Systems

Note we do not have any financial arrangements or other interests in any the products mentioned here!

For just about every question, there are almost as many different opinions as there are sailors. And, most of these different opinions are in fact valid for the specific individual with their particular boat and their unique mission.  That said, below are our opinions based on our experiences to date.  We reserve the right to change them, or even admit they are wrong, at any later date :)


8. What sort of anchor do you use?

8a. What sort of snubber setup do you use?

11. Do you carry guns?

13. How do you manage without a refrigerator/freezer, especially in the tropics?

16. How much fuel do you carry and use?

19. How do you keep warm in very cold places?

20. Do you have a watermaker?

21. Do you use your windvane much?

23. What lessons can be learned from new cruisers starting out down the west coast?

24. What sailing programs do you really use on your computer?

26. How much fuel, water and electricity do you use?

27. What dinghy do you use/recommend?

29. What sort of batteries & battery bank do you have?

35. What do you do about lightning?

36. What do you use for electricity generation?

39. What sort of navigation equipment do you recommend and which equipment should be visible from the helm?

56. How should we evaluate our battery & charging requirements?

57. How should we evaluate of heating & hull insulation requirements?

60. What should I do to make sure we don't get water in our engine?

63. With your anchor testing, why did you test a 2:1 scope and do the results apply to smaller anchors?

68. After 11 years, is there anything you would change in your 'left off the boat list'?

69. What sort of work do you need on Hawk after 11 years hard cruising?

74. Should we install a radar reflector?

78. What have you done regarding LED navigation lights?

86. What are your thoughts on emergency bilge/dewatering pumps?

87. How do you light your diesel heater?


Also see:

What we left off Hawk - 2000, Blue Water Sailing

Simple boat Systems - 2000, SAIL


8. What sort of anchor do you use?

First, we like BIG anchors.  This photo shows why.  Big anchors are your best insurance and let you sleep soundly.

On Hawk, we carry one main anchor on the bow, which for most of our time aboard has been a 110lb Bruce.  On Silk, we carried a 44lb Bruce.  We have had flawless performance with both these anchors, despite the fact that the Bruce always seems to do poorly in the anchor tests (which I think indicates a serious weakness in the anchor testing methodologies). On Hawk, we carry three other anchors stowed below: a 55lb Delta, a 40lb Danforth (actually a West Marine Hi-Tensile version of the Danforth) and an FX-55 Fortress.  90% of the time we anchor with only the Bruce.  We have occasionally used the Danforth as a kedge, to hold us off a nasty dock, or to hold the bow into the swell in a rolly anchorage.  The other two anchors we have only used once in Hurricane Lenny.  We feel strongly that cruisers are much better off carrying one slightly larger anchor on the bow rather than two 'normal-sized' ones.  This is a straight forward win-win as the one slightly larger anchor will give you better everyday holding and sailing performance is also improved by reducing weight on the bow.  On the very rare occasions when we have needed a second anchor, there has always been plenty of time to get it out of the lazarette.

In November 2007, we sent our Bruce off to be regalvanized, as we have about every 5 years. It came back with serious cracks around the shank right where it joins the blade.  I can only guess that they heated it too fast or cooled it to fast, as very little else could break a 110lb genuine Bruce. We had a welder look at it and he pronounced it unfixable.  So, since the Bruce is no longer made, we are evaluating the available anchor options and have spent the last few months cruising with a copy of one of the 'roll-bar' anchors.  We have carried a 55lb Delta for 9 years as a 'spare' main anchor, but when it came to actually needing it I realized that while I would be perfectly fine using it as a main anchor in most places around the world, I am not comfortable with it in Chile and S. Georgia.   My lesson learned is that if I am going to the effort to carry a 'spare' main anchor it needs to actually be as big and capable as the main anchor. So, I will probably be replacing it also, hopefully with something that stows more compactly than the roll-bar anchors.

(Feb 9th 2008) We now have 3 months experience cruising Chile with a copy of one of the 'next generation Roll Bar' anchors.  Our conclusion is that it is excellent in sand & mud bottoms where it can bury but that it is not as good as the Bruce in rock and coral bottoms (full report here).  After testing 50kg Manson Ray, Supreme and ROCNA anchors (report here), we conclude that we still like the Bruce design (the Ray is a Bruce copy) as it consistently sets in a wider range of conditions than the other designs. Our thinking is that if an anchor does not consistently set (or reset in a wind shift), then it does not matter what it's theoretical holding power is.

We are using 3/8" G4 (high test) chain.  My understanding is that the heat involved in the regalvanazing process destroys the high test heat treatment, so after regalvanizing our chain twice (we need to do it about every 5 years), it is now probably just regular strength chain.  We carry two 150' lengths of this chain. We do this for three reasons: (1) It normally keeps the extra weight of 150' of chain out of the bow, as we find 150' of chain to be enough almost everywhere except the Pacific (it has 200' of 3/4" line on it). (2) In hurricane conditions it gives me two good pieces of chain to set two good anchors. (3) It gives me a 'spare' piece of chain in case I have to dump the primary rode sometime. Very occasionally we add the extra 150' to the main rode, for 300' of chain, in places with extra deep coral anchorages (e.g. French Polynesia) or where we need to med-moor or stern tie (the Med or Chile). Otherwise the extra 150' is stored lashed in the bilge .  When we join the two sections of chain, we use a 'connecting link', backed up with a Spectra cord lashing (which is stronger than the chain).  This connection runs smoothly through the windlass.

As anchorages have gotten more crowded, 3:1 scope has become the standard and accepted anchoring scope among the cruising fleet.  Main anchors need to be sized on the assumption they will be used with 3:1 scope, which typically means a bit bigger than the manufacturer's recommendations.

Regarding anchoring etiquette -  the first fundamental principle is that those who anchor first can ask those who anchor later to move if they have anchored too close for safety. However, it has been proven in the tight Caribbean and Mediterranean harbors that anchored boats can be packed in amazingly closely and they will swing together with no contact (assuming they are all using all/mostly chain rode and 3:1 scope) . So, the normal rule among the fleet is 'no harm, no foul' - that is you only ask someone to move if they swing so close you can touch them. If you do really believe someone has anchored too close, ask them pleasantly and politely to move. Don't yell - if you have to raise your voice they are probably in fact not too close. If someone asks you to move, do so immediately with a smile and a wave, even if you think they are wrong and an idiot. We have been asked to move three times, twice when (IMHO) we well clear of the other boat and could not possibly touch them, and the third time when the other boat had quite excessive scope out (they had 10:1 out) but in all cases we moved with a wave and a smile.  In these situations, independent of the fundamental principle 'first in', I always figure we are better off moving away from someone who does not share our understanding of anchoring dynamics/norms.

The second fundamental principle is that cruisers help each other. One aspect of this is if you see another boat dragging, you should dinghy over and make sure the crew is aware of it and offer to help them.   If there is no one on board the general rule is to let it drag and hope the crew will arrive if and only if it will not get into any trouble in the meantime. However, if it is getting into trouble - dragging down on other vessels, toward shore, or out to sea - there is an obligation to stabilize the situation. Just watching the boat drag into other boats or ashore is simply not acceptable.  It's best to stabilize the boat in the simplest, quickest, and least invasive fashion - setting your spare anchor by dinghy upwind of the boat and tying the boat to that is usually the best approach.  Other options are to tie them alongside or behind your boat, or or take their spare anchor and set it by dinghy if it is ready to go on their bow, or go aboard and let out more rode on their main anchor.  Our experience is that individual boats are very idiosyncratic and that trying to start the other boat's motor and/or pulling up and resetting their main anchor should be a last resort. Note: It is actually an international maritime law that ships masters are required to provide assistance to other ships in trouble.

Getting slightly off topic, I was shocked when a singlehander called a VHF Mayday about 20 miles from La Paz (Baja) and not one of the 400-odd cruising boats around La Paz offer assistance (we were hauled-out on the hard). If I ever have to issue a Mayday I would certainly hope for a different response than that.  The only acceptable response was for every boat afloat to offer assistance and for the net controller to then pick the three closest, fastest and biggest boats to go assist. Top of Page

8a. What sort of snubber setup do you use?

We normally use a chain hook with 30' of 10mm (3/8") nylon climbing line. We normally put out enough snubber line so the chain hook is just in the water which leaves lots of snubber line on deck to be eased out if the anchorage gets bouncy. We make sure there is a big loop of chain (say 4') hanging from the hook. The hook will then never fall off the chain. We actually like that the hooks come off easily, in case we need to move quickly or we want to put out more chain. We start taking up chain and when the chain goes tight and the weight is off the snubber, we jiggle the snubber line and the hook will come off. This is easier and faster than the 'more secure' alternative of tying the snubber directly to the chain with a rolling hitch.

