The Norsea 27 has for many decades been quietly acclaimed as a great little sailboat. The obvious unique feature of the Norsea of course was that it was marketed as a trailerable blue water cruiser, and did prove to be quite a good little ocean cruiser. Lighter weight fin keel boats of the same size certainly are a lot faster, but the Norsea does have a certain measure of functionality and practicality that makes the 40 year old design interesting and relevant.
Hull Shape
The Rig
Motoring Performance
Comparing the Norsea to Fin Keel Boats
The hull form of the Norsea 27 is called a cut away forefoot, or a three quarter keel. The Norsea in fact has an extremely radically cut away forefoot, and this is a large part of what makes it a good sailer. With the center of effort of the keel far aft the Norsea sails like a real sailboat, and can carry a large amount of sail. The radically cut away forefoot also contributes to responsive quick handling and good control on all points of sail. Other features of the Norsea hull are a large rudder placed far aft and a rather deep four foot draft as compared to the narrow eight foot beam. This rather deep keel with a generous helping of 3000 pounds or more of lead ballast gives good stability in rough conditions as well as providing rather efficient lift for sailing to windward. The Norsea was originally designed to have a finished displacement of 7,100 pounds with 2500 pounds of ballast, but as is often the case the project came out heavier than anticipated. With a typical cruising weight of around 10,500 to 12,000 pounds even the optional extra ballast that was included on most Norseas yields a ballast to displacement ratio not much better than 25%. The claimed displacement of the empty Norseas with the extra ballast is usually listed as 8,600 pounds. Weighing the empty trailer and then weighing Eva on her trailer several different times I estimated that she weighed just over 9,000 pounds empty and 10,500 pounds once fitted out with most of her new equipment, a modest load of cruising gear, full tanks and no provisions onboard. The rather deep keel for such a small boat helps considerably with keeping all that weight upright, but the hull form stability of the Norsea 27 is also quite high. The large flat middle and aft sections of the hull provide a substantial amount of hull form stability without the Norsea looking like a flat bottom boat. What this adds up to is an ability to carry sail quite well with the tall mast.
The Norsea 27 came standard with a tall 34 foot mast, but was also available with an optional shorter 31 foot mast. Eva's mast was replaced in about 1986 with a 35 foot tall Le Fiell that is a bit heavier and a lot stiffer than the stock mast. With the extra weight aloft and slightly bigger sails Eva sure can bend over when the wind gusts, but for the most part the stability is sufficient and she sails upright with only a small amount of heel. The other main feature of the Norsea rig is the rather far forward placement of the mast. This far forward mast location and full length boom make for a large mainsail that works particularly well for sailing off the wind. Using the mainsail as the main driving sail downwind is generally a tricky operation, but the Norsea is well suited to this type of sailing. With a rather small 110% jib sheeted in tight and flat and the boom hiked far out to leeward the Norsea 27 runs downwind better than most boats not flying spinnakers. With the burly Le Fiell boom we were able to essentially sail Eva as a mid boom sheeted boat using a three to one vang down to the lee rail. The advantages of the large main and flat sheeted headsail are numerous. One big advantage is not having to go up on the fore deck for normal sail handling, although I often did re-route the jib sheets in between the stays for running downwind in rough seas. The really big advantage of running downwind on a big main and a flat sheeted jib is the stability afforded by this sail plan. The "Vee" shaped sail plan with the point of the "Vee" pointing into the wind is an inherently stable shape that resists direction changes better than a spinnaker or a poled out genoa. This inherent stability helps out a lot with the overall handling of the boat, but the big mainsail all out on one side does tend to cause roundups if all the sail is carried in too much wind. With good functioning self steering Eva is however able to carry the whole mainsail in enough wind to surf and skitter down the waves averaging over seven knots. In general though anytime the average speed climbed above about 5.5 knots in the open ocean the ride became quite wild with lots of water on deck. We did however have some 24hour runs of 130 miles, and we even had an 800 mile week once. In protected waters reaching at 7.5 knots is common place, and despite the heavy weight the Norsea 27 is not strictly limited to the 6.5 knot theoretical hull speed of the 23 foot long waterline. Where the tall rig and big mainsail really shine though is in very light wind. By flying a big overlapping genoa with the big mainsail we were able to sail along at two to three knots in wind so slight that the surface of the water hardly rippled. And getting up to five knots took such a small amount of wind that we often were able to make 40 mile daylight coastal cruising runs entirely under sail in conditions so calm we hardly felt any wave induced motion of the boat. Of course a more typical coastal cruising day with ideal conditions for Eva involved sailing out with the land breeze for three hours of light reaching at two to three knots followed by a few hours of flat calm motoring and then three more hours of two to three knot reaching on a building sea breeze with the grand finale of screaming into port at 5.5 knots on the big eight or ten knot puff of sea breeze in the late afternoon. This ideal sort of day was best attempted with just a 20 or so mile run to the next harbor. The point here is that the Norsea 27 is an extremely good light wind boat, and where the Norsea 27 shines is in the absolute lightest of wind that requires the patience to sail along at just two knots.
