Back to the original question:
Hello I am looking for a bigger/most capable boat( even if my current Alberg 22 is quite capable from my point of view ! ) I have the opportunity to buy a old Pearson Vanguard 33 but it is quite a project a big project and I am looking at a tavana 33 too and at first I did not considered the Tavana but after looking on sailboat data I am quite impressed by the displacement of the boat and kind of interested in the shallow draft options, and the centerboard for more serious sailing ! gives you a nice versatility !
if I understand right you can sail the boat without the centerboard up since there is a longish keel or am I completely wrong and not having the centerboard up would pretty much just be to approach shallow area and motor/ down wind pretty much!?
also wondering if the Tavana 33 as any known offshore passage to his name or if you would considered it for offshore voyaging and if not why !
thank you !
I will start by saying that there is a huge difference between a boat that someone managed to take offshore and make a reasonable passage on, vs. a boat that makes a good offshore cruiser. Whether or not someone successfully made an offshore passage or not, the Tavana would make a very poor choice for offshore cruising.
(This is from comments that I made on an earlier discussion of Tavanas) I don't have time to do a detailed analysis, but as a broad generality a boat that is intended to go offshore should have several key traits; lots of stability, a hull form and rig that can quickly adapt to a broad range of wind speeds and sea states, generous carrying capacity, and robust construction. The Tavana has none of these with the possible exception being robust construction, and even that is also a little questionable.
While I am a big fan of keel/centerboard boats for their flexibility in being able to sail in shallow venues yet potentially offering good performance if well designed, they do require greater care in designing them if they are going to sail well and be seaworthy. It is much harder to obtain enough stability in a keel/centerboard boat than it is in a deeper draft boat since the vertical center of gravity of the ballast is by necessity closer to the vertical center of buoyancy of the boat. The net result is that there are only some mix of three ways to create enough stability in a keel/centerboard boat; 1) Increase form stability (i.e. catboat), 2) add more ballast (typically in the 40 to 55% range) and 3) have a little more draft so that the ballast can be located lower below the boat.
The design of the Tanana does none of these, having minimal form stability, being very short on ballast (around 25%) and having a very minimal draft. Making matters worse this is a very heavy displacement boat on a narrow short waterline resulting in a deep canoe body further lowering the vertical center of buoyancy and reducing stability.
This is a high drag hull form that would require a comparatively large amount of sail area to be able to sail decently in any conditions as compared to a more moderate drag hull form, but the design lacks adequate stability to carry a large enough sail plan for decent light air or safe heavy air sailing. It is also a hull form that is likely to roll and pitch through large angles and snap at the end of the roll for an uncomfortable motion comfort.
The best of the Keel/centerboard cruising boats actually had a shallow fin keel and skeg hung rudders and with the centerboard emerging from the fin keel. This allows the ballast to be located lower and reduces wetted surface and drag. They typically have moderate displacements in the L/D range around 200 to 260 so that the canoe body is not as deep as well.
Stability is required to carry an easy to handle rig that can quickly adapt to changing conditions. In the case of the Tavana, the rig is a low aspect ratio ketch rig, while that keeps the sail plan lower and so helps on a boat with so little inherent stability, it also means a less efficient sail plan that needs much greater sail area than a more efficient sail plan to help the boat sail well. That makes the boat harder to sail and makes it much harder to adapt to a broad range of conditions.
The small water plane of the Tavana would greatly limit the percentage of her overall displacement that could be used for carrying stores, equipment, and consumables.
As a side note, in and of itself displacement does nothing good for a boat. It does not make it more seaworthy, or improve motion comfort. It does not add carrying capacity. It does not make a boat more stable or more robust. It only makes a boat harder to handle, more expensive to build and operate, and perform more poorly.
The robustness issue is harder to explain. Reportedly the Tavana has a very heavy hull layup. But the glass work is crudely done with a larger percentage of non-directional fabric (mat) which does not inherently result in a particularly strong hull, and tends to produce a hull that is more prone to fatigue over time. These boats lack internal framing to help with hull stiffness and reduce fatigue and increase impact resistance. It is my understanding that the early Tavanas had wooden decks and cabins, which can have equal strength to a glass deck and house, but generally do not.
To address your specific case, I would doubt that you can sail the Tavana above a beam reach without the centerboard at least partially down. Without the centerboard down and with such a small effective keel area and inefficient shape, I would expect this boat to make huge amounts of leeway, and roll mercilessly without the damping that the centerboard provides.
Also, for what it worth, as a former Pearson Vanguard owner, the Vanguard would also be a very poor choice for use offshore.