Review of Alubat 58

The hull is made of aluminium. Aluminum is strong and forgiving. Where an impact on a fiberglass hull will result in major gelcoat damage and possible cracking, an aluminum hull will probably only have a scratch or a small bend. The only concern is electrolysis. Ensure that you have proper sacrificial anodes installed. Finally, aluminium is not prone to osmosis.

The boat is equipped with 7 berths, a galley, 600 liters (158 US gallons, 131 imperial gallons) fresh water capacity, toilet facility and 200 liters (52 US gallons, 43 imperial gallons) waste water capacity.

The interior is like most other boats made of teak. Teak has the advantage of being naturally very oily and therefore water-repellent, which is suitable on boats.

The Alubat 58 is built with a ketch rig. A ketch rig is generally considered easier to handle, because the sails are smaller, and because it can sail on most points to the wind with one sail completely taken down for repair or while reefing. The sail configuration of a ketch allows for better comfort and stability when sailing downwind or on a broad reach.

The Alubat 58 has been built with different keel alternatives.

Fin keel

One option is 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 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 additional surface area created by the cast iron keel in comparison to a lead keel of the same weight would be negligible for cruising yachts.

The boat can only enter major marinas as the draft is about 2.40 - 2.50 meter (7.87 - 8.17 ft) dependent on the load. See immersion rate below.

Fin keel

Another option is a fin 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.

Alubat 58 can enter even shallow marinas as the draft is just about 1.35 - 1.45 meter (4.43 - 4.73 ft) dependent on the load. See immersion rate below.

The fuel tank has a capacity of 1000 liters (264 US gallons, 219 imperial gallons).

The boat may be equipped with an inboard Yanmar 4LHA-HTA diesel engine at 160 hp (119 kW). Calculated max speed is about 9.2 knots

What is Capsize Screening Formula (CSF)?

The capsize screening value for Alubat 58 is 1.77, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

Alubat 58 holds a 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 9.8 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.

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Alubat 58 is about 554 kg/cm, alternatively 3102 lbs/inch.
Meaning: if you load 554 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 3102 lbs cargo on the boat it will sink 1 inch.

What is L/B (Length Beam Ratio)?

The l/b ratio for Alubat 58 is 3.39.

Compared with other similar sailboats it is more spacy than 79% of all other designs. It seems that the designer has chosen a significantly more spacy hull design.

What is a Ballast Ratio?

The ballast ratio for Alubat 58 is 36%.

This ballast ratio is higher than 54% of all similar sailboat designs. Since the ballast ratio and the righting moment (i.e. better ability to resist heeling) is strongly correlated, a ballast ratio just above average indicates an ability to resist heeling above average.

What is Displacement Length Ratio?

The DL-ratio for Alubat 58 is 165 which categorizes this boat among 'light racers'.

73% 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 91m² (979 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 Alubat 58 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.