Review of Oceanis 51.1

The boat is equipped with 400.0 liter fresh water capacity.

The Oceanis 51.1 is 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 gennaker or a spinnaker for optimal speed.

The Oceanis 51.1 has been built with different keel alternatives.

Shallow keel

One option is a shallow keel. A shallow keel allow to sail both coastal and inland waters.

The keel is made of iron. Many people prefer lead keel in favour of iron. The main argument is that lead is much heavier than iron and a lead keel can therefore be made smaller which again result in less wet surface, i.e. less drag. In fact iron is quite heavy, just 30% less heavy than lead, so the advantage of a lead keel is often overstated. As the surface of a fin type keel is just a fraction of the total wet surface, the difference between an iron keel and a lead keel can in reality be ignored for cruising yachts.

The boat can only enter major marinas as the draft is about 1.85 - 1.95 meter (6.07 - 6.37 ft) dependent on the load. See immersion rate below.

Fin keel

Another option is a fin keel. A boat with a fin keel is more manoeuvrable but has less directional stability than a similar boat with a full keel.

This keel is also made of iron.

Oceanis 51.1 can only enter major marinas as the draft is about 2.30 - 2.40 meter (7.55 - 7.85 ft) dependent on the load. See immersion rate below.

Deep keel

Another option is a deep keel. A deep keel provide a better healing moment than a shallow keel.

The boat can only enter major marinas as the draft is about 2.80 - 2.90 meter (9.19 - 9.49 ft) dependent on the load. See immersion rate below.

The boat may be equipped with an inboard engine at 80 hp (59 kW). Calculated max speed is about 8.3 knots

The fuel tank has a capacity of 200.0 liters (52 US gallons, 43 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Oceanis 51.1 is 2.01, indicating that this boat would not be accepted to participate in ocean races.

Oceanis 51.1 holds three CE certifications:

If less than 13 in on board the boat is by European Union certified as Class A. OCEAN:
If less than 14 in on board the boat is by European Union certified as Class B. OFFSHORE:
If less than 16 in on board the boat is by European Union certified as Class C. INSHORE:

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 9.2 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.

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Oceanis 51.1 is about 466 kg/cm, alternatively 2614 lbs/inch.
Meaning: if you load 466 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 2614 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Oceanis 51.1 is 24.9.

Comparing this ratio with similar sailboats show that it is more comfortable than 15% of all similar sailboat designs. This is a comfort value significantly below average.

What is L/B (Length Beam Ratio)?

The l/b ratio for Oceanis 51.1 is 3.12.

Compared with other similar sailboats it is more spacy than 88% of all other designs. It seems that the designer has chosen a significantly more spacy hull design.

What is Displacement Length Ratio?

The DL-ratio for Oceanis 51.1 is 126 which categorizes this boat among 'ultra light racers'.

88% of all similar sailboat designs are categorized as heavier. A light displacement requires less sailarea and has higher accellerations.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 72m² (775 ft²).
Based on this, your favourite maritime shop can tell you the quantity you need.

Note: If you use a paint roller you will need more paint than if you use a paintbrush.

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 is reserved boat owner's modifications, 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.

We are always looking for new photos. If you can contribute with photos for Oceanis 51.1 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.