Small Recreational Trawler (e.g. Willard) Comments

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In discussing the experience of Zimmerman Marine's Willard 30 "Willie" round trip to Bermuda we must be careful to distinguish comfort from safety. The Willard 30 is an enormously seaworthy small boat. It is strongly constructed with a high bow and a canoe stern. It has a soft chined displacement hull with a full length 25% ballast ratio keel. It exhibits more than a casual resemblance to a Colin Archer lifeboat, those paragons of seaworthyness that plucked Norwegean fishermen from the North Sea. If forced to choose, I would rather endure a storm at sea in a Willard 30 than in any other comparably sized recreational trawler being manufactured today. That being said, the Willard 30 is not a particularly comfortable sea boat. The soft chines and ballasted keel that let it handle rough conditions offer little in the way of form resistance to rolling. While the boat would probably survive a 90 degree knockdown, as would very few other stock trawlers, periodic beam waves encountered in relatively moderate winds excite an uncomfortable resonance that can roll the boat through a 60 degree arc. My own Willard 30 has a measured roll period of 3.5 seconds. This is in the range of periodicity of waves produced by winds of about 20 kt., almost normal for offshore Atlantic conditions many times of the year. Any Atlantic coastal voyager is familiar with the ubiquitous NOAA forecast of 5 to 8 ft. waves and 20 to 30 kt. winds. While survival is rarely a question, comfort often is. The Willard is not to blame for this roll propensity. ANY boat of comparable size would behave similarly. It's all a function of wave height and period and boat dimensions. You can't fool Mother Nature. Willie's use of paravanes offers some roll relief but in severe weather they may represent more hazard than help. My own Willard, the Horizon motorsailing model, will heave to with a heavily reefed mainsail and a storm jib, but that solution is denied to the more modern Willards with the same hull. In the few instances in which I have been faced with similar nearby storm conditions as those being encountered by Willie on the return trip, I changed course to ease boat motion, regardless of my destination. If conditions deteriorated further, I waited out the storm tethered to a small parachute sea anchor. At a top speed of 7 kts, a Willard 30 can't outrun any storm so you have to depend on the boat's ultimate seaworthyness. But if it was me, I would have waited for a more favorable weather window on the return trip from Bermuda. ----------------------------------------------------------------------------------The Willard Horizon has an upper steering station which offers unexcelled visibility, but little protection from the elements. Still, using a removable Bimini or a garden umbrella, it is perfect for fair weather cruising. The only problem is that it has no instruments whatever. Here is how we coped.

Engine RPM: Of course the obvious thing would be to place a tach in a makeshift panel but that would have required installing an electrical tach sending unit in place of the mechanical takeoff of the old Perkins 4-107. It would also mean replacing the mechanical Stewart Warner tach on the instrument panel below. I opted for using a Cat Eye Velo #2 bicycle speedometer/computer, on sale for $25 at the local bike store. This little pillbox sized computer is designed to measure bike wheel RPM with a magnetic sensor and display speed, distance, time of day and trip time to the rider. It is self contained with a digital LCD display and an internal battery lasting two years. I epoxied a tiny bar magnet to the prop shaft and threaded the sensor wire to the computer unit. Since the computer is designed for all types of bikes, it can be calibrated for wheel sizes from 10" to 32". By telling the unit that the wheel circumfrence was 123.6 cm, the speed readout of shaft RPM becomes equivalent to 10 times the boat speed in knots. A magic marker decimal point on the computer dial reminds me that the Willard is not a Cigarette drug rummer. Most important,the indication of shaft speed lets me know when the gear is truly in neutral since the speed readout drops to zero even though the engine is running. The use of the clock, trip time, and distance facility are self evident. Depth: I simply fastened a Humminbird 100SX fishfinder/depthmeter to the top of the wheel housing. The transducer is located on the engine compartment sole in a big glob of silicone rubber. This was intended to be temporary, but it has worked so well over the past two years that I have never bothered to use a permanent mounting. I can't say enough good things about the little Humminbird ($89 at WalMart). It is waterproof, reliable, measures depth to 200+ ft, has backlight illumination, and finds fish. Ten years ago the same capability would have cost $1000. Navigation: At last I found a good use for my obsolescent Garmin GPS 45. This hand held GPS worked fine for position finding except that it was slow to acquire satellites from a cold start and consumed AA batteries like cocktail peanuts. Essential to the use of the Garmin as a permanent instrument is a fuzed three outlet 12v. cigarette lighter fixture (Radio Shack) connected to the boat's 12v buss. The Garmin is now fixed in a mount and, using the Garmin accessory cigarette lighter adaptor, runs directly off the boat's house battery. With the several DC outlets available on deck, I can plug in the Garmin, a hand held VHF transceiver, and a spotlight or portable CD player. I can even use my laptop when steering. The Garmin gives location, speed, compass heading etc. Because it is always on when cruising, slow satellite acquisition is no problem. The only thing I havn't figured out is how to rig a permanent sun shelter that will work when sailing. How have other Willard owners with an upper steering station provided remote instrumentation?

