iw 31 sailboat

The Iw 31 is a 30.33ft masthead sloop designed by Sparkman & Stephens and built in fiberglass by IW-Varvet (SWE) between 1968 and 1985.

350 units have been built..

The Iw 31 is a heavy sailboat which is slightly under powered. It is very stable / stiff and has an excellent righting capability if capsized. It is best suited as a coastal cruiser.

Iw 31 for sale elsewhere on the web:

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Review of IW 31

Basic specs..

The boat is typically equipped with an inboard Volvo Penta MD1B diesel engine at 10.0 hp (7 kW), which gives a max speed about 3.9 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 IW 31 is 1.77, indicating that this boat could - if evaluated by this formula alone - 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 6.3 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 IW 31 is about 120 kg/cm, alternatively 676 lbs/inch. Meaning: if you load 120 kg cargo on the boat then it will sink 1 cm. Alternatively, if you load 676 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 Displacement Length Ratio?

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

What is Relative Speed Performance?

Maintenance

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 IW 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.

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Table of Contents

Other iw31's, other notes & links.

Fall 2015, Clan is for sale:

See Clan's list of features.

See the DBA listing for Clan.

http://www.benhall.com/tag/iw-31/

Original sales materials: iw_31_brochure.zip

The giant to-do list is now here.

http://www.dba.dk/31-fods-havkrydser/id-72263946/ http://smhavn.dk/con24.php4 http://iw31.blogspot.com http://www.stormy-iw31.eu/7572/ http://www.stormy-iw31.eu/5881/ http://www.iw31.de/bilder/index.html http://sy-juliette.de/ http://www.halse.de/ http://sparkmanstephens.blogspot.com/2011/02/design-1899-iw-31-class.html http://mermaidscheveningen.webklik.nl/page/ontwerp http://www.iw31-wismar.de/ http://www.iw31.dk/ http://www.iwrig.com/57718625 http://eskapad.wordpress.com/ http://mermaidscheveningen.webklik.nl/page/ontwerp http://www.klassiekepolyesterjachten.nl/page/OverOns http://sailboatdata.com/viewrecord.asp?class_id=5505 http://www.s-and-s-association.org/ http://www.sparkmanstephens.info/doc/5702458zUBmMLGktd9U2RAC4CT7yqTe9.pdf http://www.hinnerk-weiler.de/ http://www.youtube.com/hinnerkWeiler http://www.youtube.com/user/ottorino43 (commented on a video that he owns an IW 31) http://www.youtube.com/user/essen222 (commented on a video that he owns an IW 31) https://picasaweb.google.com/116970321897372292619/IW31Havskum# http://www.faaborg-vaerft.dk/Faaborg_Vaerft_A/S osmosis treatment in DK

http://www.gotakanal.se/sv/Gotakanal/ http://www.skipperguide.de/wiki/Hallands_Väderö

Old Equipment Wish-list/thoughts/suppliers

Odd-ball notes & links

Weather Fax

• mast length is 12.5m

I'm not entirely certain I've put in the correct numbers for all the calculations correctly, but here are our general performance & stability numbers (from sailingcourse.com ):

• The maximum speed of the boat is: 6.29 knots (22ft. at water line)
• The Sail Area Displacement Ratio is: 15.57. The sailboat is a cruiser-racer.
• The Displacement to Length Ratio is: 332.75. The sailboat is a heavy displacement cruiser.
• The Motion Comfort Ratio is: 27.68
• The Stability of the boat is: 1.74 (Stability is predicted !!) (anything less than 2 is considered stable)
• The screening stability value of the boat is: 14.81
• Angle of Vanishing Stability is 193.09 (estimated a 0.7m draft of hull without keel, will try to measure this season) (anything above 120 is good, above 140 is better)
• Ballast Displacement Ratio: %44
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• Boats for sale

Iw 31 for sale

View a wide selection of Iw 31 for sale in your area, explore boats details information, compare prices and find Iw 31 best deals

