Review of Hallberg-Rassy 31 Mk II

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. And outside the sailing season, just bottom cleaning and perhaps anti-fouling painting once a year - a few hours of work, that's all.

The interior is like most other boats made of teak.
The boat is equipped with 3 cabins, 6 berths, a galley and toilet facility.

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 Hallberg-Rassy 31 Mk II is equipped with a fin keel. The fin keel is the most common keel and provides splendid manoeuvrability. The downside is that it has less directional stability than a long 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 enter most marinas as the draft is just about 1.71 - 1.81 meter (5.61 - 5.91 ft) dependent on the load. See immersion rate below.

Hallberg-Rassy 31 Mk II is typically equipped with an inboard Volvo Penta D1-20 diesel engine at 19.0 hp (14 kW).

The fuel tank has a capacity of 60.0 liters (15 US gallons, 13 imperial gallons).

Hallberg-Rassy 31 Mk II holds one CE certification:

The boat is by European Union certified as Class A. OCEAN:

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.0 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 Hallberg-Rassy 31 Mk II is about 182 kg/cm, alternatively 1022 lbs/inch.
Meaning: if you load 182 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1022 lbs cargo on the boat it will sink 1 inch.

What is L/B (Length Beam Ratio)?

The l/b ratio for Hallberg-Rassy 31 Mk II is 2.92.

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.

What is a Ballast Ratio?

The ballast ratio for Hallberg-Rassy 31 Mk II is 44%.

This ballast ratio shows a righting moment that is higher than 66% of all similar sailboat designs. A righting moment (ability to resist heeling) just above average.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 31m² (333 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 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 Hallberg-Rassy 31 Mk II 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.