We have tried several methods of attaching the chain hook to the line. Currently we have a spectra loop (10mm single braid) through the chain hook eye, and the line is tied to that with a sheet bend.  The chain hooks we get have a sharp ridge (where they split the sand casting I would guess) around the eye. That will chafe/cut the nylon line if you tie it directly (been there, done that, lost a nice stainless chain hook as a result). The spectra does not chafe (or at least it will take decades to chafe through). I had a bit of Spectra spare from an old checkstay when I was making up the chain hook so it cost me nothing, but even buying it new, two feet of the stuff would probably cost $6.  With a stainless chain hook, you could grind/file/sand the eye smooth and then tie the snubber line directly to the hook.  With a galvanized hook you would have to get it regalvanized after the grinding.  In either case the Spectra loop seems an easier answer.

We do carry two chain hooks, both in case we lose one and because you can use two snubbers with long lines to the sheet winches to pull up the chain and anchor if the windlass breaks.

We also carry an ABI snubber plate for a 'storm' snubber but have only used it a few times, once in Hurricane Lenny.  During the hurricane, we had both snubbers deployed and our normal snubber chafed through.  Having the backup snubber already in place prevented us from falling back on the chain and damaging the windlass or (since we were tied stern-to the magroves) hitting bottom with our rudder.

A long piece of fire hose over the snubber provides chafe protection. This works fine except in really extreme conditions, when we put on a backup snubber (or the ABI). 

UPDATE: I started using a new snubber system, witch replaces the chain hook with a spectra soft shackle.  It's describes in this snubber article

soft shackle snubber

 Top of Page

11. Do you carry guns?

No. There are enormous administrative hassles associated with clearing guns into and out of foreign countries.  In many countries Customs will take the guns away and only return them when you leave, which pretty much eliminates any conceivable benefit to carrying them. The one exception is in polar bear country where a long gun (shotgun or rifle) is widely recommended as standard equipment when exploring ashore in remote places. However, you still have to deal with the administrative hassles in the countries you stop at on the way to and from polar bear country.  Top of Page

13. How do you manage without a refrigerator/freezer, especially in the tropics?

When considering whether or not to install refrigeration, carefully consider the following two points:

(1) Installing a refrigerator/freezer completely changes a boat's power generation requirements.  Without one you can easily get by with a single solar panel, but with one you need to vastly upgrade your whole power generating and storage system and probably run a gen-set or motor several hours/day.  We would rather take some minor inconveniences and keep our systems simple rather than have to maintain a vastly bigger power plant. 

(2) The western 'refrigerated supply chain' for food is mostly unnecessary.  Fresh eggs will keep for months perfectly well unrefrigerated, and most fruits and vegetables will keep for ten days or more.  There are numerous tricks to maximize the length of time food will keep, which Beth covers in detail in her Voyager's Handbook.  We had fresh food up to the last day of our 59 day passage from Cape Horn to Fremantle.  Beth cans (with glass jars in a pressure cooker) meat, which preserves the contents indefinitely. She also cans homemade soups, chili, stews, etc., without extra salt and other preservatives and artificial colors/flavors, which is much tastier & healthier than store bought stuff.  Top of Page

16. How much fuel do you carry and use?

It is easy to build big tanks into a metal boat, so on Hawk we carry 200 gallons in integral fuel tanks.  On Silk we carried 75 gallons.  Both of these tankages are much bigger than absolutely necessary. As a long-term average we use about .75 gal/day. On passage we budget 1 gal/day for the expected length of the trip plus 10gal as a reserve to maneuver around the destination harbor, and the remaining fuel is a luxury which we can 'spend' 1/3 during the first half of the passage to find wind and avoid storms, 1/3 during the second half, and 1/3 for emergency usage.  Our fuel usage is integrally tied to our electrical system/no refrigeration strategy - many boats run the engine an hour or two per day in the tropics to keep the fridge cool and the batteries topped up. Top of Page

19. How do you keep warm in very cold places?

There are three areas to pay attention to.  First is clothing.  We layer polypro underwear, under 'normal wear' mid-layers, under foul weather gear.  Beth wears normal foul weather gear, but Evans often wears a Musto breathable dry-suit - in case he has to take stern lines ashore in the dinghy.  Good hats, gloves and boots are essential.  We have found all sorts of well designed hats. Evans likes a Vermont wool & sheepskin hunting hat and Beth likes skiing fleece caps. We have not yet found a perfect solution for waterproof and warm gloves.  The Goretex models we have tried all leak.  The best we have found are rubber gloves used by offshore fisherman (they look like extra big and heavy duty kitchen washing-up gloves) which have a thin fleece lining.  Cold weather boots need thicker soles than the normal yachting boot. Evans has a pair of Dunlop Purofort boots he bought in the Faeroe Islands that are perfect for him, and the standard boot among the Southern Ocean harter professionals. Beth found most marine/fishing boots to be too small/tight in the calves, and has only recently found the perfect boot for her. The Muck Boot sells commercial grade work boots at prices much less than sailing boots.  She has the 'Chore boot - mid-height', but the "muck master" would be great for those wanting a taller boot.

Second is a good cabin heater.  We use a Refleks, which is a Danish drip diesel heater designed for the North Sea fishing boats.  It's the heater of choice for all the charter boats in Chile and is extremely reliable and clean burning. We also have a 'bus heater' that runs a radiator off the engine cooling water.  It was inexpensive, has proven completely reliable and produces free dry heat when we are motoring, so the boat is always warm and dry when we drop anchor if we have motored into the harbor.

Finally, insulation for the boat is useful both to hold the heat and to prevent condensation.  Hawk has 3" of fire resistant polyurethane foam sprayed in everywhere above the cabin sole.   The cabin sole has 1" of foam in it and in extremely cold climates we put inexpensive carpet over it. All the windows, ports and hatches have inside double panes (of 6mm acrylic sheet) which completely stops condensation.  Top of Page

20. Do you have a watermaker?

There is quite a bit of discussion about this in the various articles on Boats & Systems & outfitting.  But the short answer is no, we have never felt the need on either boat for a watermaker.  We believe it is critical for voyagers to adapt their lifestyle to their new seaborne environment, and part of that is learning to conserve freshwater. It is much simpler and more sensible to work with your new environment, and learn from and adapt to it, than to try to use fossil fuels and complex systems to bring your shore lifestyle to sea.  It is just barely possible to take an ashore lifestyle out to sea, and we know a few people who have, but you end up with a boat that over the long-term requires too much energy generation and is time consuming to maintain.

Our primary source of fresh water is rain catching.  We originally tried various tarp configurations to catch rain but quickly discovered that when it is raining hard it is often blowing hard and most of the water is blown off the tarps. At anchor we clean the decks with a salt water spray, let the rain rinse the salt off, open the deck water fills, put a wet towel just aft of them to create a dam, and the fresh water just pours in.  Using the decks gives us much greater surface area than any tarp and we have frequently caught 50gals in an hour.  If we are sailing with too much heel to use the deck, we catch water off the mainsail.  If we are not close hauled and don't need a perfect sail shape we can either drop the halyard a little (and pull down on the cunningham) or top up the aft end of the boom a little, both of which create a gutter along the bottom of the sail from which the water will pour into a big bucket.

We can see the possible value of a watermaker for extended cruising in very dry areas (Baja, the Bahamas, the Red Sea) although even in those places water is available and at such a low price that a watermaker cannot be economically justified. One can only be justified by the extra convenience, and this can be difficult after you factor in the extra maintenance and gen-set running.  We are puzzled by the cruisers who run watermakers in other places (most of the world) where free, clean rainwater is easy to catch.  In Costa Rica we could catch 200 gals/week of rain water with almost no effort yet there were boats running watermakers anchored right beside us.  Top of Page

21. Do you use your windvane much?

On Silk we used our vane about 90% of the time.  On Hawk it has been much less, somewhere in the 33%-50% range.  We believe that a vane is one of the most important pieces of gear on a cruising boat under about 45'.  It will steer offshore 24x7 reliably, quietly, using no energy and teach you to sail better by forcing you to balance your sails.  There is nothing else you can buy that will do all that. For coastal sailing they are much less satisfactory as the wind direction is often less stable and the boat will be in danger of hitting something if it wanders off course.

