Review of Dehler 34 (2016)

Both the hull and the deck is made of fibreglass. Generally, a hull made of fibreglass requires only a minimum of maintenance during the sailing season.
The hull is a double hull 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 deck is a double deck which improves the indoor climate.

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 genaker or a spinnaker for optimal speed.

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.

The boat can only enter major marinas as the draft is about 1.95 - 2.05 meter (6.40 - 6.70 ft) dependent on the load. See immersion rate below.

Dehler 34 (2016) is typically equipped with an inboard Volvo Penta D1-30 diesel engine at 27.0 hp (20 kW), which gives a max speed about 6.0 knots.

The transmission is a saildrive.

The fuel tank has a capacity of 160.0 liters (42 US gallons, 35 imperial gallons).

What is Capsize Screening Formula (CSF)?

The capsize screening value for Dehler 34 (2016) is 2.00, indicating that this boat could - if evaluated by this formula alone - be accepted to participate in ocean races.

Dehler 34 (2016) holds one CE certification:

The boat is by European Union certified as Class A. OCEAN:

What is Theoretical Maximum Hull Speed?

The theoretical maximal speed of a displacement boat of this length is 7.5 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 Dehler 34 (2016) is about 231 kg/cm, alternatively 1296 lbs/inch.
Meaning: if you load 231 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 1296 lbs cargo on the boat it will sink 1 inch.

What is Motion Comfort Ratio (MCR)?

The Motion Comfort Ratio for Dehler 34 (2016) is 23.5.

Comparing this ratio with similar sailboats show that it is more comfortable than 38% of all similar sailboat designs. This comfort value is just below average.

What is L/B (Length Beam Ratio)?

The l/b ratio for Dehler 34 (2016) is 2.86.

Compared with other similar sailboats it is more spacy than 82% of all other designs. It seems that the designer has chosen a significantly more spacy hull design.

What is a Ballast Ratio?

The ballast ratio for Dehler 34 (2016) is 35%.

This ballast ratio shows a righting moment that is higher than 24% of all similar sailboat designs. A righting moment (ability to resist heeling) significantly below average.

What is Displacement Length Ratio?

The DL-ratio for Dehler 34 (2016) is 189 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.

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

The SA/D for Dehler 34 (2016) with ISO 8666 reference sail is 18.2, with a 135% genua the SA/D is 21.0.

The SA/D ratio indicates that it is faster than 69% of all similar sailboat designs in light wind.

The Dehler 34 (2016) has more rig than 69% of all similar sailboats, which indicates that the boat is slightly overrigged.

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 40m² (430 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.

This section shown boat owner's changes, improvements, etc. Here you might find inspiration for your boat.

Do you have changes/improvements you would like to share? Upload a photo and describe what to look for.

We are always looking for new photos. If you can contribute with photos for Dehler 34 (J/V) 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.