Review of Olsen 40

Both the hull and the deck is made of hand laid fibreglass. Generally, a hull made of hand laid fibreglass requires only a minimum of maintenance during the sailing season.

Both the hull and the deck is a sandwich construction which improves the indoor climate. Especially when the water is colder than the air in the cabin, then the double hull insulates against cold water and reduce the condense water in the cabin.

The interior is like many other boats made of mahogany. Mahogany belongs to the hardwood species, known for being water-repellent and resistant to decay. It has an attractive wood grain and holds wood polish and varnish well.
The boat is equipped with 3 cabins, 5 berths, a galley, 250.0 liter fresh water capacity and toilet facility.

The Olsen 40 is 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 40 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 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 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.

Olsen 40 may be equipped with an inboard Yanmar 4HJE diesel engine at 44 hp (32 kW). The speed is 8.0 knots.

The transmission is a shaft drive. A shaft drive will in the long run require less maintenance than other types of drive e.g. a sail drive.

The fuel tank, which is made of stainless steel, has a capacity of 140.0 liters (36 US gallons, 30 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Olsen 40 is 1.72, 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 7.5 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 40 is about 225 kg/cm, alternatively 1260 lbs/inch.
Meaning: if you load 225 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1260 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Olsen 40 is 33.3.

What is L/B (Length Beam Ratio)?

The l/b ratio for Olsen 40 is 3.43.

What is a Ballast Ratio?

The ballast ratio for Olsen 40 is 42%.

What is Displacement Length Ratio?

The DL-ratio for Olsen 40 is 270 which categorizes this boat among 'light crusers & offshore racers'.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 39m² (419 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 40 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.