420 class

Technical details

The 420 is an established performance two person trapeze and spinnaker racing dinghy. There are 56,000 worldwide. This popular dinghy is sailed at school, club, open, national and international levels in Fleet and Teams Racing. The 420 is the ISAF Youth World Championship boat and a youth development boat in 43 countries. The 420 is used for the World Teams Racing Championships and now for teams racing at a secondary school and inter club competition level in New Zealand. Despite being new to New Zealand it is fast becoming a major yacht class due to its all round performance and these multi-use attributes.

For the most comprehensive guide to all aspects of 420 sailing, class rules and ISAF 420 rules, go to the British International 420 Class Association technical information page

The boat specifications

Length 4.2 m

Beam 1.63 m

Mast 6.26 m

Sails Main 10.25m2, Jib 2.8 m2, Spinnaker 9 m2

Bare hull weight 80 kg min

Sailing weight 100 kg min - the ideal competitive combined crew weight is 110-145Kg

Sail setting and trimming tips


Top Batten- Just tight enough to remove wrinkles from the pocket, until over 15 knots, when it should be quite firm.


LIGHT -firm

MEDIUM -eased a little so the foot shelf just “falls in”.

HEAVY -mega tight


LIGHT -just enough to remove major wrinkles

MEDIUM -remove most wrinkles

HEAVY -tight to very tight.

Main Sheet

LIGHT -top ribbon to flow at least 50% of the time

MEDIUM -top ribbon to flow around 70% of the time

HEAVY -you will be vang sheeting now, see below


LIGHT -take it off the boom and clip it to the shroud

MEDIUM -none, get all your leech tension through mainsheet. Start using vang when easing main to de power.

HEAVY -Continue to pull more vang on to control leech twist, and aid mast bend. More and More!!!


Height -The tack of the jib, when tensioned should be no higher from the deck at the forestay fitting than 40mm.

Luff Tension -Always enough to remove any wrinkles, except for very light winds (off) and heavy wind (lots on)

Sheet Tension -In nearly all but heavy winds, the jib must be not only sheeted, but also “barberhauled” using the windward jib sheet to bring the sheeting angle of the jib closer inboard, resulting in greater height and speed.

LIGHT – with crew to leeward or in the middle of the boat, trim the jib so it is barberhauled, with the sheet eased to allow the leech ribbon and top leech telltales to flow.

MEDIUM – Pull the jib sheet in firm, then barberhaul very tightly. You will now need to ease the sheet to get the ribbon and leeward telltale to flow 90% of the time. The crew, if on trapeze, should be able to “walk forward” and check it out while on the wire.

HEAVY – As you vang sheet, and start easing the boom off centerline, you should start using progressively less barberhaul, until it’s blowing hard and you're using none!