crash test dehler 31 yacht

Privacy Guaranteed - your email is never shared with anyone, opt out any time.

Review of Dehler 31

Basic specs..

The hull is made of hand laid fibreglass. Generally, a hull made of hand laid 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 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 boat is equipped with 3 cabins and 6 berths.

The boat 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 genaker or a spinnaker for optimal speed.

The Dehler 31 has been built with different keel alternatives.

One option is a deep keel. A deep keel provide a better healing moment than a shallow 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 difference between an iron keel and a lead keel can in reality be ignored for cruising yachts.

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.

Another option is a fin keel. The fin keel is the most common keel and provides splendid manoeuvrability. The downside is that it has less directional stability than a long keel.

This keel is also made of iron.

Dehler 31 can enter even shallow marinas as the draft is just about 1.45 - 1.55 meter (4.76 - 5.06 ft) dependent on the load. See immersion rate below.

The boat is typically equipped with an inboard Yanmar diesel engine at 9 hp (6 kW). Calculated max speed is about 4.1 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.

What is Capsize Screening Formula (CSF)?

The capsize screening value for Dehler 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 6.9 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 31 is about 165 kg/cm, alternatively 926 lbs/inch. Meaning: if you load 165 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 926 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)?

What is L/B (Length Beam Ratio)?

What is a Ballast Ratio?

What is Displacement Length Ratio?

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

What is Relative Speed Performance?

Maintenance

When buying anti-fouling bottom paint, it's nice to know how much to buy. The surface of the wet bottom is about 28m 2 (301 ft 2 ). Based on this, your favourite maritime shop can tell you the quantity you need.

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 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 Dehler 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.

Great choice! Your favorites are temporarily saved for this session. Sign in to save them permanently, access them on any device, and receive relevant alerts.

• Sailboat Guide

Dehler 31 is a 30 ′ 10 ″ / 9.4 m monohull sailboat designed by E. G. Van de Stadt and built by Dehler Yachts between 1984 and 1994.

Rig and Sails

Auxilary power, accomodations, calculations.

The theoretical maximum speed that a displacement hull can move efficiently through the water is determined by it's waterline length and displacement. It may be unable to reach this speed if the boat is underpowered or heavily loaded, though it may exceed this speed given enough power. Read more.

Classic hull speed formula:

Hull Speed = 1.34 x √LWL

Max Speed/Length ratio = 8.26 ÷ Displacement/Length ratio .311 Hull Speed = Max Speed/Length ratio x √LWL

Sail Area / Displacement Ratio

A measure of the power of the sails relative to the weight of the boat. The higher the number, the higher the performance, but the harder the boat will be to handle. This ratio is a "non-dimensional" value that facilitates comparisons between boats of different types and sizes. Read more.

SA/D = SA ÷ (D ÷ 64) 2/3

• SA : Sail area in square feet, derived by adding the mainsail area to 100% of the foretriangle area (the lateral area above the deck between the mast and the forestay).
• D : Displacement in pounds.

Ballast / Displacement Ratio

A measure of the stability of a boat's hull that suggests how well a monohull will stand up to its sails. The ballast displacement ratio indicates how much of the weight of a boat is placed for maximum stability against capsizing and is an indicator of stiffness and resistance to capsize.

Ballast / Displacement * 100

Displacement / Length Ratio

A measure of the weight of the boat relative to it's length at the waterline. The higher a boat’s D/L ratio, the more easily it will carry a load and the more comfortable its motion will be. The lower a boat's ratio is, the less power it takes to drive the boat to its nominal hull speed or beyond. Read more.

D/L = (D ÷ 2240) ÷ (0.01 x LWL)³

• D: Displacement of the boat in pounds.
• LWL: Waterline length in feet

Comfort Ratio

This ratio assess how quickly and abruptly a boat’s hull reacts to waves in a significant seaway, these being the elements of a boat’s motion most likely to cause seasickness. Read more.

