Review of the Mariner XL from the Spring 1987 issue of Sea Kayaker magazine.
1987 Sea Kayaker

PHASE III
PADDLERS' TEST

FOR THIS THIRD Series we used a team of paddlers who came with experience ranging from twenty years to beginners. and in sizes from 5' 1" to 6' 2". The kayaks were paddled in the Georgia Straits, on the west coast of Vancouver Island, and in the surf of Long Beach in the Pacific Rim National Park. All paddlers were asked to write down their opinions immediately. either whilst paddling or the first thing on landing. The main areas for evaluation were portability, seating comfort and fit, construction quality, handling characteristics, loadability and general attractiveness of design. Paddlers were also required not to discuss the relative merits of the boats until their evaluation was complete.

As we had in our first and second series of tests, we asked our paddlers to be positive in their evaluation. It was not our business to seek out tiny nit-picking faults that occur in all manufactured products from time to time. We were basically looking to see how well the kayak fitted its role and to be sure we knew what each designer meant that role to be, we asked all those who supplied a boat to describe its designated purpose. (As in previously published tests, designer comments appear as a preface to each individual kayak review in the following pages.)

The three models made available to us for testing featured the following options. Wind Dancer and Pisces-standard package (includes bulkheads, hatches and rudder. Mariner XL-(Basic model with sliding seat option and the addition of rear hatch, pullout rear bulkhead and Cruising Package. The photographs shown for each boat are of the actual models tested by our paddlers.

An outline of options available, composition, prices and general availability concludes each kayak review; this additional information was supplied to us by the manufacturers involved and stated as current at the time of our going to press.

As well as being asked to provide comments regarding their craft's designated purpose and general product information, designers were offered the unusual opportunity to review our test results before their publication and to comment upon them at their discretion for the benefit of our readers. These remarks, published collectively, form the conclusion of our tests for this issue.

Our thanks go to B.C. Research engineers for their high degree of cooperation, to our team of paddlers for the keen interest they have shown in our program, and to the four designers represented here for their participation and willingness to operate within our deadlines.

Graphic of resistance graph and data -- Xlrvgrph.gif (33749 bytes)

[Added Note:Due to the poor quality of the scanned page we are reprinting the relevant part of it with the related text typed in below. For the measurements of the Mariner XL see Dimensions. At 4.5 knots the total drag was XL--4.99, Pisces--5.0, and Wind Dancer--5.5. Most paddlers with this gear load (paddler plus load--250 pounds) travel between 3 and 4 knots.]

Graph above enlarged -- Xlrvdrgr.gif (6614 bytes)

BAR GRAPHS TAKEN FROM UNSMOOTHED RESISTANCE FIGURES AT 2, 3, 4, & 5 KNOTS. Skin friction has been separated from residual resistance, this shows the dominant effect of wetted area at low speeds and the increasing effect of residual resistance as speed increases. Total resistance for each kayak appears at the top of each bar graph.

 

Picture of top and side views -- Xlrvpict.jpg (8324 bytes)

DESIGNERS STATEMENT

The Mariner XL is a versatile medium volume sea kayak built for demanding paddlers wanting the best in design, material, construction and custom options. Paddlers from 120 to 220 pounds, with up to size 12 feet and a 36" inseam, will find the cockpit both secure and comfortably roomy. We wanted the least possible resistance at cruising speeds without compromising features that inspire confidence in rough conditions: smooth predictable motions, dynamic stability in waves, control of sideslipping, and a gentle (no pounding) dry ride. The XL tracks positively yet will turn easily by tilting the hull with the hips for a ruddering effect. Used correctly (see manual) the windage balance, hard chines, swedeform hull, and instantly adjustable sliding seat/footbrace unit make a rudder an unnecessary appendage.
CAM AND MATT BROZE

