Classic_Boat_2016-10

78 CLASSIC BOAT OCTOBER 2016

Classnotes

BY VANESSA BIRD

D

espite initial resistance, the

OK has gone on to become

one of the most successful

singlehanders of its generation.

Ironically, for a class now popular in

over 40 countries worldwide, at the

time of its launch, many clubs in

Denmark tried to ban the design for

being unseaworthy. Used to the

stability of the Junior-boat keelboat,

which many of Denmark’s young

sailors cut their teeth on, the

cat-rigged centreboarder, with its

tendency to capsize if not correctly

balanced, proved an interesting

challenge, and one that some clubs

declined to partake in.

It was designed by the Dane Knud

Olsen, who during the 1950s worked

for speedboat manufacturer AP

Botved in Vordingborg. In his spare

time, he produced a number of

designs, including one for a

bermudan-rigged dinghy. But it

wasn’t until sailor Axel Damgaard

Olsen approached him in 1956

requesting a design for an inexpensive

singlehander for racing that this

design came to fruition. Axel

Damgaard Olsen recognised that

there was a need in Denmark for a

new dinghy design alongside the

existing popular classes of the 15ft

6in Snipe, the 16ft 4in Pirat and the

14ft 9in Finn. It had to be suitable for

amateur construction at home,

inexpensive, and capable of being

transported on the top of a car roof.

Knud Olsen’s design fi tted the spec

perfectly, and following involvement

from Finn sailor Paul Elvström with

the rig design, the fi rst OK was

launched in 1956. Seventy more were

built that winter, and by the end of

1957, Hvidovre, Copenhagen

Amateur Club, Helsingør and Dragør

sailing clubs had established fl eets and

were organising regular races.

Axel Damgaard Olsen helped

spark interest further afi eld, too.

Wherever he went, he took one on the

roof of his car, and fl eets were soon

established in Norway, Germany and

the USA. He was also helped by Finn

sailors Paul Elvström and Richard

Creagh-Osborne, who promoted the

class in Europe, helping to establish

production and fl eets in the UK,

France and Sweden. It was popular in

Sweden, where between 1961–64,

1,200 boats were built, and it was

seen as a training boat for the Finn.

The OK is a one design, but

although measurements are strict,

some fl exibility in the hull is allowed.

The hull is hard chine, with a deep V

section and slight rise to the chine at

the bow. Originally, they were built of

ply – from plans or kits – but GRP

construction entered the class in

1965. Jeremy Rogers, who later
      became known for the Contessa 26
      and 32, built over 80 GRP boats in
      the UK between 1965-66, alongside
      Pamcraft in Australia, where it had
      been introduced in 1958-59. Today,
      epoxy sandwich hulls are the norm,
      and the unstayed, rotating, bendy
      mast, which is set well forward in the
      bow, is carbon. The class is sailed
      from the UK to Denmark, USA, New
      Zealand and Africa. It was granted
      International status in 1974, and
      many of the world’s top sailors have
      learnt in one, and, at the same time,
      helped confi rm its reputation as one
      of the best singlehanders of its era.

OPTIMISTS

Not only did Axel Damgaard Olsen

help create the OK dinghy, but it

was also thanks to him that the

Clark Mills-designed Optimist was

introduced to Europe. Following a

trip to Clearwater in Florida,

Olsen brought plans for the 7ft 9in

dinghy home to Denmark and

helped promote it. It has since

become one of the most popular

dinghies in the world.

THE NAME

The OK takes its name from the

initials of Knud Olsen. However, ko

in Danish means ‘cow’, so it was

decided to reverse the letters.

JUNIOR VERSION

In the early 1960s, in a bid to allay

concerns among Danish sailors

regarding the OK’s suitability as a

racing dinghy and its tendency to

capsize, the OK-Junior was

introduced. This version of Knud

Olsen’s design featured the same

hull as the original, but the rig was

reduced by 20sq ft (1.9m^2 ) to

70sq ft (6.5m^2 ). Needless to say, the

new design did not catch on and

was soon forgotten.

DESIGN CHANGES

The design of the OK is governed

by the class measurements, which

allows a reasonable amount of

leeway in hull design.

However, in 1957-58, new rules

specifi ed a watertight bulkhead at

the forward end of the cockpit for

added buoyancy, and additional

tanks could be placed under the

sidedecks if required.

The latter tweak was retracted

after it was discovered that the

increased buoyancy made the OK’s

hull fl oat too high in the water

following capsize, which made it

diffi cult for the helm to get

back on board.

© RODNEY TIDD

SPECIFICATIONS

THE INTER-

NATIONAL OK

LOA

13ft 1in (4m)

BEAM

4ft 7in (1.42m)

DRAUGHT

2ft 9in (0.9m)

DISPLACEMENT

159lb (72kg)

SAIL AREA

96sq ft

(8.95m^2 )

DESIGNER

Knud Olsen

The International OK

Vanessa’s book Classic

Classes comprises 140

of the most enduring

keelboat and dinghy

classes. Available at

£17.99, bloomsbury.com

Above: the

International OK

was designed in

1956 for

home-building,

and is now

sailed in 40

countries

worldwide

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