all cases. Treatment is similar to that of shock but the victim is best placed on one side or prone since vomiting is common.

Breathing may be compromised by relaxation of the jaw and tongue, and airway maintenance is vital. Unconsciousness may be accompanied by seizure or unconsciousness may follow a seizure for some minutes. Medical help is necessary for any episode of unconsciousness beyond a very few minutes.
A multitude of minor, but in the circumstances important and disabling, illnesses might strike. Most require little more than symptomatic care but could disrupt the crew duty assignments. One could foresee flu, colds, sore throats, minor intestinal upsets, toothaches, urinary tract infections, minor vaginal infections in the female crew members, or (as has in the past occurred) drug or alcohol withdrawal or toxicity or psychiatric illness (psychosis). Some of the latter can be quite seriously disruptive and hard to deal with.

As a rule, significant medical illnesses such as hepatitis, pneumonia, heart attack, and stroke are unlikely if crew selection is good but if these occur would require medical help. I have often been concerned in a young group about appendicitis with its characteristic abdominal pain and vomiting but this seems to be very rare in the racing or cruising groups. Again, medical help by radio and rapid evacuation of the ill person may prove necessary. The characteristic pain and tenderness localized finally to the right lower area of the abdomen is the usual indicator for suspecting this diagnosis.

A crewmember overboard, particularly in the cold, coastal North Pacific (even if recovery is prompt) may experience hypothermia. This condition, a result of heat loss and a fall in body temperature, may be recognized by the victim’s confusion, blue lips, shivering, and muscular incoordination. Shock or heart beat (pulse) irregularities may occur and CPR training may come to use. The symptoms may be somewhat delayed at the onset. Any person overboard in cold water should be suspect. Treatment consists of warming, drying, and resting the patient. The skin should only be heated by placing the person in a sleeping bag or blankets and another person may supply heat by joining the patient in the bag (body contact). Avoid alcoholic beverages but when the patient is alert and not sick, warm liquids may be given. Seasickness is not an unusual accompanying complication.

In summary, many problems that could require treatment or even patient evacuation, can be prevented by crew selection, physical (doctor’s) evaluation, and conditioning. Safe practices and proper equipment can prevent many injuries. Planning and preparation can boost confidence and allow appropriate treatment of many conditions. A proper kit and the training to use it are indicated. A first aid course (Red Cross) and CPR training for two members is advised.