1976 Sparkman & Stephens Iw 31 for sale

• Sparkman & Stephens

1972 Sparkman and Stephens Iw 31 for sale

• Sparkman and Stephens

1970 Iw 31 Auktion for sale

1970 Iw 31 for sale

1975 Iw 31 for sale

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Iw 31 for sale on DailyBoats.com are listed for a range of prices, valued from $10,247 on the more basic models to $29,469 for the most expensive. The boats can differ in size from 9.2 m to 9.3 m. The oldest one built in 1970 year. This page features Sparkman & Stephens and Sparkman and Stephens boats located in countries: Norway, Greece, Denmark and Kingdom of the Netherlands. To buy Iw 31 near you, use the search filter.

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SANITY is a Delta 94 designed by Sparkman & Stephens (#1899) and built by South Hants Engineering in 1980. We became her custodians on the 5th May 2017. This, hopefully humble offering is a tribute to the boat and our adventures with her.

Design #1899 Sail Plan - Copyright of Sparkman and Stephens

DESIGN SPECIFICATIONS

Name: SANITY

Type: She 31 /  Delta 94, a fin keel sailing sloop with an auxiliary 2YM15 Yanmar diesel engine

Designer: Sparkman & Stephens #1899

Builder: Hull constructed by South Hants Marine, Finished by, Laird Adams, Emsworth, UK

Date of build: 1980

Dimensions:  Dimensions from various sources - not verified and for guidance only

LOA: 9.24 m

Beam: 2.69 m

Draft: 1.65 m

Displacement: 3538 kg

SANITY in a bottle. A gift from the Fantastic Hayes family.

DELTA 94 HISTORY

Starting in 1968 -  I.W Varvet Ab boatyard of Sweden utilised the Sparkman & Stephens design #1899 as the IW 31. Approximately 350 boats were produced up until 1985 in three revisions.

In parallel to this South Hants Engineering (SHE) of the UK would commence production of the SHE 31 (S-31b) which was of the same design, later developments included the 9.5 Traveller a more spacious design with increased headroom and extended coach roof. Then in 1977 following a custom build the final iteration would be created with Laird Adams Engineering the DELTA94.

A longer attempt to summarise and comment on the various guises and variants of Sparman & Stephens design #1899

SANITY HISTORY

A BRIEF OVERVIEW:

2017 April: Change of ownership (Our custody commences) 2014 July: Change of ownership and name (REVID  to SANITY) 1989 June: Change of ownership and name (DELTA JUNO to REVID) 1980 February: Lloyds Register final inspection certificate dated 07/02/1980 No. 903401 1979 September: Agreement for construction signed with Laird Adams Engineering

" The Delta 94 should appeal to the committed yachtsman with a critical eye for a seaworthy boat and a feeling that yacht design since the Delta was drawn has progressed but a little way forward "

Yachting monthly 1980.

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• Sailboat Guide

She 31 is a 30 ′ 3 ″ / 9.2 m monohull sailboat designed by Sparkman & Stephens and built by South Hants Engineering starting in 1969.

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)

From BlueWaterBoats :

Penned as Sparkman and Stephens design #1899 by Olin Stephens, the SHE 31 introduced in 1969 has enjoyed popularity in the UK and Europe. Though originally intended as a half ton IOR racing thoroughbred, this boat often nicknamed a “baby Swan”, has gone on to be adapted for cruising in a myriad of derivative models. Known for her speed, close winded performance, and absolutely beautiful lines this racer/cruiser is often compared the Contessa 32 .

The unusual SHE name comes from the initials of South Hants Engineering, a UK light engineering firm founded in 1947 that branched out with a marine division. Headed up by two brothers, Derek and Simon Fitzgerald armed with an enthusiasm for sailing, the SHE line of yachts flourished from the late sixties to the mid seventies producing solely Sparkman and Stephens designs from the cramped SHE 27, the SHE 31 which was the most popular, the SHE 32, and the SHE 36 which was without a doubt the best boat in the line up.

The division ultimately succumbed to the financial climate of the late seventies and competition from cheaper, faster and roomier French imports. The company continues today as SH Enterprises but no longer produces boats.