Reviewers impressions of the
Mariner XL

HOT ROD seemed to be the consensus of our first impressions of the Mariner XL. Its sleek functional lines certainly look as though it has been designed to do something beyond the ordinary. Construction is sturdy; the two kayaks we handled varied between 55 and 60 lbs. with removable rear bulkhead, sliding seat, rear coaming hatch and pump strap in place. The demo model supplied for our paddler tests still looked good whilst the brand new kayak used in the B.C. Research test tank had a standard of finish well up with the state of the art. Neoprene thigh pads at the balance point also act as shoulder pads for a single person carry and toggled handles fitted to substantial U-bolts make a two person carry easy: So long as the seat was in the mid or rear position entry and exit even for our tallest paddler was quick and easy and the paddler's feet are automatically guided onto the footbraces by their attached side straps.

The kayak has a stable enough feel yet it responds easily to a leaning paddler. (According to our figures and with the exception of the Eskimo 18-6, it can be leaned further without tipping than any other kayak tested so far.) We found this responsiveness to leaning quite important when attempting to maneuver the boat quickly or in confined spaces. Partly as a trade off for its ramrod-straight tracking, turning quickly on an even keel requires considerable effort and it is far easier (as the comprehensive user manual describes) to either "knee" the boat or lean out onto the paddle stroke on the side opposite to the direction of turn. Paddling a chosen course either in flat calm or in swell and chop is straightforward with the Mariner XL. It paddles along easily with little tendency to yaw except in very difficult combinations of wind and sea direction and its responsiveness allows the paddler to reduce the rolling effect of cross seas with natural ease. Directional control in surf or strong winds and heavy seas is augmented by judicious use of the sliding seat. To get the best out of the system, however, would require more time and practice than our paddlers were able to allot. In any event, we did find the unloaded kayak to be more manageable on most courses in strong 20-knot wind conditions than the other boats with their rudders raised. It was in the surf that the XL excelled. With the seat in the forward position, some of our less experienced surf paddlers were able to stay on a wave longer and to turn off the wave with more control than they had previously with any other boat. Even our beginner, who had just learned to brace, could manage light surf without upset. With the seat in the back position she simply allowed the boat to broach when the wave broke and then when the wave turned to soup the aft keel took control, straightened the boat and whisked her. bow first. to a gentle landing on the beach. Riding the waves is so much a part of this boat that it was in great demand whenever we were running with following seas.

The kayak as supplied was equipped with a well fitted foam pull-out bulkhead aft of the seat and no forward bulkhead. Although it cannot claim to provide a watertight seal, the pull-out bulkhead proved quite effective in minimizing seepage into the rear compartment during our volume measurements. There is plenty of loading space with very easy access Both forward and aft of the seat. Our boat was fitted with the standard 4" screw-in Beckson type hatch on the foredeck and a 12" x 17 1/2" coaming hatch on the afterdeck. The fore hatch cover is attached by a lanyard that also secures a spare wing nut for the footbrace slides. The well sealed aft hatch has three separate components: a fiberglass lid, a vinyl sealing strip and a neoprene cover, none of which are attached to the boat. Of these, only the neoprene cover floats.

The Mariner XL is clearly a performance boat. A keen paddler, with practice and consultation with the comprehensive user's manual, will find the boat well able to meet its designer's aims.

Response from the Brozes:

WE LOVE IT. You've made it clear that the XL not only won't intimidate the rankest of novices but also won't make these paddlers feel they've "outgrown" it as soon as they've developed their skills. As for stability, why pay the price for more than you need? Your graph and testers' comments have reinforced our opinion that even beginning kayakers should seek "stable enough", (for fishing, having lunch, changing film, etc., even in chop) and avoid the penalties of excess stability-more resistance and less control (particularly when loaded).

Does anybody you know ever push a loaded kayak above 4 1/2 knots for more than a few yards? The resistance curves (from the 6 kayaks tested with turbulence inducers) indicate that at typical cruising speeds of 3-4 knots, the XL is 7 to 9% easier to move than the next best and 14-18% easier than one (and this without their rudders dragging through the water!) So if you’ve covered 20 miles in one of these other boats, the same effort would have taken you from 21.4 to 23.6 miles in the XL. Or, put another way, an 18% difference means that after 20 miles in the XL, you'd have saved enough energy to lift it (at 60 lbs.) to your car rack (5 feet) 250 times.