On boats bigger than about 45' and especially high performance ones, a windvane will be less satisfactory - it will be less reliable because of the higher loads and steer less well.  However, it is still essential that these boats have complete self-steering backup - either an entire spare autopilot and spare battery charging system (powerful enough to keep up with the autopilot), or a windvane.  Backup to our autopilot is the primary role the vane has played on Hawk, along with saving fuel (less battery charging) on our longer passages.  Top of Page

23. What lessons can be learned from new cruisers starting out down the west coast?

We have noticed three systematic deficiencies among the fleet of new cruisers starting out.  One is a lack of preparation/equipment for long dead downwind runs in big swells/waves.  Dead downwind in 20-30kts is very common along the main cruising routes, and you need a good boom preventer system and an easy to set/handle pole for the jib to sail well in these conditions. The second is inadequate self steering.  The autopilots that people had were undersized for the quite vigorous steering required in big waves and swell.  9 out of 10 boats in one harbor had broken all their self steering and were back to hand steering, which is very tiresome on a double-handed boat.  New cruisers outfitting their boats should make absolutely sure they have bulletproof systems in these two areas before moving on to spend money in other less critical areas.  The third was a noticeable lack of fundamental navigation skills.  Everyone was ok while their chart plotters were working and they could just 'point and shoot' but one boat's plotter broke and the crew had little idea how to navigate even though they still had a handheld GPS and a working depth sounder.  Virtually none of the cruisers in one harbor knew how to convert true courses plotted on a chart to a magnetic steering course.

When we arrived in French Polynesia and met new cruisers who had just completed their first long (~3000 mile) passage, we noticed three additional common deficiencies.  The first was not having a watertight plug for the foredeck chain pipe.  On passage, reaching in ocean-sized waves & swell in over 20 kts, most boats will have a steady flow of solid water splashes over the foredeck.  This will cause A LOT of water to go down an open foredeck chain pipe into the anchor locker/bilge.  If your anchor locker drains directly into the ocean (and is completely sealed from the bilge) this is not too much of a problem (although we don't really like this solution for other reasons). But if your anchor locker drains back to the bilge at all, you will do a lot of pumping.  On Silk we had a teak plug made up which exactly fit the shape of the chain hole.  The chain attached to an eye on the underside of the plug which kept it firmly in place.  On Hawk we have a neoprene plug (actually half a Nerf football) which we squeeze into the chain hole and we then wrap the outside of the windleass with plastic cling film.

The second was getting water into the engine, from either of two sources - a stuck anti-siphon valve or backfilling from the exhaust. Cruising boats tend to be very heavily loaded on long passages, thus low in the water, sailing downwind with big following waves that slam against the transom which can force water in through the exhaust.  All the commercially available anti-siphon valves I am aware of are poorly designed and will stick closed after a short while of salt water drying in them.  It is much better to remove the valve and put in a tall breather tube (see Nigel Calder's Boatowner's Mechanical and Electrical Manual for a discussion and drawing of this solution).  The exhaust pipe needs either a shut-off valve that is placed conveniently enough that it is actually used, or a pretty tall loop (but you need to be careful not to put too much back pressure into the exhaust system). It's nice to have a convenient way to drain the water muffler, so in violent conditions water will not get thrown from the muffler back into the engine, but this is uncommon and not as necessary as replacing the anti-siphon valve with a breather tube and adding an exhaust shut-off.

Third, when running in downwind squalls/crush zones (+40kts), many people rolled up their jibs and ran with double- or triple-reefed mains. This usually causes an unbalanced sail plan (the main causes the boat to round up), which the autopilot or windvane has difficult controlling.  After being forced to hand steer for a while, their crews are forced to heave-to or deploy a drag device in conditions where they could easily be making good miles.  In these conditions, it is better to drop the main/trysail entirely and run with just a foresail, either a staysail or rolled up jib.  This sail combination is much easier on the self-steering equipment.

In a recent study by a well-known marine insurance company of 150 sinking claims, several interesting statistics were brought to light. Probably the most interesting is the fact that for every boat that sinks while underway, four boats sink at the dock in their slips. There are two basic reasons for this. First, most recreational vessels spend considerably more time at the dock unattended than they do underway, and secondly when underway someone is onboard. This affords the possibility that the leak could be discovered and stopped before the vessel is lost. 50% of the sinkings were due to failures of below waterline through-hulls/hoses. Top of Page

24. What sailing programs do you really use on your computer?

1. XGate This is the compression/connection program we use for our Iridium phone.  This speeds up our satellite phone by about a factor of 10.  UUPlus offers a very similar service.  We had to get a ‘USB to serial port’ adaptor as the Iridium data cable has a serial connector and the new laptop did not have a serial port. 

2. Viewfax: This is a freeware GRIB viewer.  We used to use MaxSea to view GRIB files but it is too slow loading and clumsy (and had a printer port dongle - the new laptop does not have a printer port). 

3. WXtides32: This is a freeware world tides & current program, just as good or better than any of the commercial tides programs we have seen. 

4. Weather fax 2000 and Mscan Meteo Fax: These are two very similar weather fax receiver/viewers.  We mostly use GRIBs to get weather information, but occasionally in particularly tricky situations we will download a weather fax. It works by connecting any SSB receiver to your computer microphone jack with a simple audio cable.  You have to run the computer off its own internal battery when receiving a fax, as almost all of the cigarette lighter adaptor and 110vt inverters produce a ton of RF noise which blanks out the fax signal. 

5. Nebula: This is a windows interface for our Trimble Sat C. Sat C is viewed as an obsolete system but we like it because the equipment is industrial strength and very reliable, it produces free text weather twice a day all around the world, and offers a telex/e-mail service we use to give our families quick updates on our location.

6. StarPilot: This is a celestial and sailing calculator.  Many people would not have much use for this but I like to identify the stars and planets, and find it useful for planning passages with moonlight and arrival/departure times for twilight. Top of Page

7. Skype: This is THE way that cruisers make phone calls.  It's an internet phone service, about $.02/minute for international computer to landline calls.  You find an internet cafe or wifi hotspot, use your laptop or their computers with a headset/mic and make your calls. Very clear sound quality and esentially no dropped calls.

(Feb 9th 2008) I just had a Microsoft windows crash and had to reinstall windows and all my applications.  I tried to keep the program clutter down to a minimum, and installed: MS office, Skype, Viewfax, XGate, Nebula, WXtides32, Encarta & Britannica, and Turbotax. I did not install either of the weather fax programs as I have not gotten a fax in a while and also did not install StarPilot as I have not played with it in a while either. We still have MaxSea installed on an old laptop, but I cannot move it to my newer laptop because it has a printer port dongle and the new laptop does not have a printer port (only USB ports and I don't want a USB to serial adapter hanging from the machine all the time).

26. How much fuel, water and electricity do you use?

Our long term average for fuel (diesel) is just under .75 gal/day.  When we are not trying to conserve fresh water we use about 5 gals/day, and when we are we use about 2 gals/day [or - to even the comparison with shore house usage - 6 & 3 gals/day if we used a fresh-water vacuum-flush head rather than the typical saltwater head].  At anchor we use about 50 amp-hrs/day of electricity and on passage about 100 amp-hrs/day.  Our water consumption is pretty typical among cruisers (at least those without watermakers), our electrical consumption is very low relative to other cruising boats (200-300 amp-hrs/day would be more typical) and our fuel consumption is also low because we don't have to run the engine (or generator) specifically to generate electricity.  We live a comfortable life and the stunning comparison for me is how much less we use than if we lived in a house ashore.  The typical two car family uses 3.3 gals/day of fuel, [or  - to even the comparison with boat usage - 4.5 gals/day to include the fuel used at the electrical generation plant], 150 gals/day of water, and 15 kwatt-hrs/day (1250 amp-hrs/day) - so 6 times our fuel consumption, 12 times the electricity and 25 times the water.   Top of Page

27. What dinghy do you use/recommend?

On Hawk we have always used high-pressure air floor inflatable dinghies (a Quick Silver, a Zodiac and an Avon, with the Avon being by far the best) - for two reasons: (1) we don't like having the dinghy on deck during passage and the air floors roll-up relatively compactly and are easy to stow below and (2) in the high latitudes you can't tow the dinghy (because of high winds) but when you want to put out a stern line to shore you want to be able to get the dinghy over the side quickly, and we can just pick up the air floor and chuck it over.  We have a 4hp outboard and all the air floors have planed extremely well with one person, but not with two. I believe with 9hp they would plane with two just fine.

