75 Years of crafting the best cruising sails

The Semi Square Head

Why Choose a Semi Square Head?

Challenge

  • Wish to have better performance
  • Wish for a classy looking sail
  • Wish to refine your sail tuning

Result of a semi square head main

  • Increased performance
  • More power even when reefed down
  • Higher off-wind efficiency
Catamaran Mainsail Semi squarehead fathead multihull mainsail
Semi Square Head Mainsail
May we introduce

The Semi Square Head

This sail is taking the concept of the large roach mainsail one step further. Originally made for performance offshore racing yachts, square-top mainsails have now also found their way on board more moderate cruising yachts. The semi square head is the middle way between the max-roach main and the radical, full square head sail. It delivers more power but is slightly less of a challenge to handle, especially when taking down and folding on the boom, than the full square head mainsail.

As in the max-roach sail but in a greater measure, the sail will twist to leeward on the top section when hit by a gust, de-powering and lowering the centre of gravity instantly. This can help to prevent overpowering and might tempt the crew to reef later than they otherwise would.

What's in the box?

Standard Specifications

Options and Accessories

1 Semi Square Head Mainsail
Your sail will be carefully designed, inspected, packaged, and shipped.

Compare Our Multihull Sails

Material
Premium Dacron
Performance
75%
Durability
90%
Price
$$
Colors

Semi Square Head Mainsail

Catamaran Mainsail Semi squarehead fathead multihull mainsail
Material
Premium Dacron, Hybrid Dynema
Performance
80%
Durability
80%
Price
$$$
Colors
Material
Premium Dacron, Hybrid Dynema
Performance
85%
Durability
70%
Price
$$$$
Colors
Material
Premium Dacron
Performance
75%
Durability
90%
Price
$$
Colors
Material
Premium Dacron, Laminate
Performance
85%
Durability
80%
Price
$$$
Colors
code zero lagoon 46 catamaran 04
Joe Fox, TMG Yachts
5/5
Well made, easy to operate and a gamechanger
We have ordered a number of Code 0 sails now from Greg and Sam at RTS Australia for both company use and client vessels. The service has been excellent, professional and always a prompt reply. The loft is helpful with meeting production requirements and sails are always delivered on time. For a good quality good value sail you don’t need to look past RTS. After sales support and advise is always forthcoming when needed and Greg and Sam come with a huge amount of hands-on experience which goes a very long way. The Code 0 itself is well made, easy to operate and a gamechanger on all the vessels well have fitted them on.

Choose your Sail

Required Measurements

mainsail measuring form
Download Mainsail Form PDF
This is how it’s done

Buying New Sails has Never Been Easier

2 Semi Square Head Mainsail

Choose your sails and get a quote

Fill in the form as far as you like, hit send and get the ball rolling.

3 Semi Square Head Mainsail

We contact you within a few weekdays

To answer all your questions and advise you on your individual sail. You will then also get your final quote.

4 Semi Square Head Mainsail

We deliver your new sail swiftly

Depending on your location and time of ordering, you will receive your new sails within a few weeks.

5 Semi Square Head Mainsail

Enjoy your sailing!

Hoist your brand-new sails and enjoy a whole new sailing experience.

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