We notice you proved us wrong on one point. We've been under the impression that the XL was medium-volume as cruisers go. Evidently it is comparatively large. We should point out that although we personally don't prefer bulkheads and rudders, they are among the wide range of options we offer.

Thank you for your more complete explanation of what the stability graphs reveal. Secondary stability is not a myth, just uncommon. In the future, we'd like to see stability tests also done with a gear load to compare the relative increases. Our wish list also includes one five-knot run in the tank with only enough weight to simulate a paddler.

OPTIONS
Design in production since March 1985.
Standard lay-up: Vacuum-bagged with multi-knit rovings and reinforcements. Vinyl ester resin and reinforced gelcoats.
Other lay-ups available: You name it. Super heavy duty or lightweight with Kevlar and other exotic materials if desired.
Options: Completely functional deck rigging, bulkheads (permanently installed or removable); a variety of hatches, rudders, pumps, self-rescue devices, etc.
Approximate weight: Standard lay-up with sliding seat: 52-54 lbs. before options; hung seat model, 48-50 lbs. (Whether you need an 80 lb. boat or a lightweight, we’ll build it.

STABILITY CURVES

 Stability curves -- Xlrvstab.gif (3657 bytes)

THE CURVES SHOWN ABOVE represent righting moment in lbs. ft at angles from the horizontal in degrees--using Fred as our (simulated) standard paddler. Note 1: The origin of each curve represents the boat sitting upright. The point where the curve drops down to the horizontal line represents the angle of imminent capsize The area under each curve represents the work done in heeling the kayak and Fred to the point of imminent capsize. Note 2: Stability curves are not corrected for sea water. Seawater stability will be slightly less than for fresh water.

NOTES ON INTERPRETATION
STATIC STABILITY CURVES

WHEN WE MEASURE stability in the test tank all we determine is the righting moment of the hull with Fred (our standard inert paddler. weighing 150 lbs.) clamped in place. Figures are derived directly in lbs.ft. by holding the boat at five degree intervals in angle of inclination using a torque-measuring device until capsize point is reached. The figures are then corrected to allow for the influence of the bow clamp and then transferred to paper in the form of a static stability curve. A stability curve can reveal much more about a boat than merely the righting moments from which it was derived. But this can be confusing and, to help make the picture clearer. we have selected three curves to examine a little more closely. Our examples are the Arluk III and the Solander from the Fall '86 issue, and the Mariner XL from the current issue.

Stability curve comparison with Solander and Arluk III -- Xlrvstb2.gif (1919 bytes)

At first glance the superimposed curves of the Arluk III and the Solander look quite similar and you may wonder why our test paddlers found the Solander to be somewhat less stable (or more responsive, depending on their point of view) than the Arluk III--and why the Mariner XL was found to be similarly responsive to the movement of the paddler while its maximum righting moment is 36.9% greater than the Arluk III's.

At any selected point on these curves the righting moment measured in lbs.ft. may be read on the vertical axis, and the angle of inclination measured in degrees on the horizontal axis. The area under the curve to that point represents the work done in inclining the kayak to that angle and, if the angle is measured in radians (1 radian = 57.3 ), the units of work will be directly in ft.lbs. The slope of the rising part of the curve at that point represents the stiffness, which is the rate of increase of the righting moment as the angle of inclination increases. Units of stiffness come out as lbs.ft./degree. For a boat to be in a stable state, an increase in heeling force must be balanced by an increase in righting moment, after an appropriate increase in inclination. So stability requires stiffness and the two terms are often interchanged.

The slope of a curve can be derived at any desired point by drawing a tangent at that point, and that is a straight line coincident with the curve at the point of contact. Its value can be calculated by making a right angled triangle from this tangent and dividing the vertical height by the horizontal length.