We did have a solid fiberglass rowing dinghy on Silk, and made custom deck chocks for it, which held it very securely and we never had any real concern about it in heavy weather.  It was both beautiful and a pleasure to row, and we intended to get one for  before we realized it would block the view through our hard dodger. So, we switched to the high-pressure air floors.  However, I think if one went to the same effort to make up some solid custom deck chocks for a RIB, it would be fine on deck while on passage.

We have friends who have been very happy with the aluminum and fiberglass floor RIBs, but not many people like the plywood floor boats.  The RIBs tend to need dinghy wheels for places with tides but no dinghy docks.  Our air floor is light enough we can just pick it up and carry it up the shore.  If tied to the boat with a painter, our air floor inflatable will take off and fly in about 35kts and fiberglass RIBs will do the same in about 50kts, so in either case you need to really secure them well in windy places like Chile.

The 'perfect' dinghy is just not made, and, like any boat, they all entail some compromises, but my feeling is that the RIBs are best for those who want performance and carrying capacity and the air floor inflatables for those who want light weight and stowability. Both work in the high latitudes, though they each have their drawbacks.  Top of Page

29. What sort of batteries & battery bank do you have?

We have tried Gels and AGMs and are back to using 6vt wet cells (golf cart batteries) for four reasons:  (1) they are 1/4 the life cycle cost of gels and AGMs (1/2 the price for 2x the life cycles), (2) they can be replaced anywhere, (3) they are impervious to accidental high charging voltage, and (4) their condition/charge can be tested cell by cell with a hydrometer to zero in on a bad/undercharged cell.  We initially used Trojans, but after getting a bad battery and poor warranty support we have switched to the middle priced brands (like Interstate and LTH) which seem to be just as good batteries with similar warranties at 35% lower price.  The 6vt batteries have generally thicker plates and thus longer life than 12vt batteries and are lighter/easier to move.

We have three battery banks: #1 is two 6vt batteries, for engine starting and emergencies; #2 & #3 are identical banks with four 6vt batteries in each (for a total of about 800 amp-hours).  They are normally parallel connected for one large house bank.  However, on long passage we switch from one to the other for house usage, so we have a complete bank fully charged as a back-up/spare in case the engine or alternators die. The engine bank is connected to the house banks with a Blue Sea battery combiner (a voltage sensing relay) so that it automatically gets charged when the house banks are charging.

See Battery Data for a collection of useful battery information. For a cruising boat at anchor regularly cycling their batteries (e.g. discharging them and then charging them), here’s the real world big picture on batteries as I understand it:

(1) Gels have roughly twice the price for half the cycles compared to wet cells. So, ¼ the ‘value’.  There is not yet a lot of experience with AGM’s on cruising boats but the experience so far is somewhat worse than gels (according to my sources at West Marine, and in the cruising grapevine).

(2) 6vt batteries have roughly 33% more cycles than 12vt batteries and you can get about 20% more amp hours in the same footprint (but they are taller).

(3) When I was last shopping for batteries, Trojans were priced 35% higher than the second brands (like Interstate and LTH) but deliver (in our experience) very similar performance, quality and support.

(4) Usage/charging patterns will make more difference to lifespan than anything else. For example: (a) Discharging the batteries to 75% of capacity (25% left) will reduce life cycles by 30% compared to discharging only 50% (Trojan). (b) Battery life cycles are halved for every 10ºC of rise in average operating temperature above 20ºC, and battery capacity is halved in cold temperatures (MasterVolt). (c) Consistently charging a gel battery .7vt above the recommended voltage will reduce battery life by 60% (East Penn). (d) Undersized jumpers/cables or dirty/under-torqued connections can reduce capacity by any amount.

So, for best lifespan/value the clear recommendation is buy ‘second brand’ 6vt wet batteries, be sure to use the optimal charge/discharge regime (shallow discharges, full charges with equalization cycles), use big cables and clean the connections (and batteries) regularly, and keep operating temperatures as close to optimal as possible. This is the hardest one to control but you can keep them away from engine heat but also warmed in cold weather.

However, if you are mostly on a dock with a shore charger plugged in, or have a lot of continuous charging from solar/wind, so that you don’t really cycle your batteries, then gels and AGM’s make more sense.  These batteries can have a 20 year maintenance-free lifespan if they are not cycled.  BUT, this is a very rare situation for an active/anchored cruising boat.

Also if you are racing where the ORC regulations are in force then sealed batteries are ‘strongly recommended’ to avoid the possibility of an acid spill during a knock-down. I personally think this is a drastic overreaction to a minor risk, and I think the ability to accurately monitor wet cell condition (and so not set to sea with a potentially bad cell) with a hydrometer (which you can not do with sealed batteries) is valuable from  a safety perspective and more than offsets the spill issue.

I have recently been exploring higher tech battery options for a superyacht refit project.  The top best battery experts agree that Li-Ion is the way to go right now if you have an unlimited budget, but we concluded that standard 2vt gel cells were the most reliable and easiest to replace option.  Top of Page

35. What do you do about lightning?

Lightning is fortunately pretty rare offshore.  You might see some crossing the doldrums and occasionally tropical line squalls have both water spouts and lightning. Lightning is much more common near specific coasts.  Florida, the Pacific coast of Costa Rica and Panama, Peninsular Malaysia on the Gulf of Thailand side, and the S. China sea off Borneo are particularly noteworthy spots.

We don’t do anything special regarding lightning. I have been convinced (by the science) that the little lightning brushes sold for mastheads are complete jokes and don’t do anything.  There is some discussion about faraday cages (see http://en.wikipedia.org/wiki/Faraday_cage) and putting handheld GPS’s in the microwave oven or wrapping them in tin foil.  This can’t hurt, but again the science suggests it is not a perfect cure either, a direct lightning strike could fry the whole oven and everything in it.  Metal hulls may act as partial faraday cages but we have know people to loose electronics inside metal hulls struck by lightning.

So, the bottom line is #1 fortunately lightning is rare offshore and #2 there is no sure fire method to prevent lightning damage, but using partial faraday cages (microwave ovens, other metal boxes, heavy tin foil wrapping, etc) is the most likely approach to be helpful.    Top of Page

36. What do you use for electricity generation?

We started out with three different generating options (two engine alternators, solar panels, and wind generator) and have dumped the wind generator and added a Honda 4 stroke generator (EU1000i).  The two main engine alternators (55amp stock alternator plus 100 amp Balmar) have been absolutely reliable and produce good power when we motor.  We like the two smaller units better than a single bigger alternator for several reasons - redundancy, more balanced loads on the engine bearings, and the ability to use single belts on the alternators rather than the twin belts the bigger units require.  The solar panel (80amp) has also been completely reliable and produces a good 3 amps in bright sunlight. We can safely leave it hooked to the batteries when we leave the boat and it keeps them from self-discharging.  It even produces decent power in the summer high latitudes.

The wind generator was very disappointing in both power output, and also in noise/safety.  Practical Sailor Magazine (July 2007 issue) did a four-day test of 5 different wind generators. The smaller units (29"-36" diameter blades) produced an average of 40 amp-hours/day and the bigger units (46"-47" dimeter. blades) produced an average of 64 amp-hours/day.  This test included two windy days out of four and the wind generators were sited in a clear wind flow and not a protected anchorage, so these numbers are likely higher that would be seen in the average cruising anchorage.  Despite that positive bias in the test, the output numbers are still quite low given the noise, safety, and mounting/windage issues associated with wind generators.  The safety issue is that you have a set of turbine blades speeding at near supersonic speed right above the cockpit.  We had a halyard swing into our blades and they shattered throwing razor sharp carbon pieces all over the cockpit.  Also I would never feel comfortable leaving the boat with one of these units running, in case a gale developed and the unit self-destructed.  If you are interested in upwind sailing performance, these units are also a problem as they need to be mounted up in the airflow and produce windage/drag.

The solar panel and the engine alternators have met our energy needs for nine years, but we recently decided to add the Honda (1000i) 4 stroke generator for three reasons. First, Beth has upgraded her laptop (faster processor and bigger/brighter screen) and it now draws 5 amps, which has significantly increased our daily usage when she is writing all day. Second, we are planning to spend the winter in the Beagle Channel, where there will be limited sunlight and we will not be motoring much so our normal generating capabilities will be reduced.  Third, we were anchored next to a French boat (an electrical engineer - the developer of the NKE instrument systems) who had a Honda 4 stroke generator and we were impressed with it's low noise, small size, reliability/ease of maintenance, and efficient fuel economy.  Honda has more powerful units but the 1000i is the lightest (easy to stow and move) and quietest.

