Review of Esse 850

Both the hull and the deck is made of fibreglass. A hull made of 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 boat is equipped with 2 berths.

The Esse 850 is built with a fractional rig. The sail area for the mailsail + jib is 34.9 m² (375.1 ft²). 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 gennaker or a spinnaker for optimal speed.

Drop keel

The Esse 850 is built with a drop keel. A drop keel is a lifting keel that can be lowered and raised vertically, allowing the boat to enter shallow waters.

The boat can enter most marinas as the draft is just about 1.50 - 1.60 meter (4.92 - 5.22 ft) dependent on the load. See immersion rate below.

What is Capsize Screening Formula (CSF)?

The capsize screening value for Esse 850 is 2.06, 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 6.8 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 Esse 850 is about 114 kg/cm, alternatively 643 lbs/inch.
Meaning: if you load 114 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 643 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Esse 850 is 10.9 - 11.6.

Comparing this ratio with similar sailboats show that it is more comfortable than 7% 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 Esse 850 is 3.86.

Compared with other similar sailboats it is slimmer than 99% 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 Esse 850 is 56%.

This ballast ratio is higher than 98% 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 significantly above average indicates a very high ability to resist heeling.

What is Displacement Length Ratio?

The DL-ratio for Esse 850 is 71 which categorizes this boat among 'ultra light racers'.

98% of all similar sailboat designs are categorized as heavier. A light displacement requires less sailarea and has higher accellerations.

What is SA/D (Sail Area Displacement ratio)?

The SA/D for Esse 850 with ISO 8666 reference sail is 30.6, with a 135% genua the SA/D is 35.4.

The SA/D ratio indicates that it is faster than 100% of all similar sailboat designs in light wind.

The Esse 850 has more rig than 97% of all similar sailboats, which indicates that the boat is significantly overrigged.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 25m² (269 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.

Dimensions of sail for fractional rig.

Are your sails worn out? You might find your next sail here: Sails for Sale

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.

Keels with moving parts need to be inspected and maintained on a regular basis according to advice given in owner's manual. Manufacturers usually advise which maintenance work can be done by the owner and which work should be carried out by a suitably experienced boatyard.

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 Esse 850 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.