Review of Impala 31

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 interior is like many other boats made of mahogany. Mahogany belongs to the hardwood species, known for being water-repellent and resistant to decay. It has an attractive wood grain and holds wood polish and varnish well.
The boat is equipped with 3 cabins, 6 berths, a galley, 120.0 liter fresh water capacity and toilet facility.

The boat has more than one rig.

One option is 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.

Fin keel

The Impala 31 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.

Impala 31 can enter most marinas as the draft is just about 1.60 - 1.70 meter (5.25 - 5.55 ft) dependent on the load. See immersion rate below.

The boat may be equipped with an inboard diesel engine at 10 hp (7 kW). Calculated max speed is about 4.3 knots

The transmission is a saildrive.

The fuel tank has a capacity of 30.0 liters (7 US gallons, 6 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Impala 31 is 2.03, 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 6.6 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 Impala 31 is about 150 kg/cm, alternatively 844 lbs/inch.
Meaning: if you load 150 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 844 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Impala 31 is 18.9 - 20.2.

What is L/B (Length Beam Ratio)?

The l/b ratio for Impala 31 is 3.08.

What is a Ballast Ratio?

The ballast ratio for Impala 31 is 39%.

What is Displacement Length Ratio?

The DL-ratio for Impala 31 is 211 which categorizes this boat among 'light crusers & offshore racers'.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 26m² (279 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 Impala 31 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.