Comfort ratio = D ÷ (.65 x (.7 LWL + .3 LOA) x Beam 1.33 )

• D: Displacement of the boat in pounds
• LOA: Length overall in feet
• Beam: Width of boat at the widest point in feet

Capsize Screening Formula

This formula attempts to indicate whether a given boat might be too wide and light to readily right itself after being overturned in extreme conditions. Read more.

CSV = Beam ÷ ³√(D / 64)

VDS #392. Also called DEHLER 32, DUETTA 94. Shallow draft: 3.6’/1.1m

Embed this page on your own website by copying and pasting this code.

• About Sailboat Guide

©2024 Sea Time Tech, LLC

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Yachting World

• Digital Edition

Dehler 30 yacht test: This one-design racer has a real double appeal

• Matthew Sheahan
• May 20, 2020

An award-winning offshore blaster, the Dehler 30 is many things to many sailors. But can a short-handed one-design racer-cruiser really tick so many boxes?

Product Overview

Manufacturer:, price as reviewed:.

Talk to those who have switched to short-handed offshore racing and you’ll be hard pressed to find many who want to go back to a weather rail stacked with crew. It’s not that they’ve suddenly realised that they don’t like sharing the experience with others, or that the boat just feels cluttered below, but that it is just more satisfying sailing two-up . Plus, it’s often a lot cheaper. It’s these two factors above all that surely explain the increase in popularity in this kind of sailing.

Yet, unlike the moment when we realised that planing sportsboats were a lot more fun than the tubby lead mines of the day that rolled downwind like metronomes, or the sudden realisation that gybing an asymmetric spinnaker was no harder than tacking a jib, the growth in short-handed offshore sailing has been more gradual. And it is also building from another corner of the sport as the momentum for the new Olympic offshore class in 2024 gathers pace.

As the plans for Paris 2024 are now starting to take shape, where mixed gender entries will be a requirement, there is also a feeling that there will be opportunities for a wider range of age, experience and crew weights. This has triggered a fair bit of interest among a broader group of sailors than normal. It has also drawn the attention of some of the world’s top builders as they look into producing boats that might tap into this new scene.

Perfect for two but with the capability for more, this is a comprehensively kitted out 30-footer that’s easy to handle. Photo: Hanse Yachts AG

Of course some, like Beneteau, have been in this space for a while with their Figaro range of offshore racers. Jeanneau has also been successful most recently with its SunFast 3200 and 3600 models, with the new Sun Fast 3300 starting to make an impression as well. Other builders like JPK, J/Boats and Pogo have also been successful in developing interesting boats in this area. And now one of the latest to step into the ring is Dehler.

Well known for its innovative approach to design along with a racing heritage that stretches back to the 1980s when boats like the DB1 put it on the map, the German production builder has launched a 30ft offshore pocket rocket that appears to be aimed straight at the short-handed world. It is a boat that ignores handicap rules like IRC and focuses instead on creating a strict, high performance, offshore one-design.

But let’s get one thing out into the open from the start: this is a boat with an identity crisis. Look at the pictures and study the detailed deck layout and spec and it is easy to see that this is a well thought out, comprehensively equipped racer. Yet study the interior layout and overall style and the message is that while it’s a modern, quick 30-footer, it’s also designed to be a sprightly family cruiser. So can it really be both?

Article continues below…

Ràn VII: On board the Stealth Bomber of the Fast 40+ class

Some boats are the sum of their parts, but Rán VII is really the sum of the parts that aren’t…

Jeanneau Sun Fast 3300 review: The pocket rocket inspired by foiling IMOCAs

Jeanneau’s latest Sun Fast is a whole bundle of fun, as Pip Hare discovered on a full test of the…

When viewed from the outside, the Judel/Vrolijk-designed Dehler looks every bit the racer. The reverse profile bow and the heavily chamfered topsides/gunwale that extend forward from her chainplates give the look of a smaller version of a number of well known racing machines – the Fast 40+ Ran , countless Class 40s , or even the previous Hugo Boss IMOCA 60 spring to mind.