We have now used the Honda for a year, and it continues to be a very impressive piece of equipment.  It has been absolutely reliable and the only maintenance is an oil change every 100 hrs (not even an oil filter).  My only three improvement suggestion for Honda would be: #1 to make the oil fill port more convenient - both for filling and draining the oil, and #2 make the rubber feet non-marking.  Right now they are black rubber that leave marks on the deck and I have to put a towel under the Honda to prevent black marks on deck. And #3, the fastners used are not stainless, so its important to keep the Honda of of salt spray and give it an occasional WD-40 wash-down.

We had planned to use the Honda only at anchor, but the last two passages we have used it also while while underway. Because of its light weight and small size, its turned out to be pretty easy and convenient. The Honda has a 'automatic low oil cut off switch', which will turn off the unit if you are rolling heavily.  I have been told that it is easy to open the front panel and disconnect a yellow wire to stop this, but I have found that the problem seems to be avoided more easily just by overfilling the oil level very slightly.

If we want to replace 120 ah/day, the 1000 watt unit will run for roughly 3 hours.  It would be nice to cut that run time in half by getting the bigger 2000 watt unit, but we continue to believe that the 1000 watt (40amps at 12vtdc) unit is the best answer because its very easy to stow and get out - much easier than the 2000 watt unit  (29lbs vs. 46lbs). The fuel efficiency is about the same between the two units (285 ah/gal for the 1000 and 290 ah/gal for the 2000). They are both about the same loudness (59db at rated load) - which is way less intrusive than our old wind generator at its rated load.

To generate the 120 Ah/day will take about half a gallon of gasoline per day.  So, it is obvious but easy to overlook, you need to start carrying significantly more gasoline.

There was a Dutch boat in the Beagle with one of these Honda's that had adapted it so that it could also heat the cabin.  The had two custom flexible stainless hoses made - one which slipped snuggly into the exhaust outlet and took the exhaust gas away and another which clipped over the cooling fan outlet and took the warmed air into the cabin.  It produced quite a bit of heat, and in that dual usage was enormously efficient.   Top of Page

39. What sort of navigation equipment do you recommend and which equipment should be visible from the helm?

We believe that electronic charts and chart plotters (or computer charting) are a useful advance.  They completely eliminate errors that can occur when moving positions between a GPS and paper chart. They also speed up decision making. However, because the GPS/plotter is likely to be on all the time, we are fans of a relatively small (5.5" diagonal), relatively dim (e.g. not sunlight readable) plotter screen, in order to keep the electrical draw down. We are not fans of large, sunlight readable, full color plotter screens as they simply consume too much power.  While it would be nice to be able to see the plotter from both the helm and nav station, our experience is that UV, direct tropical heat, humidity and salt spray will kill even the most 'weatherproof' marketed electronics. Over 10 years, we have lost two B&G displays while they were protected under our hard dodger.  We do have "course & distance to waypoint" repeated on our cockpit instruments so we always know where the route is. Things happen slowly enough on a sailboat that we have never worried about one of us going below to glance at the plotter if we feel the need.  One obscure feature we use quite a bit on our plotter is, when in a storm anchoring situation, to zoom way in and have it put a 'track' (e.g. a little red dot) on the screen every 10 seconds.  That gives us a graphical display of whether the anchor is holding or dragging.

So, our number one item is an energy efficient chart plotter in the nav station. In situations when you want a bigger screen (such as tricky long-distance route planning), using a laptop charting program makes sense as most of us will have a laptop on board anyway. We have MaxSea on a laptop and I sometimes use that for complicated route planning.  We also fire it up when we are navigating in difficult waters and have the engine running (so the extra amps don't matter).  There is also a 'free' 2-CD version of C-map's complete world chart catalog floating around, and many cruisers have a copy. (My understanding is that it was released some years ago by C-Map as a demo version of a big ship plotting program and C-map did not realize how useful it would be, even de-featured, to us cruisers). 

A VHF radio is extremely useful (required in Chile) and would be our second 'essential' piece of equipment.  We have tried a sting of different handhelds and not liked any of them (the batteries are never strong when we need them and the signal strength is low even when the batteries are charged).  We eventually got a remote microphone on a long cord for the main (nav station) VHF - we bring it up to the cockpit when we think we might need it.  Rather than the long cord, we could have installed a plug for it in the cockpit, but have found that cockpit plugs inevitably corrode.

Radar was very important before GPS and dead accurate e-charts.  Cruisers used to navigate by sextant and radio direction finding (and often just dead reckoning) until they were close to their destination and then turned on the radar to find out exactly where you were.  With GPS and dead accurate charts that's not necessary any more.  Radar is still useful for collision avoidance in fog but in most of the world dense fog is quite rare, and AIS is a better tool for avoiding big ships (at least in developed countries, where the ships are required to transmit AIS signals).  Radar is also useful for night navigation in places where the charts are not yet accurate, but that is a rapidly decreasing number of places (only Mexico and Chile in our recent experience).  It is almost always possible to make the same night navigation using the depth sounder and whatever visual clues are available. So, we are ambivalent about radar. We find it useful two or three times a year but could easily do without it.  We think AIS is a higher priority (but still not essential).

I have written a rough draft of an article on AIS. As I mention in it, I worry that people will install AIS and then focus their attention on the screen and be less careful with their deck watch. This can be disastrous as AIS/plotters do not show anywhere near all the hazards. The final report on the Flinder's Islet loss shows the very real danger of even experienced skippers focusing on the screen rather than on a deck watch.

We don't think a radar screen at the helm makes much sense.  There is the 'not truly weatherproof' issue mentioned above. In addition to that, in the foggy/rainy conditions when radar is most useful, I would not be able to see a helm screen very well with moisture on my glasses and on the screen, and if I am wearing gloves it would be hard to operate the controls.  We have never found it inconvenient to pop down to the warm/dry nav station to see the radar. We do think a decent size radar screen makes sense, as you are going to be trying to puzzle out the radar return in difficult conditions, and it is not going to be on that much (you can use 'standby'/'sleep' mode) so the amp draw is not as big an issue as with the plotter.

We like sailing instruments (wind speed/direction) for two reasons - first they allow our autopilot to steer to wind angle which is very useful both when close hauled and when running very deep, and second it allows us to catch wind speed and direction trends earlier than we would without the instruments.  But we have found our instrument systems to be more fussy than we expected (especially maintaining accurate speed calibration) and to be less reliable/require more frequent parts than we would like. (B&G wind calibration instructions)

We like having a barograph to help us understand where we are in a weather system.  A barograph is easier to use than a simple barometer.

We are not big fans of 'all in one' navigation systems because if one part of the system dies you have lost everything, and because as mentioned above we believe there are different optimal screens for plotters, route planning computers, radar, and instruments.

As to brand selection, the cruising sailor should pick products designed for the commercial market, not the recreational market.  Our usage is much more like commercial usage than recreational usage (which is typically only about 10 weekends of usage a year), and if we have to replace/repair something we are often some remote place where it is quite hard/expensive.  Just for example, that means RayMarine is low on our list and Furuno is high.  Top of Page

56. How should we evaluate our battery & charging requirements?

I just took a quick look at your electrical specifications.  With the newly revised double alternators and bigger battery chargers, your specs now represent what I would consider ‘the industry standard typical cruising configuration’. However, it is not optimized for continuous at anchor usage and will probably produce shorter battery life (perhaps 2.5 years) than I would like.

These calculations are pretty simple:

Step 1 is to calculate how much electricity you will use each day.  Typically separate ‘at anchor’ and ‘at sea’ calculations are done and you pick whichever is higher. The table below shows the basics of this calculations – you list all your major electrical equipment, how many amps each will draw, how many hours each will run, and add the amp-hours up.  The table below suggests you will use/consume 648 Ah/day at anchor & 763 Ah/day at sea.  In this calculation, I have intentionally erred on the high side in amps used because I know I have left off other electrical devices (vacuum cleaner, phone chargers, microwave oven, etc). Your skipper could do a more complete and comprehensive listing of equipment and hours he actually uses, but you will see that step 2 is somewhat crude so it’s not all that valuable to be exactly precise here in step 1.

