Review of OVNI 31

Basic specs.

The OVNI 31 is a sailboat designed by the French maritime architect Philippe Briand in the mid seventies. The OVNI 31 is built by the French yard Alubat.

Here we would have liked to show you nice photos of the OVNI 31.
If you have a photo you would like to share: Upload Image

Looking for a new boat? Find a OVNI 31 or similar boat for sale

Hull

The hull is made of aluminium.

Rig

The boat equipped with a masthead rig. The advantage of a masthead rig is its simplicity and the fact that a given sail area - compared with a fractional rig - can be carried lower and thus with less heeling moment.

Sailing characteristics

This section covers widely used rules of thumb to describe the sailing characteristics. Please note that even though the calculations are correct, the interpretation of the results might not be valid for extreme boats.

Theoretical Maximum Hull Speed

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 6.8 knots. The term "Theoretical Maximum Hull Speed" is widely used even though a boat can sail faster. The term shall be interpreted as above the theoretical speed a great additional power is necessary for a small gain in speed.

Immersion rate

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for OVNI 31 is about 171 kg/cm, alternatively 959 lbs/inch.
Meaning: if you load 171 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 959 lbs cargo on the boat it will sink 1 inch.

Sailing statistics

This section is statistical comparison with similar boats of the same category. The basis of the following statistical computations is our unique database with more than 26,000 different boat types and 350,000 data points.

L/B (Length Beam Ratio)

What is L/B (Length Beam Ratio)?

The l/b ratio for OVNI 31 is 2.90.

Compared with other similar sailboats it is more spacy than 73% of all other designs. It seems that the designer has chosen a slightly more spacy hull design.

Maintenance

Rig

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.

**Guiding dimensions of running rig**
Usage	Length		Diameter
Jib sheet	9.5 m	(31.2 feet)	12 mm	(1/2 inch)
Genoa sheet	9.5 m	(31.2 feet)	12 mm	(1/2 inch)
Mainsheet	23.8 m	(77.9 feet)	12 mm	(1/2 inch)
Spinnaker sheet	20.9 m	(68.6 feet)	12 mm	(1/2 inch)

Boat owner's ideas

This section is reserved boat owner's changes, improvements, etc. Here you might find (or contribute with) inspiration for your boat.

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

Finally

We are always looking for new photos. If you can contribute with photos for OVNI 31 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.

References

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