Offshore style

When viewed from dead ahead the rounded, full-sectioned bow and a hard turn of the bilge from slab sided topsides to flat underwater sections are further indications of the modern offshore style. And then there’s the fixed bowsprit off which the Code 0 and A2 and A5 kites are flown. It is removable for cruising, but when it’s in place (as it was for us), it shouts racing.

So too does the carbon mast, the square-topped mainsail and the twin backstays, with tails led forward through rope clutches to the primary winches mounted conveniently for the helmsman and crew. The coarse and fine tune mainsheet systems, along with a mainsheet traveller that runs almost the complete width of the ample beam are also dead giveaways that this boat is set up to race.

It’s clear that a huge amount of thought has gone into the design. In plan, the delta shape sees the maximum beam carried all the way aft to the stern from midships providing the means to generate a high righting moment. The full sections forward where the volume is low down are indications that the distribution of buoyancy is in keeping with modern thinking and contributes to the righting moment using the hull form without creating unnecessary drag through excessive wetted surface area.

It’s likely to be a well-balanced boat when heeled, and the 200kg water ballast tanks on either side add a further boost to righting moment and hence performance. Pump these up using either the gravity or electric feed systems and you have the equivalent of 2-3 people on the rail – people that you don’t have to feed or hot-bunk with.

As it happens, the sporty looks are also in line with the modern cruising style. Beamy sections aft frequently lead to twin rudders, whether you’re racing or cruising. The Dehler 30 is no different, although the linking mechanism between both rudder stocks and the single centreline-mounted tiller is fitted above decks making it very easy to get to. Liferaft stowage is under a lifting section of the aft deck and accessible from the water, whichever way up the boat is: yet another illustration as to how detailed the thinking has been.

Nimble and responsive

Like modern cars that have become bloated with every iteration, today’s boats generally feel bigger than they did a few decades back. Strangely, the Dehler 30 feels smaller. I’m sure half tonners felt bigger than this? The reality is that when compared to other popular brands in this scene such as the Beneteaus, Jeanneaus and JPK’s it is indeed shorter. But the Dehler also feels small in a good way – a boat that feels right for two from the off. It’s a size in which pretty much everything is close to hand without having to let go of the helm.

Short-handed offshore sailors prefer not to depend entirely on their autopilots. Instead, most take the pragmatic view that at some point it will break down and hand steering will become essential. They also believe that at times humans can still sail better than a machine. But aboard the Dehler 30 there is another issue and that is that once you’ve taken the helm, you’re unlikely want to give it back.

Cockpit layout suits single- and double-handed sailing. Photo: Hanse Yachts AG

Light, nimble and responsive, you barely notice that it has twin rudders such is the balance between them. In keeping with modern thinking it’s designed to heel fairly early to a point at which the windward rudder offers minimal drag, which in turn helps to get that single blade feel on the helm.

Manoeuvrability is good under sail, but also under power thanks largely to the fixed three-bladed prop which provides plenty of prop walk… which in turn makes up for the lack of prop wash over the rudders. Overall this is a boat that has been designed to be sailed hands on. Whether you’re steering from the side deck or organising the pit, everything is close to hand, making tacks and gybes as straightforward as they can be.

Our trials started off in a light breeze and in this the Dehler ghosted along nicely before conditions picked up to a modest 10 knots. That was sufficient at least to establish that this is a well-balanced, slippery boat. The modern sailplan gives the first indication of why it performs so well. A high aspect ratio non-overlapping, hanked-on jib that is just 5.5m 2 smaller than the 34.5m 2 square-topped mainsail is the first indication of an ample and sophisticated sailplan.

The furling staysail also makes for a good heavy weather jib for when conditions get punchy upwind. Photo: Hanse Yachts AG

Aside from the provision for a Code 0 and downwind asymmetric kites, the staysail mounted on a detachable inner forestay will be good off the breeze as well as upwind when things have got punchy offshore. The single spreader aft-swept rig is an important part of this with a set of D2s that terminate at the inner forestay mast attachment to give good fore and aft support when you’re hammering upwind under this reduced sail plan.