Hypothermia

Cold Water Immersion/Hypothermia - Survival and Rescue
Kent Benedict, MD, FACEP
"For this relief much thanks; 'tis bitter cold,
and I am sick at heart." - William Shakespeare, Hamlet, Act 1
The challenge of sailing small vessels is simply this: to get us from one point to another over the
water without adding to the discomfort or potential disaster by actually putting us into the water.
Especially cold water. This is not to say that swimming, kayaking, diving, surfing and all the other fun
things one can do in the water should be avoided, but for our simple goal of getting our boat from here
to there, staying warm and dry are our paramount concerns.(*see sidebar on being swept overboard)
Which brings us to the point of this article.
Immersion hypothermia is the medical term for one of the bad consequences of falling into cold
water. Obviously, drowning or near-drowning is the other consequence. The definition of cold water is
variable but the significant risk of immersion hypothermia is in water 77 degrees Fahrenheit or colder.
Just looking at the temperatures of the San Francisco Bay shows us that in our area the risk is universal
all year long.
San Francisco Bay Average Water Temperature(Degrees Fahrenheit)
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
52 52 54 54 54 54 56 56 54 54 52 52
It is estimated that half of all so-called 'drowning' victims actually die from the fatal effects of
cold water. Cold water robs the body of heat 25-30 times faster than air. When you lose enough body
heat to make your temperature subnormal, you become hypothermic.(*see sidebar on signs and
symptoms of hypothermia)
So what actually happens when you fall overboard into 50 degree water? When the water first
hits you, it's cold but not paralyzing. If you're wearing a PFD, and you survive the first few minutes in
the water, there's a good chance of surviving up to four hours. But it can be extremely variable,
depending on sea state, your physique, your conditioning, your clothing, and ultimately your behavior in
the water. But the first minutes in the water are critical. The moment you go in there is a gasp reflex,
causing an involuntary mouth opening and deep inhalation. If you are actually under water when that
gasp occurs one of two things will happen: in 10% of us the larynx goes into spasm and nothing can
enter the lungs, and suffocation may occur. In the rest of us there is an almost immediate flooding of the
lungs and drowning begins. Loss of consciousness rapidly follows and soon death. As Sebastion Jungar
2
wrote in his book The Perfect Storm, The panic of a drowning person is mixed with an odd incredulity
that this is really happening. Having never done it before, the body - and the mind - do not know how to
die gracefully. The process is filled with desperation and awkwardness. "So this is drowning," a
drowning person might think. "So this is how my life finally ends." If the gasp reflex were not bad
enough, there is yet another reflex which for some can be even worse — cold water causes a precipitous
rise in blood pressure and heart rate. In some, this creates such a strain on the heart that it literally stops
pumping blood. Unconsciousness and death occur almost instantly. For those who have had the good
fortune of surviving those first minutes without immediately drowning or having a cardiac arrest, they
now face the challenge of staying alive long enough for rescue. But the cold water is making it more and
more difficult. Blood is rapidly shunted away from the surface of the body in order to protect vital
organs such as the kidneys, liver, brain, and heart. Uncontrollable shivering begins. Muscle coordination
and strength wane. Studies have shown that after the first five minutes in 50 degree F water, muscle
strength decreases by 1.8% per minute.(*see sidebar on muscle fatigue). Disorientation and confusion
begin. It becomes harder and harder to think straight. The hands are now numb and unable to grip. The
legs are so weak that any attempt to swim or even tread water is useless. And even if the sea is
moderately calm and the PFD is maintaining the head above water, the constant splashing of small
waves makes it impossible to keep water out of the nose and mouth. If rescue does not happen soon,
death is inevitable.(*see sidebar on the Titanic)
Okay, now that I've painted such a fatalistic picture, let me try to get you out of this mess.
Fortunately, the whole issue of cold water immersion has been extensively studied and from those
studies we can give reasonably good advice based on solid evidence. But first of all, it is important to
understand that there is at least one factor which you have little control over — your physique. Children
are especially prone to hypothermia because of their high skin surface to body mass ratio. And for the
same reason, tall skinny people are far more susceptible to hypothermia than short, fat, or highly
muscular types. As an example, in July 1993 in the Straight of Georgia, Canada, a man fell off a ferry
into 61 degree F water. He had no PFD. The predicted survival time in that water is around five hours.
But he drifted overnight, over 8 hours, and was rescued in the morning. He was found to be only
moderately hypothermic. And although the media heralded this event as a 'miracle', it could better be
described as not that unusual - the man was a well muscled 6'4", 220-pounder. His bulk of muscle and
fat made him a slow cooler, and he survived.
But what factors can you control if you do happen to fall into cold water? Above all, don't panic!
Panicking exhausts your reserve energy and strength. There is a physiologic reflex to hyperventilate in
cold water. Try to consciously slow your breathing. Hyperventilation can quickly produce muscle
cramping and spasms.
And then try to remember the following:
• Keep wearing all your clothing. Do not remove anything unless possibly your seaboots if they
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are weighing you down and pulling you under.
• Button, buckle, zip and tighten collars, cuffs, shoes and hoods. Do this quickly, before your
