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The Rosborough boats make a long journey to reach us; all the way from Halifax, Nova Scotia to Whidbey Island, Washington. What possess us to do such a thing? The boat. Simply put, there's nothing like it that's built on the West Coast. And the boat is ideally suited to the U.S. west coast, and the Pacific Northwest. So in the end, it's worth the trouble and expense.

Most of our Rosborough customers fit into the rather large Baby Boomer generation (us too!). As such what most are looking for is a safe and comfortable trailerable cruiser. What our customers are not looking for is a boat that requires high speeds in order to operate properly and efficiently; namely a deep-v hull. It's a time in the lives of most of our customers when they look forward to taking it easy while cruising at moderate speeds. Many are former sailors and are moving to a power cruiser to get out of the weather, to lessen the work load while cruising, and to have a trailerable boat. Almost everyone is interested in slowing down a bit to enjoy the scenery, to enjoy the trip and just being on the boat rather than only the destination, and to do it at a pace that yields fairly good fuel economy and comfort. Sailors are already used to a slower pace and low fuel bills and those folks that currently have powerboats also look forward to the attributes of the RF-246 hull (slower speed ability and better fuel economy).

What really makes the RF-246 shine is its versatility. Very few boats are able to successfully perform in all the ways a Rosborough RF-246 does. Given that every boat is made up of several (often conflicting) compromises the RF-246 is unique in its ability to blend all its compromises into a whole that's greater than the sum of the parts. Speed is dictated by weather (water conditions) and/or desired fuel burn and not by a restrictive hull design. The RF-246 operator is literally able to choose a speed from in-gear idle to over 30 knots (dependent on power) and everything in between. However, we feel strongly that if you just concentrate on higher speeds you're missing the best part of the Rosborough hull design. We prefer to think of the higher speeds as "in reserve" speed for those times when it makes sense to run at higher speeds. The hull really does its best between 9 and 12 knots. Certainly one can slow down even more and the RF-246 does really well even at displacements speeds though something around 7 knots is more comfortable (depending on water conditions). And it doesn't affect the mileage a lot to push up to the 15 knot range (again, depending on power chosen) but once above 15 knots you're definitely trading fuel for speed in an escalating manner.

At 12 to 15 knot the RF-246 will eat up the miles in comfort and return good economy. Few folks seem to stay underway continuously at cruise speeds for more than 4 to 6 hours, at 12 knots that 48 to 72 miles toward the next destination, and at 15 knots 60 to 90 miles. My favorite speed is about 9 knots for an excellent fuel burn, a very comfortable ride, and a very respectable 40 to 50 miles of travel in our 4 to 6 hour window.

What can you expect for economy? First understand that we're striving to give you "real world" information, and also understand that winds, and currents, and adverse water conditions make a big difference...sometimes a really big difference. With that in mind what we typically see is 2.25 at 15 knots, 2.4 at 12 knots, and getting close to 3 nmpg at 8 to 9 knots. Those are good numbers for an 8,000 pound 25-foot boat. By compariosn my own personal Tolly 26 which is 10' wide and 9,000 pounds gets 1.6 nmpg at 15 knots! Also, don't confuse these numbers with statute miles per gallon which is what lot of boat tests and manufacturers use since the sound better. But nautical charts are in nautical miles and what you measure and then divide by speed for time in route as such; nautical miles per gallon is really the proper way to present the information or you'll end up using more fuel that you think if you're making a 100 nautical miles leg (which is 115 statute miles).

Unless you're building a radical hull design with exotic materials (read...expensive) there are really only two ways to get better fuel economy out of a planing hull; either make it lighter or slow it down. If you go too far with the "make it lighter" scheme it gets uncomfortable (based on waterplane area versus weight (what's called the Heave Factor) it just flat gets "corky") and the hull is less able to carry the weight of lots of liquids and cruising stores. IRealistically then, for a true cruiser, the best alternative is to just slow down (but only if the hull can do it). That's what so-called trawlers or trollers do but then they're restricted to displacement speeds (6.7 knots for a RF-246 sized boat) and don't have the option of powering up to deal with getting through a pass or perhaps getting in before dark; or getting across an open section first thing in the morning when the wind is down and the seas calm.

A semi-displacement hull like the RF-246 seeks to take advantage of slower speeds for better fuel economy but at a pace that will cover some miles for working or cruising. A semi-displacement hull also runs in a speed range that will keep the crew more comfortable in adverse water conditions. It's able to handle the higher weights that a cruising boat usually carries in liquid loads, stores, and personal gear. And it keeps some speed in reserve for times when it's actually needed (rather than having to operate there due to design).

So why not a semi-displacement hull for everything? Well, it still can't carry the loads that a true displacement cruiser can for very long distances if that's the goal, and it can't run with a deep-v hull in rough conditions. Sort of like a minivan isn't going to keep up with a sports car in the mountains. Deep-v hulled boats are sport boats intended to run relatively short distances at high speeds (originally they were patrol boats and offshore racing boats), and are hard on their crews and equipment if used for long periods of time. Most folks (but not all) don't find them very comfortable for laid back longer distance cruising just as many wouldn't find something like a Porsche Boxster the ideal traveling car.

As always, you have to find the hull type and boat style that most fits what you want to do with your boat. I can tell you why I think the Rosborough RF-246 is such a nice choice (including its subperb construction) but if it doesn't do what you want to do with a boat it's just not a good choice.