Unit Amps to run one unit # of Units running at one time At Anchor: hrs used/day At Anchor: Ah/day At Sea: Hrs used/day At Sea: Ah/day
  A B C A x B x C D A x B x C
Masthead light 1 1 0 0 12 12
Anchor light 1 1 12 12 0 0
Windless 300 1 .5 150 0 0
Autopilot 10 1 0 0 24 240
Bilge Blower 1 1 2 2 2 2
Bilge pump 5 1 .5 2.5 .5 2.5
Cabin fan 1 4 12 48 12 48
Cabin light 1 6 12 72 12 72
Stereo 5 1 2 10 2 10
Chart Plotter 2 1 24 48 24 48
Depth Sounder .5 1 24 12 24 12
Fresh water pump 5 1 1 5 1 5
GPS/nav 1 1 24 24 24 24
Computer 3 2 10 60 10 60
Fridge/freezer 3 2 24 144 24 144
Radar 5 1 0 0 5 25
Heater fan 1 2 24 48 24 48
Communications 2 1 5 10 5 10
Daily Ah total 648 763

Note for other cruisers reading this.  These are 24vt systems for a 100’ super yacht. So, these numbers are not typical for ‘normal’ cruising boats.  200-400 daily amp-hours (at 12vt) would be more typical, but this table shows the calculation method that can be used by any boat.

Step 2 is to calculate the optimal battery bank size based on the expected electrical demand calculated in step one.  Three factors are taken into account: (a) is that you don’t want to discharge the batteries more than 50% because deeper discharges shorten battery life, (b) If you are plugged into shore power or running a generator boat you can charge the batteries back up to 100% but with alternators or limited generator time you will only bring them back up to 80-90% charge, and (c) Battery capacity declines over time and you want to build in a factor so you still have enough capacity after they have declined.  Each of the factors means you need a battery bank that is a multiple of daily demand. (a) & (b) combined mean you are often only able to use 30% of the bank capacity – between 50% and 80% charged state and this means you need a bank 3.3 times your daily usage. For (c) the industry normally uses an extra 20% (eg a factor of 1.2) to compensate for battery capacity decline with age.  The 3.3 from (a) & (b) times 1.2 from (c) gives you a factor of 4 – so you end up with a battery bank size 4 times your daily demand.

So, in this case 4 times your daily ‘at sea’ demand of 763 Ah equals a 3072 Ah battery bank. This gives you a bank that is cycled once per day for every day you are at anchor.

Cold weather decreases battery bank capacity (and warm weather shortens their life span).  This is factored into automotive battery sizing but not normally into yachts because the batteries are normally kept warm on yachts.  But if the batteries do experience temperature extremes – battery life will half for each 10C degrees above 20C (68F) and capacity , operation at 0C will cut capacity by about half.

Step 3 is to determine the alternator and charger sizes that will charge this bank as quickly as possible.  This in fact depends on the kind of battery you have - normal wet cells will accept less charge (25% of bank size) than Gel Cells (30-40% of bank size) which will accept less charge than AGM’s (40% of bank size) [note life span is the exact opposite, with AGM’s having the shortest, Gels the middle and Wet Cells the longest]. However, with these large battery banks, the industry typically uses the lower acceptance rate of wet cells even when the bank is Gels or AGMs.  So, you take the bank size of 3000Ah times 25% and you get a 763 Amp battery charger size.  You would optimally like the engine alternators to be this size but it is impractical.

Step 4 is to think about life span.  Batteries like to be fully charged all the time and will last for a long time in that state. So, the above calculations all work wonderfully if you plug into shore power a lot run the generator all the time or motor a lot, because then you keep the batteries full, and they will last perhaps 10 years. But each time you cycle the batteries (eg drawn them down and then recharge or let them sit overnight at less than 100% charge) you shorten their life.  Continuously at anchor, cycling them every day and bringing them up to only 80-90% charge, you are lucky to get 900 cycles (or 2.5 years) from these  batteries (industry data suggests 1000-1200 cycles from deep cycle wet cells, 600-900 from gels and 400 from AGM).  The batteries specified (2vt cells) will be even more difficult to replace than your current ones, as they will again be a custom order and I expect they will weight at least 150kgs each.

 There are four ways you can optimize/adapt to the at anchor situation and extend battery life.  First is obviously to make the bank larger, so each cycle is less deep.  On Hawk, in step 2, we used a factor of 8 rather than 4 in sizing our battery bank, and we do get 5 years battery life rather than 2.5.  The drawback to this approach is that it does double the size/weight of the battery bank. Second is to use lighter/inexpensive/commonly stocked batteries so they are easier to replace.  On Hawk, we use industrial fork lift/golf cart batteries which can be bought almost everywhere at industrial prices (rather than ‘yacht’ prices).  These are perfect for smaller battery bank’s (Hawk’s is 1000Ah’s), and you could build a 3000 Ah bank from them, but you would have to connect a lot of cells in parallel and series which creates problems if one cell is weaker than the others.  With wet cells you can fix that by equalizing but you cannot equalize gel cells (at least not in the same way) so it is not a recommended approach for big gel cell banks.   Third, is to add ‘green’ equipment that can provide continuous charging so the batteries are not cycled.  On smaller yachts in the tropics, this means adding solar panels and wind generators. But these will not work well in the arctic and in any case will not provide the amount of power you needs.  Fourth, is to provide a small, powered and quiet generator that over 24 hours will exactly replace the amount of electricity you consume.  There are of course small gasoline and diesel generators, which you could make very quiet, but they are not designed to run 24 hours and would require a lot of maintenance and might not have a very long life span.  However, given your cold weather agenda, the WhisperGen is perfectly suited to your needs.  It is a co-generation boiler driven system, designed to run 24x7, produces both heat and electricity, and is much quieter than an internal combustion engine.  One WhisperGen produces 1800 Ah’s/day (12 vts), so a bit more than replaces your daily usage, so you would not have to cycle your batteries and they should last for a long time (Top of Page)

57. How should we evaluate of heating & hull insulation requirements?

Heat loss calculations are important in three areas on a cruising boat: (a) in the fridge/freezer, to determine the required amount of insulation and size the compressor/holding plate, (b) when cruising in colder weather to determine the best amount of hull insulation and heater capacity, and (c) likewise in the tropics to determine the best amount of insulation and (if desired) AC capacity.

 

The essential first step in each case is a simple calculation to determine how much heat (BTU’s) will travel across the insulation each hour. This is a simple function of three factors: (a) the temperature differential between the outside and the inside, (b) the surface area exposed to this temperature differential, and (c) the amount of insulation (in R value) covering the surface area.

 

(a) Useful temperature values are: a freezer should be about -4F (-20C) & a fridge should be about 41F (5C).  Tropical water temperatures can be taken as 85F (30C) and a comfortable but chilly inside temperature in a cold climate could be 61F (16C).

 

(b) For a fridge/freezer you can directly measure the surface area of each side and the top and bottom and add them together to get the total surface area.  If you have thick fridge insulation the outside will be much bigger than the inside.  In that case, measure both the outside and the inside surface area and average them (add them and divide by two).  For the vessel surface area I typically assume it is a cylinder the length of the boat with diameter equal to the boat’s beam, and the surface area (cylinder with one end) is then = length x beam x 3.1415 + 3.1415 x (beam/2)^2

 

(b) R value is a measure how good insulation is. 1/R = number of BTU’s that will pass thru a sq ft of material per hour if there is a 1F degree temperature difference between the two sides. Foam insulation (of the kind typically used in fridges and hull insulation) can be taken as having an R value of 5 per inch (so say 3” of foam would have an R value of 15).

 

Once you have a handle on those three factors the initial calculation is simple.  You first figure the number of BTU’s that will pass thru one sq foot each day = R value x temperature gap in F x 24 (hours) and then multiply that by the number of square feet of surface area.  That’s a useful starting point, but it will produce numbers that are too low. If some surfaces have quite different R values than others (as is usually the case) then you need to calculate the BTUs for each surface separately and add them together. Also you need to add in a fixed heat loss when doors/lids are opened and from uninsulated components such as bilges or copper pipe which run thru the walls of fridges. 

 

For wintering in the Canadian arctic, the average outside temperature will be about -30C and the maximum lows will be -50C for December thru March. The table below shows the amount of heat you will require to raise the temp from -30C (& -50C) outside the boat to 16C inside the boat at 4 different thicknesses of hull insulation. It factors in the pilothouse windows as double paned with R10 and a small uninsulated bilge area and the effect of the aluminum frames bringing cold into the foam insulation.  