hands are numb and muscle strength is gone. Cover your head if possible. A layer of water trapped
inside your clothing will be slightly warmed by your body and will help insulate you from the colder
water, thereby slowing body heat loss.
• If you were not wearing a PFD when entering the water, there is a chance an alert crew has
tossed one overboard. Find it and put it on immediately.
• Look for a nearby rescue line or float and swim to it if at all possible.
• At this point devote all your efforts to getting out of the water and continue to act quickly
before you lose full use of
your hands and limbs. Climb onto anything floating. The object is to get as much of yourself out of the
water as possible. Even though you are now exposed to wind and spray, you will not lose heat as rapidly
as you would in the water. "Wind-chill" is not anywhere near as lethal as staying in the water.
• Do not attempt any further swimming unless it is absolutely necessary to reach a nearby boat or
another person. Unnecessary swimming "pumps" out warmed water between your body and your
clothing causing new cold water to take its place. Excessive movement of your arms and legs can reduce
your survival time by as much as 50%.(*see sidebar on Dancing Ledge)
• If there is no floating object nearby to hold onto, then assume the Heat Escape Lessening
Position (H.E.L.P) by holding knees to chest. Wrap arms around legs and clasp hands together.
• If there are others in the water, huddling together can extend survival time up to 50%.
• Continue remaining as still as possible. It may be painful but remember that intense shivering
and severe pain are natural body
reflexes in cold water which will not kill you. Heat loss will.
For those of you who are still on-board and are now going to be assisting in the rescue, I offer
the following advice:
• The first principle of rescue is to get the victim out of the water as soon as possible.
Immediately throw into the water anything that the person might be able to wear or hang onto. Make
sure that at least one crew watches the victim at all times. Get the boat back to the person using
whatever technique you have practiced in your man-overboard drills.
• After the first 5-10 minutes do not expect the victim to able to get out of the water unassisted.
After 15 minutes, assume the victim is already significantly hypothermic and will be helpless to assist in
his own rescue.
• Remove the victim from the water gently and in a horizontal position. Even mildly
hypothermic victims, if forced into a vertical or standing position, can suddenly drop their blood
pressure and lapse into unconsciousness.(*see sidebar on post-rescue dangers)
• Gentle handling of the victim is extremely important since excessive jostling can produce lethal
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heart arrhythmias in the moderately hypothermic person.
• If the victim is unconscious, not breathing, and no pulse, then CPR is indicated. But, before you
start CPR you must make absolutely sure that there is neither pulse nor breath. In severely hypothermic
victims, respirations and pulse may be slow, shallow, and difficult to detect. Therefore, take at least a
minute in assessment before commencing with CPR.
• You may have to continue CPR for a long time. A few years ago, a severely hypothermic 25
year old woman was rescued in the Sierras. During transport she suffered a cardiopulmonary arrest but
was successfully resuscitated after 3 hours of CPR.
After recovery from the water and initial management of any life-threatening emergencies the
objective is the prevention of further heat loss.
• Minimize physical activity. The physiologic process known as "afterdrop" produces further
cooling of the body long after removal from the water. This can be aggravated by physical activity
where the cool body surface blood is suddenly mixed with the warmer core blood. Experiments on
moderately hypothermic volunteers have demonstrated a threefold greater afterdrop during treadmill
walking than when lying still.
• Remove wet clothing, gently dry the skin, and then wrap the victim in a dry insulated blanket,
rescue bag, or sleeping bag. If further heating of the victim is warranted, then the safest method is
"buddy warming" where a crew member joins the victim in the blanket or sleeping bag. The buddy
should concentrate on lateral chest to lateral chest contact. Lower extremity contact is unnecessary so
pants don't have to be removed.
• Avoid using heating pads or hot water bottles because of the high risk of further skin damage.
Hypothermic skin is injured skin and there have been cases of third degree burns resulting from their
use. If it is felt the devices must be used it is mandatory that they not be in direct contact with skin. Use
clothing or blankets as a barrier.
• Do not give hot food or liquids unless the victim is fully alert and awake. There is a strong
vomiting reflex in hypothermia. The drinks and food may help the morale of the victim but are only
minimally effective in raising the temperature.
• No alcoholic drinks, cigarettes, or coffee in any hypothermia situation.
Ultimately, any person who has suffered anything more than a very minimal cold water
immersion should be brought to medical attention as soon as possible. There are many case histories of
death occurring hours after the incident.
Signs and symptoms of hypothermia
• Minimal/moderate hypothermia: Body temperature has dropped below 96-97º F, but is
still above 90º F. The victim feels cold, is quiet and reluctant to communicate, shivering is prominent.
• Moderate/severe hypothermia: Body temperature now is between 90º F and 85-86º F.
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Victim is semiconscious, movement is slow and uncoordinated, muscle rigidity has set in and shivering
stops.
• Severe hypothermia: Body temperature is below 86º F and the victim is unconscious,
pupils are dilated, there is depressed breathing, and a high likelihood heart arrhythmias. The victim often
appears dead.
• The 3 best rapid clinical signs to determine degree of hypothermia are 1) Skin
temperature of the back: if warm, then hypothermia is usually not present. 2) Shivering: Starts when