Less obvious, yet another big contribution to the all round performance, is the 2.20m deep 82kg carbon reinforced fin and 840kg bulb configuration. Aside from generating plenty of righting moment, the deep, parallel-sided fin is efficient when it comes to providing lift, a key reason why it feels like it gets into the groove with ease.

The choice of fin and bulb is interesting as it is unlikely to be treated well under IRC and provides another indication as to how focussed Dehler is on one-design and short-handed sailing. But if it does have a weakness it is the speed with which a snake pit of ropes can build up in the cockpit. And while careful control line management is the answer, the clutter stems largely from an overly sophisticated deck layout and snug cockpit.

The Dehler’s Code 0, with its trendy but practical outrigger, covers a wide range of wind speeds and angles. Photo: Rick Tomlinson

Having got used to what this boat is all about on deck and underway, the big surprise comes when you head below decks where, instead of a Spartan racing interior, the layout is far more modern cruiser. This is where the identity crisis lies.

Creature comforts

Had you simply headed below without looking at the layout on deck you’d likely not be surprised. The trademark Dehler offwhite/grey and red trim also has wood laminate saloon bench seating and a table on the centreline and looks just like you’d expect of a contemporary Dehler.

And with a modest galley to starboard that’ll take a portable fridge, an open plan forepeak, enclosable heads to port and a couple of ‘almost double’ berths aft, it looks like a snug modern production cruiser.

Creature comforts and trademark Dehler trim belie the boat’s racing aspirations. Photo: Rick Tomlinson

The giveaway is the lack of floorboards, which help to achieve a decent 1.82m headroom in an otherwise low freeboard boat. That and the internal water ballast tanks.

But for me the oddest of detail was the fabric hull liner. While it looks smart on a new boat, it reminded me of boats from another era that didn’t stand the test of time well, and made me question whether a boat of this type really needs it. On that point, Dehler says the creature comforts account for less than 100kg in total and suggest this is a good use of weight when it comes to broadening the use and the appeal of the boat.

But when the boat will be raced primarily by people who like having the sidedeck to themselves for hours on end as they chase down their rivals offshore, I’m not sure that comfort below decks is at the front of their minds.

This boat grew on me quickly because it was so comfortable and rewarding to sail. It just feels like it fits. It’s is easy to handle short-handed and so taps into this growing scene while also appealing to what sportier types may want when they’re family cruising. But sprightly cruising does come at a price. At a base cost of €108,000 excluding VAT and around €160,000 with a full spec and VAT paid it might seem pretty expensive for a 30ft production built, fast family cruiser. Yet come to it from a racing mindset and this is a boat that wants for nothing. With such a comprehensive and high quality specification along with the promise of good one-design racing, it’s an appealing prospect. So can this be both racer and cruiser? The answer is yes, so long as you regard it in this order.

• Forum Listing
• Marketplace
• Advanced Search
• About The Boat
• Boat Review Forum
• SailNet is a forum community dedicated to Sailing enthusiasts. Come join the discussion about sailing, modifications, classifieds, troubleshooting, repairs, reviews, maintenance, and more!

Another crash test...

• Add to quote

Dehler 31 crash test; Crash Test - Dehler 31 yacht - YouTube I would have thought someone had posted this one before but my search came up empty. If it's a re-run, mods feel free to delete!  

Looks real familiar I saw this in continuous looping video running at the dealer booth at Sail Expo about 6 years ago or so. It was filmed / staged to demo the hull strength due a layer of kevlar up forward, IIRC. Fun to watch!  

• ?            
• 176.4K members

Top Contributors this Month

• Yachting Monthly
• Digital edition

Crash Test Boat

• May 4, 2011

What's your worst sailing nightmare?

What’s your worst sailing nightmare? Sinking or capsize? Have you ever run aground on a lee shore?

Yachting Monthly has acquired a second-hand 40ft Jeanneau Sun Fizz 40 ketch, which we will be using over the coming months to test major disaster incidents on board.

Our Crash Test Boat series will be used to test theories about what to do in a disaster scenario.

