Review of Olsen 42

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.

Fin keel

The Olsen 42 is equipped with 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.

The boat can only enter major marinas as the draft is about 1.95 - 2.05 meter (6.40 - 6.70 ft) dependent on the load. See immersion rate below.

The boat is typically equipped with an inboard Yanmar 4JH2-E diesel engine at 50 hp (37 kW). Calculated max speed is about 7.2 knots

The fuel tank has a capacity of 120.0 liters (31 US gallons, 26 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Olsen 42 is 1.74, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.7 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 Olsen 42 is about 233 kg/cm, alternatively 1307 lbs/inch.
Meaning: if you load 233 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1307 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Olsen 42 is 29.7.

Comparing this ratio with similar sailboats show that it is more comfortable than 46% of all similar sailboat designs. This comfort value is just below average.

What is L/B (Length Beam Ratio)?

The l/b ratio for Olsen 42 is 3.76.

Compared with other similar sailboats it is slimmer than 92% 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 Olsen 42 is 40%.

This ballast ratio shows a righting moment that is higher than 58% of all similar sailboat designs. A righting moment (ability to resist heeling) just above average.

What is Displacement Length Ratio?

The DL-ratio for Olsen 42 is 216 which categorizes this boat among 'light crusers & offshore racers'.

62% 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 41m² (441 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 Olsen 42 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.