----------------------------------------------------------------------------------For those waiting with earballs wide open for the sound level comparisons of the new Linssen fast fiberglass luxury craft and my ancient Willard 30 Horizon here are the results: Linssen: twin 400+ hp Volvos, speed 30+ knots. Sound pressure reading in engine compartment is approximately 116 dB. Sound pressure reading in cabin and wheelhouse approximately 73 dB. a decrease in sound pressure of 43 decibels. This is roughtly the same as would be provided by a 12" thick brick and concrete wall between the engine room and the cabin. Willard 30: Perkins 4-107 at fast idle, 1000 rpm. Sound pressure reading in engine compartment approx. 96 dB. Sound pressure reading in wheelhouse, engine hatch open, approx. 94 dB. Sound pressure reading in wheelhouse, hatch closed, 92 dB. Sound pressure in cabin, 88 dB. Sound pressure on deck, 84 dB. Since the engine is just below the wheelhouse floor, it is obvious that the boat structure provides negligible sound attenuation. On the older Willards, sound insulation was most notable by its absence. According to current OSHA regulations, I should be wearing ear protection for extended cruises on my Willard. All the above Willard readings above were taken on the C scale of my trusty General Radio 1565A sound level meter. The C scale of a sound level meter has essentially a flat response and measures all the sound impinging on it, regardless of frequency. It provides a reasonably good physical measure of the ambient sound pressure. But the human ear is far less sensitive to low frequency (<100 cps) and high frequency sounds (>6000 cps) than to sounds of middle frequencies. Sound level meters also have an A scale which corresponds to the sensitivity range of the human ear. This is the scale used to measure the annoyance of ambient noise. The A scale readings on my Willard were: Idle: Wheelhouse, engine cover open, 89 dBA. Engine cover closed, 72 dBA. Cabin, 68 dBA. Engine at moderate cruise speed, 1800 rpm: Wheelhouse, engine cover open, 90 dBA. Engine cover closed, 72 dBA. Cabin, 68 dBA. Outside on deck, 60 dBA. This is not sailboat quiet but it isn't too bad, especially on deck. Why, you may well ask, is there such a drastic difference between C scale and A scale readings? And why does closing the engine hatch make only 2 dB difference on total sound pressure (C scale) but18 dB difference in noise annoyance (A scale)? The answer lies in the characteristics of the noise generated by my diesel engine. Most of the noise of a 4 cylinder diesel is in

the low frequency range, generally peaking at about twice the crankshaft rpm. At a moderate cruise speed the Perkins 4-107 generates most of its noise and vibration in the 30 to 100 cps range. Noise in this low frequency range is hard to block without using a good deal of mass in the sound barrier. Vibration of fiberglass panels is easily felt. The engine hatch, even though it is of 3/4" plywood with a 1/2" sound absorbing fiber layer attached to the bottom is largely ineffective. Attenuation of this type of noise requires soft engine mounts and a flexible coupling between engine and propshaft. It is really a problem of vibration control rather than noise control. This is the total sound pressure the meter's C scale is picking up. But the A scale, weighted to the sensitivity of the human ear, ignores that low frequency noise. It is most sensitive in the range from 100 cps to 6000 cps, with maximum response around 1000 cps. Noise in this frequency range is relatively easy to block with modest sound treatment. Shutting the engine hatch makes a big difference. The fiberglass panels which vibrate so readily with low frequency noise don't shake at high frequencies. There is almost no difference in the dBA readings between idle and cruising. The high frequency sound just isn't getting through. I can't say that my Willard is quiet, but the noise is tolerable except when trying to sleep below decks with the engine running at a fast cruise speed. It doesn't have the sound attenuation of the Linssen, but quiet comes at a steep price. Just to put these sound level readings in perspective, a jet plane taking off generates 140 dB. This is painful and more than a few minutes exposure causes ear damage. A rock band with amplifiers turned up high produces 120 dB. Rock musicians exposed to this noise level often have serious hearing loss. A New York subway car screeching around a curve produces 95 dB. The occupational noise level that OSHA declares is the maximum for a worker without ear protection is 80 dB. A noisy office is about 75 dB. Residential indoor noise during daylight hours in a big city is about 70 dB. The noise in the front seat of my not too expensive Subaru is 65 dB when driving within the speed limit. The lapping waves and wind noise measured today on the deck of my boat was 56 dB (C scale). My semi-rural living room, measured last night with the stereo and TV off, was less than 50 dB. Remember that the decibel scale is logarithmic. Every 3 dB change up or down doubles or halves the sound pressure level. ----------------------------------------------------------------------------------I've kept a log of fuel consumption and speed over the past few years and I have fairly accurate data on the performance of my '74 Willard Horizon. The boat has the stock Perkins 4-107 engine and a 2.57 reduction gear. It turns an 18"x14" prop. The cruising displacement is listed at 16,000 lbs but