The Norsea 27 is generally a good motoring sailboat for a variety of reasons. The low placement of the engine and the only slight down angle to the propeller shaft makes for good maneuvering characteristics and efficient drive from the propeller. The very low placement of the propeller also keeps the prop in the water in rough conditions, and the Norsea generally does not suffer from the prop coming out of the water under any conditions. The shape of the hull with the rounded off stern and radically cut away forefoot keeps the wetted surface area low for efficient motoring at low speeds. The success we have had with motoring Eva long distances is also due to our large 40 gallon fuel tank and the small 331cc displacement Yanmar SB8. The old Yanmar SB8 does not really do all that well under any conditions, but being able to cruise along at four knots burning just 0.15GPH seemed pretty good compared to other sailboats. Most Norsea 27s have been retrofit with two cylinder Yanmar engines using inline type injection pumps that just won't run at less than a quart an hour, with 0.35GPH being more typical. The small displacement of the Yanmar SB8 is a big part of this difference, but the regulator valve type injection pump on the Yanmar SB8 also contributes to the flexibility of the engine. Not only can the SB8 putt along at 2000RPM burning 0.15GPH but also remains more efficient up at 2800 to 3000RPM requiring less than a third of a gallon per hour to do five knots in flat water. When punching into wind and waves is required the Yanmar SB8 leaves something to be desired, but it does scream at 3200RPM putting enough power to the water to get waves smashing over the bow while burning only about 0.4GPH. A two cylinder Yanmar can put a whole lot more power to the water, which is considered indispensable by most owners, but the fuel consumption does also go way up to close to one gallon per hour.
The Norsea 27 is a whole lot heavier than high performance boats of the same size, and especially when loaded down with thousands of pounds of cruising gear getting above hull speed just does not happen easily. Lighter boats can routinely sail at substantially higher speeds in good wind, and also much more easily come up to six knots in light wind. Still though there are some advantages of the Norsea 27. Very light wind performance remains quite good, and light weight racing boats in the 23 to 40 foot range typically have to fly spinnakers to do better than a well sailed Norsea 27. When the wind is too far ahead for spinnakers the comparison is a bit different because the attached rudder of the Norsea 27 just is not as efficient for going up wind as the fin keels and spade rudders of racing boats. Still though a Norsea 27 can often give much bigger rather high performance boats a tough time close reaching in the lightest of wind. What is going on here is that the wide beams and flat bottoms of racing boats add up to much higher wetted surface areas, and in the lightest of wind the round little Norsea with her big sails just glides forward with amazing ease. Then there is the rough conditions advantage of the attached rudder. The long keel and huge rudder placed way far out back give the Norsea an amazing ability to stay pointed downwind in big breaking seas, and recovery from broaches is normally quick and easy. Fin keel boats certainly can surf fast downwind in big seas, but a sailboat up on a plane in the open ocean is the realm of daredevil racers of intense dedication. The Norsea on the other hand can tolerate all manner of abuse and mistakes by the crew with a whole lot less chance of disaster. The biggest difference really is in the situation of a broach. When surfing down big breakers at 11 knots driving on the mainsail a Norsea does broach sometimes. What it usually does not do though is "go shrimping" like other boats sometimes do. When a light boat comes off of the plane it is like a cork bobbing in the froth, and there is usually no way to get it pointed back downwind until the breaking wave has passed. On the Norsea the worst of broaches normally self correct as the far aft placement of the center of effort of the keel and rudder simply point the boat back downwind while it slides sideways on the mountain of breaking foam. In these situations the rudder of a Norsea 27 has been described as a "brake", both slowing the boat and turning it back down wind. Smaller rudders placed farther forward are much less effective in correcting from a broach that has already begun. Another significant advantage of the full keel over a fin keel that can't be ignored for long distance cruising is the better protection of the propeller from fouling. If a saildrive is used to place the propeller farther forward where it is better protected by the keel then maneuvering performance of the boat is severely compromised. If on the other hand the propeller is placed far aft where the stream of water directly hits the rudder for good maneuverability then it is very vulnerable to fouling by anything in the water. A detached rudder with a substantial skeg is a popular compromise for fin keel boats intended for long distance cruising, and this does substantially protect the propeller from fouling as well as protect the rudder from damage from groundings. The problem however with the detached rudder design is that it is highly inferior to the spade rudder for sailing performance, and in many situations is actually inferior to the cut away forefoot full keel. A fin keel and skeg hung rudder can provide the substantial advantage of a lower wetted surface area than a full keel boat, and if the fin keel is deep and short it can be much more efficient for going to windward than any kind of cut away forefoot full keel. For sailing downwind in the open ocean though many cruising boats with skeg hung rudders have very severe problems with excessive weather helm, a tendency to round up uncontrollably and poor recovery from broaches if they are pushed very hard. The problem is that the center of effort of the keel and rudder ends up too far forward on many boats with skeg hung rudders. Fin keel and spade rudder boats also tend to have rather far forward centers of effort for the keel and rudder, but the spade rudder is so much more efficient that as long as the boat's speed is kept up they stay well under control. With a skeg hung rudder though the rudder ends up being even less efficient and less effective than the rudder on a full keel boat, and combined with the far forward placement of the center of effort of the keel and rudder this leads to a boat that does not sail very well. The other problem with skeg hung rudder boats is that in the interest of shallow draft many of them have long short keels with just small cut outs between the keel and the skeg. This small cutout does not substantially reduce the wetted surface area, but does interfere with the efficiency of the rudder while also making the propeller more vulnerable to fouling.
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