Required Heat (BTUs/day) Outside Temp -30C -50C
Insulation Thickness Inside Temp 16C 16C
10cm   42,000 btu 60,000 btu
15cm   30,000 btu 43,000 btu
20cm 25,000 btu 36,000 btu
25cm   22,000 btu 32,000 btu

 

Note: the typical cruising boat has only 1" (2.5cm) of hull insulation.

As an aside, when this model is applied to Hawk, which has 3" (8cm) of insulation, the results are 20,400 btu for -10F (-23C) outside to 60F (16C) inside.  Or put another way, just a little more than the output of one Reflek heater, which is exactly what we find in actual practice.

 

The Reflek (and the Whispergen) produce 20,000 btu of heat.  So, with 15 cm of insulation, three distributed units should do the job.

 

With a normal cooling water system, a 32kw generator will produce 18,000 btu inside the engine compartment, so a bit less than the reflek/whispergen.  But if you use a keel cooling system hooked to radiators inside the boat it can develop 80,000 btu of heat. The extra heat here can be used to keep the freshwater and diesel and thru hulls from freezing.

 

I would draw a couple conclusions from these calculations:

 

1. You really want the boat well insulated.  There is a big gain from 10cm to 15cm so I would say at least 15cm is desired. As an aside: 15cm is a common specification for freezer insulation and the temperature gap is roughly the same in a freezer and with the hull in the arctic. The specs suggest the insulation is stopped at either the waterline or cabin sole but you really want it brought down to the edges of the bilge sumps or have the sole heavily insulated. An uninsulated bilge would loose more heat than almost the entire rest of the boat.  You also need to make sure there is sufficient insulation not just over the hull skin but also over the tops of the frames, which are 15cm high. If you only go with 15cm skin insulation you then need at least 5cm added over the tops of the frames.  If you don’t put extra insulation over the frames, they will suck the heat out of the boat and leave frost lines/stains on the interior.  And the windows and doors need to be as insulated as possible – I have assumed R10 in these calculations.

 

2. I think keel cooling hooked to interior radiators is the only way to go with the generator.  If you put an air cooled generator outside (to avoid frozen thru hulls) you are wasting 100,000 btu. If you put it inside with a normal seawater cooled system you are wasting 80,000 btu’s and it probably will not work anyway as the water will be frozen outside the thru hull.

 

3. For sustained cold weather living, I prefer a distributed heating approach rather than a centralize one. The centralized diesel boiler/fail coil system is electrically intensive and has two major points of failure that would leave you with no heat and no way to repair without flying in parts. (Top of Page)

60. What should I do to make sure we don't get water in our engine?

Getting water into the engine block is a rather common problem among blue water cruising boats, but its rarely discussed. There are three reasons for this affliction occurring in boats that go blue water cruising who have never had it happen before in coastal cruising - usually the boats are loaded down more so the engine and intake and exhaust are deeper in the water, the boat will get into rougher and more rolly waters offshore, and the boat will be used more and often in hotter saltier water (the tropics) causing the anti-siphon loop to stick.

There are four sources of water than can get into the engine - two from outside the boat (from the raw water inlet and from the exhaust outlet) and two from inside the boat (from the water muffler/exhaust hose and from the water intake strainer/water intake hoses). Specific action needs to be taken.

1. By far the most common cause is the valve on the anti-siphon loop sticking closed, causing the engine to siphon water up thru the raw water intake system, filling the water muffler and then back filling into the engine.  Unfortunately essentially all the manufactured anti-siphon valves are pieces of junk - they either spray salt water around or stick closed, the first causing rust and electrical failures and the second filling the engine with water. Nigel Calder has outlined a solution in his Boat Owners maintenance and repair book -  essentially he recommends replacing the anti-siphon valve with a tall venting hose that can not clog. An alternate solution is to close the raw water intake seacock immediately after turning off the engine.  We use both solutions - having replaced the anti-siphon valve and turning off the intake seacock when we are at sea.

2. In a big following sea it is possible for a wave to slam into the transom and shoot up the exhaust hose and travel all the way into the engine. For some reason this seems to effect old race boats more commonly than other designs.  There are three things that can be done to prevent this: (a) a flapper valve can be put on the exhaust outlet at the transom, which will slam shut when hit by a wave.  These are helpful but not absolutely certain to prevent the problem. (b) In between the transom and the engine, the exhaust hose should loop up as high as possible above the water line (just make sure you don't exceed the engine specifications for back pressure).  This will create significant resistance to the water travelling from the transom to the engine, but is again not certain. (c) The only certain prevention is to install a valve in the exhaust hose and shut it when in rough water.  To make this useful you have to install the valve somewhere it is relatively easy to reach, because if its inconvenient you will not use it. People are often concerned about the potential for forgetting to open the valve before starting the engine.  This will in fact cause to harm to the engine - it either will not start or will sound funny and then shut down.  We did hear of one boat with a home-made water muffler that blew its top off when it was pressurized in this way. Again, we do all three of these things.

3. Even with both the intake seacock and an exhaust valve closed it is still possible to get water in the engine.  In the southern ocean in very rough weather we had the water sitting in the water muffler thrown forward and into the engine. The solution for this is to drain the water out of the muffler.  Most mufflers have a drain screw at the bottom but usually its in a very inconvenient  location - both hard to reach and draining the water around the engine.  I drilled and tapped this hole for a larger hose barb and ran the hose forward to the bilge sump with a valve on the end of the hose. So, in rough water we can open this valve and drain the muffler into the bilge sump (where the bilge pump will immediately pump it overboard).  It is also important there there are no dips or low spots in the exhaust hose beteen the water muffler and the engine, as water can collect in the dips and then potentially get thrown forward into the engine.

4. The final place water can come from is the water intake filter and pump/hoses. Water will be sitting in these places when the engine is shut down and the seacock is closed. The most common way for this water to get into the engine is thru a leaking water pump seal. If the seal is leaking, there should be small drain 'weep' holes that let the drips leaks out rather than into the engine, but sometimes these get clogged and the water can work its way into the engine instead. Part on the routine annual maintenance should be to stick a thin screwdriver into the weep holes and make sure they are open. It is also vaguely possible that water from this area could get thrown up thru the vented loop and into the engine, in the case of a knock down or such violent motion.  You could add drain lines (line to the water muffler) to this area to absolutely prevent this, but it is by far the least common source of problems and so far we have not thought it worthwhile to do so.

If you do get water into your engine, there will be no damage so long as you fix it reasonably quickly. The procedure is straight forward but not so fun to do in a big rolling sea.  (1) you close the intake seacock and drain the water muffler (usually a small drain screw near base) to prevent more water getting in while you are working n the problem. (2) Clean the top of the engine around the injectors (so that crud will not fall into the cylinders) and then remove all the injectors. Put them aside carefully. (3) Lay a towel over the top of the engine around the injector holes and spin the engine by hand a couple times (using a wrench of the nut on the front of the shaft). Water will shoot out the injector holes.  This will be a bit messy. (4) after most of the water has come out, spin the engine using the starter.  This will shoot the remaining water out. (4) Do an oil change - typically there is no water in the filter so you don't need to change the filter this time. (5) Put the injectors back in. (6) Start the engine (probably will need to bleed the injectors) and run it until it's at operating temperature. (7) Do a second oil change, and you do need to change the filter this time. And it should be all good to go.  You can see that it is worthwhile carry enough spare oil to do two or three oil changes while on passage.  (Top of Page)

63. With your anchor testing, why did you test a 2:1 scope and do the results apply to smaller anchors?

As I mentioned in the anchor test write-up, all three anchors are good designs and in a good bottom with generous scope all three will easily set and hold more than the working strength of our chain. So, the way to distinguish their performance differences is to test them in less than perfect bottom and scope situations, which is what I did in our testing.

3:1 - 4:1 is our 'normal' anchoring scope. We do in fact use 2:1 occasionally - in very tight situations where we are not expecting much wind and when 'parking the boat' temporarily to get lines and dinghy ready for a difficult med-moor or shore tie.  An anchor's ability to set at 2:1 scope is also reassuring because, if you are anchored with 3:1 or 4:1 and drag in deeper water or you anchor at low tide and have a bigger high tide than you expect, all of a sudden you have only 2:1 scope. In any case, we considered 2:1 to be the scope-related boundary condition worth testing and it seemed to highlight an important result. From the results (and our experience), it's obviously possible to use that short scope with a Bruce/Ray design but not with one of the roll-bar designs.