The SHE 31 moulds were bought by Laird Adams Engineering who developed the design with increased headroom and a new, more practical interior. These boats sold under the name Delta 94 . Also there were a few examples that were home-built by enthusiastic amateurs.

The design, optimised for racing, was the beneficiary of Olin’s latest thinking in the same era of the legendary S&S 34 and Swan 36 both introduced 2 years earlier in 1967. He was a master of designing yachts to take maximum advantage of IOR rules for ocean racing.

Typical of these designs the SHE 31 has pinched bow and tail sections and a tumblehome amidships, reminiscent of much larger yachts. Her sharp bow profile gives her a good bite on tacks, and a swept back fin keel carefully faired into the hull with 3400 lbs of lead in results in a balanced feeling and stability in nearly all sea conditions. Notable is the skeg rudder pushed far aft and the propellor on a P bracket forward allowing better reversing.

There is accommodation for five but belowdecks it’s reasonably cramped with very little headroom, especially in the forecabin. The interior finish was restrained, modern and perhaps a little austere and betraying the use of ply.

Many variants were produced, we’ll summarise these below.

SHE 9.5 Traveller South Hants Engineering responded to public demand for a cruising model by producing the 9.5 Traveller, a version with more lavish accommodations;. It had a new deck, coachroof providing better cruising accommodations, higher topsides and increased headroom. Most owners will refer to their Traveller simply as a SHE. They are relatively rare.

Performance was still good and many examples will have been raced hard and spent long lives on exposed moorings rather than snug in marinas. Despite this, most have stood up well to the action, reflecting the high quality of build.

Delta 94/95 This particular boat caused quite a stir when she was unveiled to the yachting world at Southampton Boat Show in 1977. Produced by Laird Adams Engineering in the late senventies, the Delta 94 (also called the Delta 95) is a later version with the same hull, but with slightly more freeboard to produce more interior headroom, and a revised interior layout. Only 17 of them were produced.

IW 31 Simultaneously with the South Hamp Engineering yachts, Swedish builder I.W. Varvet on the island of Orust, an island which traces its roots back to the time of Viking ships, produced a large number of yachts. Over 350 boats were produced starting around 1968 in three revisions.

MK I (1968 – 1972): Small stern, ‘dinette’ layout. MK II (1972 – 1980): Larger stern, new deck, revised wood trim. MK III (1980 – 1985): Aluminium toe rail (instead of Teak), glass hatch, revised hardware.

Other Notes Please note the SHE 31B produced by South Hants Engineering from 1970 onwards was an altogether different design – being Sparkman and Stephens design #2042 which was also designated for 1/2 ton IOR racing. It was further developed into the SHE 32 – a more luxurious and roomier yacht intended for cruising.

Links, References and Further Reading

» Sailing Today Used Boat Test » Sparkman and Stephens Blog, SHE 31 / IW 31 » Sparkman and Stephens Blog, IW 31 / IW 31

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IW 31 - SHE 31

IW 31 - SHE 31 - Varvet / STW003726

Technical data

cabin cruiser

cruising/regatta

overall length

hull length

waterline length

standard draft

minimum draft

displacement

diesel tank

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Accomodation layouts

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DOCUMENTS: IW 31 - SHE 31

Sailplan drawing & measurements

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Technical forum: iw 31 - she 31.

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• Seitennavigation
• Highlights 2023

Der Klassiker

Die IW-31, von den weltberühmten Yachtdesignern Sparkman & Stephens, zählt heute zu den größten GfK-Klassikern die es überhaupt gibt.

Sie wurde ende der 1960er Jahre für die „Halbtonner“-Klasse, unter Berücksichtigung der damals gültigen IOR-Formel ( I nternational O ffshore R ule) konstruiert. Im Laufe der 1970er Jahre sahnte die IW-31 auf den internationalen Regattabahnen etliche Preise ab. Natürlich sind die Regattagene heute immer noch da und es macht einfach nur Spaß mit der alten Dame zu segeln.

Auf dieser Seite habe ich das Original Prospekt, Pressemitteilungen und diverse technische Daten für euch gesammelt.