body temperature drops below 95º F, stops somewhere around 90º F. 3) Mental status markedly
deteriorates below 90º F.
On being swept overboard
"The most dangerous position is on the foredeck, shifting jibs or setting or lowering spinnakers (but)
where most accidents take place is in the comparatively safe position of the cockpit, when safety belts
are temporarily detached when changing helmsmen, or when a man emerges from below to empty a
gash bucket, to be sick or to come on watch." - K. Adlard Coles Heavy Weather Sailing
I would also add to Coles' thoughts — taking a piss over the side of the boat can be a high risk
proposition. Often when the dead body is recovered, the pants are found with the fly open.
The story of Dancing Ledge
On Sunday, the 29th of July 1956, in a Force 11 storm(winds 56-63 knots), the 10 ton cruising yacht,
Dancing Ledge, foundered in the English Channel only a mile from land taking three of her crew to their
deaths. The sole survivor of the tragic event, Mrs. O'Sullivan, wrote — "We were pooped almost
immediately. Water broke through the starboard cabin top combing, which burst inwards. Two or more
seas heaping together spilled a few more tons of water on top of us, and Dancing Ledge went down very
quickly. I was in the cabin, which seemed to fill from every direction...We hit the bottom or something
hard...In the cabin full of water, and dark, I got free by wriggling my feet out of my shoes and groped
out...The life jacket took charge once I got into the cockpit, and I went up fast for a long, long way."
Mrs. O'Sullivan, Colonel H. Barry O'Sullivan(her husband), and one other crew(the fourth crew had
apparently already died) soon found the vessel's upside-down dingy floating nearby. The trio clung to
the dingy over four hours before a rescue vessel appeared. According to Mrs. O'Sullivan, "Barry insisted
we should 'bicycle' continuously with our legs in order to keep warm and to avoid stomach cramp..." A
British navy frigate, H.M.S. Keppel, approached at about this time. Colonel O'Sullivan took off his
orange jacket to wave it above the spray to attract attention. With extreme difficulty the frigate was
maneuvered alongside and a rope was thrown to Mrs. O'Sullivan. She let go of the dingy with one hand
to grip the rope. Her hand was so cold and rigid that she could not close it around the rope. She let go of
6
the dingy with the other hand to attempt to get a stronger grip, but it was impossible to hold the rope and
it ran through her hands as a wave, deflected by the bulk of the frigate, swept her along the length of the
ship and she drifted away into the clear. Now supported only by her life-jacket, she became
unconscious. Within a few minutes the ship sent a rescue swimmer, secured by a lifeline, into the water
where he was able to bring the comatose woman back to the ship and carry her up the scrambling nets.
Once she was aboard, the search for the others continued, but the ship could find no trace of them or the
dingy.
The Titanic
At approximately 11:40 PM on April 14, 1912, the Titanic struck the iceberg and the ship sank in calm
seas. The water temperature was near 32 degrees F. Of the 2201 people on-board, only 712 were
rescued. A rescue vessel had arrived with two hours of the sinking, yet 1489 people died in the water.
Nearly all were wearing 'life preservers'. Although the official cause of death was listed as 'drowning',
the most probable cause was immersion hypothermia.
On the dangers of the post-rescue period
"I was the last man to be picked up. Everyone was conscious when taken out of the water but many of
the men lost consciousness when taken onto the warmth of the trawlers. Nine of the men died on board
soon after being picked up. We were all given a small mouthful of spirits... and this made us sleep, and
these unfortunate men went to sleep and did not wake up again" — Captain H.J.M. Downie of the SS
Empire Howard which sank in 29 degree F water in the Arctic Ocean
On muscle fatigue
"I was pulled out of the water into the boat.... I had by this time been in the water about 2 1/2 hours, the
temperature of which was 47 degrees F, and my body was completely numb when rescued" — Captain
F.D. Straus of the SS Manchester Merchant in the North Atlantic
Dr. Benedict is a board-certified emergency physician and USCG Licensed Master. From 1980 to 2002
he was the Chief Medical Officer for the California Maritime Academy's training ship, USTS GOLDEN
BEAR. He holds the appointment of Clinical Associate Professor of Medicine at Stanford. He has taught
Emergency-Medicine-at-Sea courses for years, written articles for Latitude 38 and authored the medical
chapters in the standard US Maritime texts the American Merchant Seaman’s Manual and the Merchant
Marine Officers’ Handbook. He cruised extensively on his own vessel, the San Juan. Currently he is the
Medical Director of Emergency Medical Services in Santa Cruz and San Benito Counties. In his spare
time he is a Caribbean charter captain.
For further information or consultations call (831) 662-0668 or e-mail skylax@cruzio.com

Pacific Cup Insurance from Old United

Pacific Cup Yacht Race Insurance

Thanks to the efforts of PCYC's special operative at Polaris Insurance, Old United Casualty Company and Polaris Risk Management have joined together to offer an endorsement for Pacific Cup race insurance.  For more information and to request a quote, please contact:

Pat Lowther

 plowther@polaris-ins.com

925-677-7400 x2012

To learn more about the Old United policy go to:
The Millennium Mariner Gold Product Description Page:
http://www.oldunited.com/productsMillennium.aspx

 

Go to the bottom of the page and click on the Quote Form link; and then scroll down to
“Optional Coverages”, where you will see “[   ] Pacific Cup Race Endorsement” . 

Be sure and check this box!

To go directly to the quote page:
 

The Millennium Mariner Gold Quote Submission Form Page;
http://www.oldunited.com/productsMillQuote.aspx
 

Scroll down to “Optional Coverages”, where you will see “ [   ] Pacific Cup Race Endorsement” .  Be sure and check this box!