Review of Spacesailer 18
Basic specs.
According to the designer Kim Swarbrick, the S18 was intentionally "overbuilt" with 5/32 wire rope rigging to cope with the constant winds of Perth.
Looking for a new boat? Find a Spacesailer 18 or similar boat for saleBoth the hull and the deck is made of fibreglass. 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 2 berths.
The Spacesailer 18 is built 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.
Fin keel
The Spacesailer 18 is built 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 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 enter even shallow marinas as the draft is just about 1.07 - 1.17 meter (3.51 - 3.81 ft) dependent on the load. See immersion rate below.
An outboard motor is often used on this boat. In that case Spacesailer 18 will typically require a power of 2 - 3 hp, alternatively 33 - 40 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.
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.
What is Capsize Screening Formula (CSF)?
The capsize screening value for Spacesailer 18 is 2.31, 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 5.4 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 Spacesailer 18 is about 68 kg/cm, alternatively 384 lbs/inch.
Meaning: if you load 68 kg cargo on the boat then it will sink 1 cm.
Alternatively, if you load 384 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.
What is Motion Comfort Ratio (MCR)?
The Motion Comfort Ratio for Spacesailer 18 is 11.8.
What is L/B (Length Beam Ratio)?
The l/b ratio for Spacesailer 18 is 2.64.
The ballast ratio for Spacesailer 18 is 31%.
What is Displacement Length Ratio?
The DL-ratio for Spacesailer 18 is 174 which categorizes this boat among 'light racers'.
SA/D (Sail Area Displacement ratio)
Indicates how fast the boat is in light wind:
- Cruising Boats have ratios 10-15
- Cruiser-Racers have ratios 16-20
- Racers have ratios above 20
- High-Performance Racers have ratios above 24
Sail-area/displacement ratio (SA/D ratio): 13.73
Maintenance
When buying anti-fouling bottom paint, it's nice to know how much to buy.
The surface of the wet bottom is about 12m2 (129 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.
| Usage | Length | Diameter | ||
| Jib sheet | 5.5 m | (18.0 feet) | 8 mm | (5/16 inch) |
| Genoa sheet | 5.5 m | (18.0 feet) | 8 mm | (5/16 inch) |
| Mainsheet | 13.7 m | (45.0 feet) | 8 mm | (5/16 inch) |
| Spinnaker sheet | 12.1 m | (39.6 feet) | 8 mm | (5/16 inch) |
This section is reserved boat owner's modifications, improvements, etc. Here you might find (or contribute with) inspiration for your boat.
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