The aim is to give you the best possible tools to avoid and troubleshoot catastrophe afloat, as well as the confidence to use methods that you know have been tried and ‘Crash Boat tested’. Watch videos from the Crash Test Boat series

2011 programme of controlled sailing disasters

Meet the Crash Test Team

Robert Holbrook: “Why I bought a boat to wreck”

Buy the Crash Test Boat iPad app

Gebrauchtbootkauf : Mehr Modell-Evolution geht nicht – Dehler 31 TOP im Test

Die Dehler 31 ist Teil eines Gebrauchtboot-Vergleichstests:

Für 40.000 lässt sich locker eine optimale Yacht finden. Aber: günstig kaufen und investieren oder lieber alles ausgeben und gleich losfahren? Wir haben fünf Yachten daraufhin getestet:

• Gebrauchtbootkauf: 5 Yachten für unter 40.000 Euro im direkten Vergleich
• Winner 9.50

Modern ist nicht immer besser. Anfang der Neunziger bringt Dehler mit der TOP eine Weiterentwicklung der erfolgreichen Duetta 94, die später Dehler 31 heißt. Die Pinne wird auf Wunsch durch ein Rad ersetzt, und unter Deck beherrschen weiße Oberflächen das Bild. Tiefziehteile aus ABS stehen hoch im Kurs bei Dehler. Sie sind günstig zu fertigen und relativ leicht.

Die verwendet die Werft auf dem Boden und an der Decke, dazu kommen schneeweiße Ober­flächen in Pantry und Navi. Den Salon will man schiffig gemütlich halten und spendiert Mahagoni-Furniere. Das Resultat: ein wilder Mix, der aus heutiger Sicht sehr unruhig wirkt.

Überflüssiges Steuerrad

Auch das Steuerrad ist ein Beispiel der ständigen Veränderungen. Schon einige Jahre alt, läuft die Duetta am Markt gut. Doch die Konkurrenz bietet irgendwann ab 30 Fuß das Lenkrad an. Da muss Dehler mitziehen, um keine Marktanteile zu verlieren. Also wird die Whitlock-Säule als Option angeboten, von einigen Eigner gar nachgerüstet. Das Cockpit ist dafür aber nicht ausgelegt – zu eng, weil alles hinter den Traveller passen muss, und nicht steif genug.

Die Folge: Die Säule wackelt, der Steuermann hat kaum Raum und kommt nur schwer an die Großschot. Dabei fährt die Dehler mit Pinne vorzüglich. Der Platz auf dem Süll ist bequem, und alle erforderlichen Leinen sind in Reichweite.

Die Dehler 31 kann in entsprechender Konfiguration und in gutem Zustand Spaß machen

Hinzu kommt auf dem Testschiff das wie bei allen Probanden ausgeschlagene Ruderlager und ein Autopilot, der dem Steuer jede Feinfühligkeit nimmt. Wie beim Test in YACHT 18/2013 bewiesen, kann sie nämlich durchaus segeln. Als Dehler 32 übrigens ein klein wenig besser, da diese am Heck länger wurde. Dadurch nimmt die Wasserlinie in der Länge zu. Das Resultat ist etwas mehr Speed.

Das war auch nötig, denn innen ist das Schiff schwerer geworden. Die Tür vor der Achterkammer und eine anders gestaltete Navi sorgten für Zusatzgewicht. In der Version mit kurzem Kiel kann die Dehler durchaus Gewicht auf der Kante vertragen, wenn es bei mehr Wind an den Start von Yardstick-Regatten geht.

Die Dehler fährt gutmütig und macht mit Pinne sogar Spaß. Das Decksequipment will nach 30 Jahren endlich in Rente, ebenso wie originale Elektronik. Das kann ins Geld gehen.

Die Dehler 31 TOP im Detail

The most important information about your Dehler

Keep the most important information about your yacht at your fingertips and read it whenever you want!

No documents found

Explore the current Dehler yachts

Customise your dream yacht in seconds!

Seize the moment - schedule your appointment today.