since I don't always keep the tanks topped and the larder fully supplied, I suspect that the actual displacement is closer to 15,000 lbs. Speed is measured on a Garmin GPS 48 and verified from time to time by clocking the time to travel a measured mile between shore points. RPM is based on the tach reading which seems to be quite accurate (i.e. probably no more than 50 rpm error). My fuel tanks hold 120 gallons, plus a little bit of reserve. Here is the data: RPM 1300 1500 1700 1800 1900 2050 2100 2200 2400 2600 2800

Kts. 3.8 4.4 5.0 5.3 5.6 6.0 6.1 6.4 7.0 7.6 8.2

S/L ratio 0.73 0.84 0.95 1.01 1.06 1.14 1.17 1.23 1.34 1.45 1.56

Gal/ hr. 0.20 0.32 0.46 0.55 0.65 0.82 0.84 1.11 1.27 1.63 2.04

Theoretical range 1876 1394 1076 956 856 Measured on a 1400 mile ICW trip. 731 604 553 468 401

All these are in reasonably calm weather conditions. I usually cruise at 6 kts. The boat will actually hit 8.2 kts at 2800 rpm but the engine throbs, the stern buries, and it throw a wake big enough to make shoreside residents fear a tsunami. For long passages, the optimum speed seems to be 5 to 5.3 knots. This will give the Willard its advertised 1000 mile cruising range. ----------------------------------------------------------------------------------Last weekend was particularly breezy with a 20 kt. NW Canadian wind stirring up 3 ft. waves even in protected bays. My boat, at its mooring, was rolling through a 60 degree arc with a 3.5 second roll period. The gunwales were less than a foot above the water at the ends of the roll. I captured this thrilling moment on video to replay during those snowy days of midwinter. After a very hard row, we eventually made it to the boat in our dinghy and, with precise timing, scrambled aboard. Under power the Willard 30 still rolled about 30 degrees to each side when the waves were on the beam but by careful course selection we could diminish the roll to about half that, trading pitch for roll. I'm quite sure about the magnitude of the roll. We have a pretty accurate oil damped inclinometer from my sailing days fixed on the bulkhead.

Hoisting a small amount of sail made a considerable difference in the roll. The Willard Horizon carries about 280 sq. ft. of sail, 120 sq. ft. in the main and 160 in the large jib. A 50% reefed main (about 65 sq. ft.), sheeted amidships reduced the total roll angle to about 20 degrees, 15 degrees to leeward and 5 degrees to windward. Motoring with this stabilizing sail became almost comfortable. Owners of Willard 30s who are bothered by roll might well consider fitting a sail of comparable size as a roll damper. This is about the same size as a sail on a Sunfish. Don't use a Sunfish sail and mast, however, since the strain on canvas and rigging will be much greater. When the full main was hoisted, the roll dropped even further with no tilt to windward and about 15 degrees to leeward. With all sails up the roll disappeared almost entirely but the boat heeled about 20 degrees to leeward. All readings were in beam wind and sea conditions. Incidentally, the Willard Horizon can handle winds of up to 25 kts. without reefing since it is so undercanvased to begin with. In summary: steadying sails are not for propulsion and are effective in stopping roll in beam winds. I have found a reefed mainsail minimizes roll when motoring in choppy conditions. For PUFFIN that means about 60 to 70 sq. ft. of sail area. The sail is sheeted in tight amidships and offers no propulsion power. The boat takes up a slight angle of heel and and the roll is attenuated. It is far more effective, of course, to actually sail using the full sail area. In that case the roll disappears almost entirely. The boat carries 280 sq. ft. of sail on a low aspect rig, a large foresail and a smaller main. This is only about half the sail that a cruising sailboat of similar specifications would carry and PUFFIN can be considered to be sailing under perpetually reefed conditions. It can best be considered a 30/70 motorsailer. On a calm day and with a clean hull it requires 22.6 hp. to drive PUFFIN at its 7 kt. hull speed. This estimate is confirmed by careful fuel consumption measurements kept over several years. The best speed I have ever gotten under sail alone in a beam wind is 5 kts. It takes approximately 8.2 hp. to move the boat at this speed under power. Sailboat designers estimate that sails can produce about 1 hp. for each 27 sq. ft. of area under good conditions. The 260 sq. ft. of sail on PUFFIN should generate about 9.6 hp. of propulsive effect. The 1.4 hp. difference between the 9.6 hp. generated and the 8.2 hp. required to move the boat at a 5 kt. speed is undoubtedly due to the drag of the large non-feathering prop. In essence, the prop drag costs 15% of the generated sail power.

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