Model: IW 31

Design: #1899

Builder: IW Varvet

IW 31 - CANTANA II

CANTELLA is an IW 31 - This attractive cruiser racer was built in 1969 by I.W Varvet Ab boatyard of Sweden. Approximately 350 boats were produced up until 1985 in three revisions.

IW 31 - Original Brochure

Design #1899 Sail Plan

Please note that Sparkman & Stephens Association Merchandise can only be purchased by members.

Strange Glow Over Moscow Skies Triggers Panic as Explosions Reported

B right flashes lit up the night sky in southern Moscow in the early hours of Thursday morning, new footage appears to show, following reports of an explosion at an electrical substation on the outskirts of the city.

Video snippets circulating on Russian-language Telegram channels show a series of flashes on the horizon of a cloudy night sky, momentarily turning the sky a number of different colors. In a clip shared by Russian outlet MSK1.ru, smoke can be seen rising from a building during the flashes lighting up the scene.

Newsweek was unable to independently verify the details of the video clips, including when and where it was filmed. The Russian Ministry of Emergency situations has been contacted via email.

Several Russian Telegram accounts said early on Thursday that residents of southern Moscow reported an explosion and a fire breaking out at an electrical substation in the Leninsky district, southeast of central Moscow.

Local authorities in the Leninsky district told Russian outlet RBC that the explosion had happened in the village of Molokovo. "All vital facilities are operating as normal," Leninsky district officials told the outlet.

The incident at the substation in Molokovo took place just before 2 a.m. local time, MSK1.ru reported.

Messages published by the ASTRA Telegram account, run by independent Russian journalists, appear to show residents close to the substation panicking as they question the bright flashes in the sky. One local resident describes seeing the bright light before losing access to electricity, with another calling the incident a "nightmare."

More than 10 villages and towns in the southeast of Moscow lost access to electricity, the ASTRA Telegram account also reported. The town of Lytkarino to the southeast of Moscow, lost electricity, wrote the eastern European-based independent outlet, Meduza.

Outages were reported in the southern Domodedovo area of the city, according to another Russian outlet, as well as power failures in western Moscow. Electricity was then restored to the areas, the Strana.ua outlet reported.

The cause of the reported explosion is not known. A Telegram account aggregating news for the Lytkarino area described the incident as "an ordinary accident at a substation."

The MSK1.ru outlet quoted a local resident who speculated that a drone may have been responsible for the explosion, but no other Russian source reported this as a possible cause.

Ukraine has repeatedly targeted Moscow with long-range aerial drones in recent months, including a dramatic wave of strikes in late May.

On Sunday, Moscow Mayor Sergei Sobyanin said the region's air defense systems had intercepted an aerial drone over the city of Elektrostal, to the east of Moscow. No damage or casualties were reported, he said.

The previous day, Russian air defenses detected and shot down another drone flying over the Bogorodsky district, northeast of central Moscow, Sobyanin said.

There is currently no evidence that an aerial drone was responsible for the reported overnight explosion at the electrical substation in southern Moscow.

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Things to Do in Elektrostal, Russia - Elektrostal Attractions

Things to do in elektrostal.

• 5.0 of 5 bubbles
• 4.0 of 5 bubbles & up
• Good for a Rainy Day
• Good for Kids
• Good for Big Groups
• Adventurous
• Budget-friendly
• Hidden Gems
• Good for Couples
• Honeymoon spot
• Good for Adrenaline Seekers
• Things to do ranked using Tripadvisor data including reviews, ratings, photos, and popularity.

1. Electrostal History and Art Museum

2. Statue of Lenin

3. Park of Culture and Leisure

4. museum and exhibition center.

5. Museum of Labor Glory

7. Galereya Kino

8. viki cinema, 9. smokygrove.

10. Gandikap

11. papa lounge bar, 12. karaoke bar.

• Statue of Lenin
• Electrostal History and Art Museum
• Park of Culture and Leisure
• Museum and Exhibition Center
• Museum of Labor Glory