Review of Tetis

The boat equipped with a fractional rig. A fractional rig has smaller headsails which make tacking easier, which is an advantage for cruisers and racers, of course. The downside is that having the wind from behind often requires a genaker or a spinnaker for optimal speed.

The keel is made of lead. Compared with iron, lead has the advantage of being 44% heavier, which allows a smaller keel and hence less water resistance and higher speed.

The boat can enter even shallow marinas as the draft is just about 1.35 - 1.45 meter (4.43 - 4.73 ft) dependent on the load. See immersion rate below.

What is Capsize Screening Formula (CSF)?

The capsize screening value for Tetis is 1.77, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Tetis is about 147 kg/cm, alternatively 825 lbs/inch.
Meaning: if you load 147 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 825 lbs cargo on the boat it will sink 1 inch.

What is L/B (Length Beam Ratio)?

The l/b ratio for Tetis is 3.52.

Compared with other similar sailboats it is slimmer than 90% of all other designs. It seems that the designer has chosen a significantly more speedy hull design. This type of design is also referred to as 'needle'.

What is a Ballast Ratio?

The ballast ratio for Tetis is 44%.

This ballast ratio shows a righting moment that is higher than 69% of all similar sailboat designs. A righting moment (ability to resist heeling) just above average.

What is SA/D (Sail Area Displacement ratio)?

The SA/D for Tetis with ISO 8666 reference sail is 15.7, with a 135% genua the SA/D is 18.6.

The SA/D ratio indicates that it is faster than 46% of all similar sailboat designs in light wind.

The Tetis has more rig than 76% of all similar sailboats, which indicates that the boat is significantly overrigged.

What is Relative Speed Performance?

The Relative Speed Performance for Tetis is 21

The relative speed performance is 21 which means that a it is faster than 21% of all similar sailboat designs.

Dimensions of sail for fractional rig.

Are your sails worn out? You might find your next sail here: Sails for Sale

If you need to renew parts of your running rig and is not quite sure of the dimensions, you may find the estimates computed below useful.

This section shown boat owner's changes, improvements, etc. Here you might find inspiration for your boat.

Do you have changes/improvements you would like to share? Upload a photo and describe what to look for.

We are always looking for new photos. If you can contribute with photos for Tetis it would be a great help.

If you have any comments to the review, improvement suggestions, or the like, feel free to contact us. Criticism helps us to improve.

[Ref 1]: ISO 8666 Small craft — Principal data.
[Ref 3]: ISO 12215-5 Small craft — Hull construction and scantlings.