If we now pull out some of these figures and compare them in percentage terms. the differences in static stability characteristic become clearer. The initial stiffness of the Arluk III is 39.6% greater than the Solander's and 2.8% less than the Mariner XL's. At an inclination of 8 the Solander stiffens considerably and becomes 32.83% stiffer than the Arluk III, which remains constant, 30.9% stiffer than the Mariner XL, and 85.4% stiffer than its own initial value.

When the inclination angle reaches 24 , the righting moment for both the Solander and the Arluk III reaches a maximum and their stiffness becomes zero. This means that if the heeling force that caused either boat to reach that angle continues and Fred just sits there. then the boat will continue to tip until it capsizes. On the other hand, the Mariner XL still has 72.5% of its initial stiffness and it will take another 7 or 29.2% more inclination before its righting moment reaches a maximum and its stiffness becomes zero.

As we follow the curves over the hump, the indicated stiffness of all boats becomes negative. which means a decrease in righting moment as the angle of inclination increases, but though the righting moment diminishes it still has a positive value until it reaches zero where the curve cuts the horizontal axis. This means that at any point on the downward slope a heeling force slightly greater than the righting moment will capsize the boat but, should the heeling force also diminish to a value slightly less than the righting moment, the boat will immediately return over the hump to a new and stable balance point coincident with the diminished heeling force. As the opposing forces cannot be balanced on the downward slope, this must be considered an unstable region. The shape of the hump itself has some correlation to the characteristics of the kayak. A smooth rounded hump indicates a gradual transition into the unstable region, generally giving the paddler more time to react if the heel is accidental, and smoother, more predictable control if the boat is being leaned deliberately, than is the case for a more defined peak which indicates a more sudden transition into unstable regions and more difficult control around the peak

As the feeling of tippiness or responsiveness is largely influenced by the initial stability characteristics of a boat, the paddlers who felt the Arluk III to be more stable than the Solander are supported by the shape of the Solander's stability curve and its indication of initial tenderness. Comparison of the Mariner XL and Arluk III curves indicates that up to around I5o of inclination both boats will respond similarly to a lean or a heeling force, but the Mariner XL may be leaned much further before reaching unstable regions. and 35% further before the righting moment becomes zero in its case.

Stability curve analysis -- Xlrvsbl3.gif (2985 bytes)

SLOPES REPRESENTED IN THESE ILLUSTRATIONS ARE TANGENTIAL TO THE CURVES AT THE ANGLES OF INCLINATION INDICATED. THE BASE IS UNITY (1 ) AND THE HEIGHT OF EACH TRIANGLE IS MEASURED USING THE SAME PROPORTIONS AS IF THE SCALE OF THE HORIZONTAL AND VERTICAL AXES OF THE CURVE. UNITS ARE LBS. VERTICALLY AND DEGREES HORIZONTALLY.

Box 1 shows the three tangents taken from all three curves at the point of origin, enabling the following comparisons to be made:

Righting Moment

Stiffness

Mariner XL 0 lbs.ft 0.69 lbs.ft/degree
Arluk III 0 lbs.ft 0.67 lbs.ft/degree
Solander 0 lbs.ft 0.48 lbs.ft/degree

And from Box 2. with tangents taken from the curves at an angle of inclination of 8 :

Righting Moment Stiffness
Mariner XL 6.0 lbs.ft 0.68 lbs.ft/degree
Arluk III 5.8 lbs.ft 0.67 lbs.ft/degree
Solander 5.8 lbs.ft 0.89 lbs.ft/degree

Box 3, with tangents taken from the curves at an angle of inclination of 24 .

Righting Moment Stiffness
Mariner XL 16.3 lbs.ft 0.5 lbs.ft/degree
Arluk III 13.0 lbs.ft 0     lbs.ft/degree
Solander 13.4 lbs.ft 0     lbs.ft/degree