Review of Neptun 27

The hull is made of fibreglass. Generally, a hull made of 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 boat is equipped with 5 berths.

The Neptun 27 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.

The Neptun 27 has been built with different keel alternatives.

Fin keel

The Neptun 27 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 enter even shallow marinas as the draft is just about 1.25 - 1.35 meter (4.10 - 4.40 ft) dependent on the load. See immersion rate below.

DaggerBoard aka Sword

The Neptun 27 is equipped with a daggerboard keel. A daggerboard is a lifting keel that can be lowered and raised, allowing the boat to enter shallow waters as well.

Neptun 27 can enter even shallow marinas as the draft is just about 0.65 - 0.75 meter (2.13 - 2.43 ft) dependent on the load. See immersion rate below.

The Neptun 27 has been equipped with different engine alternatives.

Alternative 1:

An outboard motor is often used on this boat. In that case the boat will typically require a power of 3 - 4 hp, alternatively 75 - 90 lbs thrust if you prefer an electrical motor. Electric outboards are becoming popular for sailboat owners who want clean instant power with less noise and no exhaust fumes.

Alternative 2:

The boat may be equipped with an inboard engine

What is Capsize Screening Formula (CSF)?

The capsize screening value for Neptun 27 is 2.11, indicating that this boat would not 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 6.5 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 Neptun 27 is about 119 kg/cm, alternatively 670 lbs/inch.
Meaning: if you load 119 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 670 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Neptun 27 is 14.1.

Comparing this ratio with similar sailboats show that it is more comfortable than 14% 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 Neptun 27 is 3.38.

Compared with other similar sailboats it is slimmer than 85% of all other designs. It seems that the designer has chosen a significantly more speedy hull design.

What is a Ballast Ratio?

The ballast ratio for Neptun 27 is 33%.

This ballast ratio shows a righting moment that is higher than 18% of all similar sailboat designs. A righting moment (ability to resist heeling) significantly below average.

What is Displacement Length Ratio?

The DL-ratio for Neptun 27 is 129 which categorizes this boat among 'ultra light racers'.

92% 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 20m² (215 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 Neptun 27 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.