Review of Smaragd

Smaragd anno 1978.

Basic specs.

The Smaragd is a sailboat designed by the Swedish maritime architect L. Sterner in the early seventies. A few hundred boats have been produced. The Smaragd is built by the Swedish yard Rivalbåtar.

Looking for a new boat? Find a Smaragd or similar boat for sale

Interior

Note: the boat has also been sold to be self-made/-interiored, which means that the quality of each boat may vary.

Rig

The Smaragd is 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 gennaker or a spinnaker for optimal speed.

Keel

Unknown keel type

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 1.70 - 1.80 meter (5.58 - 5.88 ft) dependent on the load. See immersion rate below.

Engine

Smaragd may be equipped with an inboard Yanmar diesel engine at 8 hp (5 kW). Calculated max speed is about 4.0 knots

Sailing characteristics

This section covers widely used rules of thumb to describe the sailing characteristics. Please note that even though the calculations are correct, the interpretation of the results might not be valid for extreme boats.

Stability and Safety

What is Capsize Screening Formula (CSF)?

The capsize screening value for Smaragd is 1.51, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

Theoretical Maximum Hull Speed

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.

Immersion rate

The immersion rate is defined as the weight required to sink the boat a certain level. The immersion rate for Smaragd is about 118 kg/cm, alternatively 660 lbs/inch.
Meaning: if you load 118 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 660 lbs cargo on the boat it will sink 1 inch.

Sailing statistics

This section is statistical comparison with similar boats of the same category. The basis of the following statistical computations is our unique database with more than 26,000 different boat types and 350,000 data points.

Motion Comfort Ratio

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Smaragd is 28.0.

Comparing this ratio with similar sailboats show that it is more comfortable than 66% of all similar sailboat designs. This comfort value is just above average.

L/B (Length Beam Ratio)

What is L/B (Length Beam Ratio)?

The l/b ratio for Smaragd is 4.55.

Compared with other similar sailboats it is slimmer than 100% 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'.

Ballast Ratio

What is a Ballast Ratio?

The ballast ratio for Smaragd is 56%.

This ballast ratio shows a righting moment that is higher than 98% of all similar sailboat designs. A righting moment (ability to resist heeling) significantly above average.

D/L (Displacement Length Ratio)

What is Displacement Length Ratio?

The DL-ratio for Smaragd is 186 which categorizes this boat among 'light racers'.

76% of all similar sailboat designs are categorized as heavier. A light displacement requires less sailarea and has higher accellerations.

SA/D (Sail Area Displacement ratio)

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

The SA/D for Smaragd with ISO 8666 reference sail is 17.3, with a 135% genua the SA/D is 19.9.

The SA/D ratio indicates that it is faster than 58% of all similar sailboat designs in light wind.

Over- / underrigged

The Smaragd has more rig than 42% of all similar sailboats, which indicates that the boat is slightly underrigged.

RSP (Relative Speed Performance)

What is Relative Speed Performance?

The Relative Speed Performance for Smaragd is 86

The relative speed performance is 86 which means that a it is faster than 86% of all similar sailboat designs.

Maintenance

Bottom Paint

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 23m² (247 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.

Rig

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.

**Guiding dimensions of running rig**
Usage	Length		Diameter
Mainsail halyard	30.8 m	(101.0 feet)	10 mm	(3/8 inch)
Jib/genoa halyard	30.8 m	(101.0 feet)	10 mm	(3/8 inch)
Spinnaker halyard	30.8 m	(101.0 feet)	10 mm	(3/8 inch)
Jib sheet	10.2 m	(33.3 feet)	12 mm	(1/2 inch)
Genoa sheet	10.2 m	(33.3 feet)	12 mm	(1/2 inch)
Mainsheet	25.4 m	(83.3 feet)	12 mm	(1/2 inch)
Spinnaker sheet	22.3 m	(73.3 feet)	12 mm	(1/2 inch)
Cunningham	3.7 m	(12.1 feet)	10 mm	(3/8 inch)
Kickingstrap	7.4 m	(24.3 feet)	10 mm	(3/8 inch)
Clew-outhaul	7.4 m	(24.3 feet)	10 mm	(3/8 inch)

Boat owner's ideas

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.

Finally

We are always looking for new photos. If you can contribute with photos for Smaragd 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.

References

[Ref 1]: ISO 8666 Small craft — Principal data.
[Ref 3]: ISO 12215-5 Small craft — Hull construction and scantlings.