When I initially indicated my issues with short scope, one of the principles at ROCNA commented "Just FYI, originally my prototype had a 47 deg. throat angle, which over a period of time and testing I refined to 35deg. as being the ideal compromise.  The current anchors use 30 deg as it gives better results for the smaller anchors,, #20 and under, in packed grass or hard gravel. The large blade area means the optimum angle for sludge is not so critical. However, short scope setting suffers a little. The big anchors could have the 35 optimum as they don't suffer so much in difficult bottoms, but the differences are so small as not to justify production quality control issues with anchors and different specs."

That raises the second question - do our conclusions apply to the smaller anchors most people use? As the comment above indicates, there are scale effects with anchor designs, and the same design can perform differently/better in bigger sizes than it does in smaller sizes. So, the precise results of our testing can only apply to the precise anchors we testing. But, being less pedantic, we sailed around the world using a 20kg Bruce (and 20kg CQR) and found its performance completely consistent with our anchor results. So I would say that the general conclusions scale down at least to the 20kg size range.  (Top of Page)

68. After 11 years, is there anything you would change in your 'left off the boat list'?

Interesting question!  Sparked a spirited discussion between Evans and me.
 
Our basic priorities have not changed, so the “what we left off” list is still pretty much the same. Evans would not add anything.

 Beth would make some changes: For cruising in the tropics, I would love a very small refrigerator, just enough to keep things from spoiling for a day or two.  This has become more and more essential as the islands we visit have joined the refrigerated supply chain, making refrigerated and frozen goods available in many places and making it difficult to find un-refrigerated produce and eggs.  Of course, that would change our energy balance, but that has already changed as our computers have gotten more and more powerful.
 
It was the draw from our computers (up from 1.5 amps with my first laptop to 4-5 amps today, and we have two these days instead of one) that made us buy the small Honda generator last year.  That has given us the extra power we need with a minimum of space, complexity and cost (less than half a cup of fuel for an hour run time).  We would certainly consider adding a larger array of flexible solar panels, the kind you can walk on, perhaps on our hard dodger to increase the quotient of solar power if we were spending a lot of time in the tropics.
 
We might also add some sort of a below decks shower, though I don't feel as strongly about this.

The IPod is great - we download podcasts and listen to those over our radio.  We also love our Sirius radio that gives us BBC, NPR and other news programs when we're in the US.  Though it wasn't supposed to, it worked south to Costa Rica and we are now enjoying it again in the Caribbean.
 
An external wifi antenna is becoming a must..but we have managed without one so far.  (Top of Page

69. What sort of work do you need on Hawk after 11 years hard cruising?

WE have tried to keep Hawk in good shape while cruising (we had the mast/rigging stripped and rebuilt a couple years ago), and one of the advantages of keeping a boat very simple is that there is less work to do during a refit.  But time does catch up with some components of the boat.  Right, while I am in France, now we have the yard doing two projects - replacing wear parts on the engine (rubber mounts, water pump seals, alternator brushes and that sort of thing). I have just ordered a new Edson CDi steering system.  We really liked the Whitlock/Lewmar Cobra steering when it was new, but discovered over time that the engineering and construction details were poor. The Edson CDi system seems near identical but with all the details done properly. And the sails are off getting new chafe patches and stitching checked. That's all that's essential to get done.  When I get back to the boat, I will do a round of painting and varnishing and polishing, and it would probably be good to replace the double bunk mattress and the propane stove and some of the ropes. (Top of Page

74. Should we install a radar reflector?

Radar reflectors are recommended by most safety authorities (and required by ORC cat 1), but it is important to have a sound understanding of what is, and is not, happening when you rely on even the best passive reflector on a small vessel. Radar reflector test & Reflector Test 2 provide useful info on the performance (or lack there of) of various radar reflectors.  Related reports are the MAIB report on loss of S/V Ouzo, and IALA racon specifications which provides data on radar performance.

1. The 'Equivalent Echoing Area' presented by such devices is very small, by any standards. Various reliable authorities consider that an 'EEA of at least 10sq.m.' is necessary. That's effectively impossible, on a small boat, using a passive reflector at its optimum orientation.

2. The optimum orientation is very rarely presented to the (sweeping ) radar transmissions of an approaching vessel, for your boat will be heeled, pitching, and yawing all the time. So only a little of the Radar Frequency energy hits your device and gets bounced back, and only a little of the time.

3. If you are in lumpy seas or worse, your device may be effectively screened for part of the time, while you are down in the troughs - or the approaching vessel is. Or both.

4. Then there is the issue of sea clutter. This is the display of RF returns from the steep faces of breaking seas. Such reflections can be/are quite large, masking your little reflector's return. They are also intermittent, in that they don't persist in the same place. Many shipping radars' circuitry is designed to suppress returns that do not recur several times in the same place. That includes your weak return, bobbing and weaving and disappearing irregularly.

5. In conditions of strong sea returns ( say, F5 and more ), many operators will deliberately suppress those strong returns so that they have more chance of spotting a small but regular return, such as a <30' vessel fishing, pilots' launches, and such. That 'suppression' is likely to include your weak, intermittent and irregular return just when you want it to be spotted.

6. Many ARPA sets will not even process and display your radar return if it is weaker than the threshold that set is configured for, or it isn't there on X number of consecutive sweeps.

7. It is an act of faith that someone on the approaching vessel will both see, note and do something helpful about your radar return. That's been shown, many times and tragically, to be misguided. We need to consider the 'third-world' bridge watch keeper on a fast container vessel, with purchased Singaporean certificates and the 'sea clutter suppression' turned right up to avoid radar alarms and the need to do anything ( "I didn't see it" is one of the first excuses they learn ). Then there's the exhausted watch keeper who has fallen asleep in his chair, while the autopilot gets on with the job. Radar needs an active, responsible brain to interpret it.

Our conclusion is that while a radar reflector can't hurt, it is unlikely to be much help. We don't have one in our rig. (Top of Page

78. What have you done regarding LED navigation lights?

When we built Hawk good LED's were not available yet, so we put on the old standard Aqua Signal series 40 nav lights. The deck level (port and starboard bow, and stern lights) Aqua Signals have proven to be NOT waterproof and corrode easily and the fixture has to be replaced about every 3-4 years. This is a PITA, especially because we don't use them much (they are the 'motoring' lights). These I have just replaced with Lopos. Lopos are now the standard 'superyacht' nav light and are well built and well sealed but expensive.
The masthead aqua signal (Tricolor) has been reliable but we use it while sailing and it draws too much power. We have just gotten a replacement led bulb from Cruising Solutions to fit the old Aqua Signal fixture. The anchor light we prefer down at the boom level rather than up at the masthead and I have just bought two Bebi Owl lights for that purpose. We are just installing these lights. So I can't make any first hand comment on their real world reliability or performance, but they have gotten top marks from our circle of cruising friends who have used them. (Top of Page)  

86. What are your thoughts on emergency bilge/dewatering pumps?

Your first priority is to make sure your thru hulls, hoses, stuffing box and rudder gland and rudder post are 'perfect'. Your second priority is to carry plugs (for thru hulls and rudder post) and covering material for broken ports and hatches.  Then you can start thinking about pumps. Unfortunately, regular marine bilge pumps are pretty worthless except for a trickle of water, and serious pumps are either big or/and require quite a bit of power.  More complete answer here: dewatering pumps. (Top of Page)

87. How do you light your diesel heater?

We originally dropped lit matches or lit paper towels into the diesel in the bottom of the burner pot.  However, that causes carbon build up in the burner pot and is also quite a hit or miss procedure.

We now use an old fashion metal oil can and Methylated Spirits (but almost anything that burns would work – the hotter the better).  Squeeze just a drop of the alcohol to the top of the shout and light.  Then squirt into heater.  It will throw a flame thrower like splash of burning alcohol.  If I am having real trouble getting the thing lit I very occasionally pour a tablespoon of gasoline into the burner pot, before hitting it with the flame thrower.

oil can

 We saw another approach down in chile – take one of the small camping propane canisters and screw a thin long hollow stainless tube on it (apparently they make things like this to burn weeds from sidewalk cracks).  Light the tip of the stainless tube and stick down into heater – ignite the diesel and also pre-heat up the burner pot. (Top of Page)


“You can lose a ship anywhere.  You can lose a ship in so many ways.  And it isn’t trying to sail only easy routes that will save you, or adding auxiliary power – or hiring unnecessary tugs or tows.  Fight the shore bastards and look after the ship all the time.  That’s what you better do.”

Captain Learmont (28 years old and already captain for 6 years)