In Brief

Southern Cross 31 Sail Plan
The Southern Cross 31 is a no nonsense double-ender designed by Tom Gillmer, a professor of naval architecture at the US Naval Academy. The design takes influence from shapes dating back to Colin Archer’s work nearly a century earlier, and the hull in many respects is similar the straight transomed Allied Seawind 30, an earlier Gillmer creation notable for being the first fiberglass boat to circumnavigate the globe. (The Allied Seawind 30 was successful enough to be updated to the Allied Seawind II)

She’s a full keeled sailboat with an outboard rudder and tiller combo, a configuration often praised for its simplicity and the cockpit is quite small, suitable for ocean passages. The cutter rig with bowsprit has 447 sq. ft. of canvas, plenty for its displacement, but being a heavy displacement boat performance is hampered in light airs. Looking on the bright side, the weight gains dividends with a comfortable motion while underway.

Two interior layouts were offered, one with a stand up navigation station over a large locker and one with quarter-berth. The overall construction quality was of a good standard, suitably strong for offshore work. The hulls were built in fiberglass with the topsides cored in Airex foam, while the deck and cabin house was cored in balsa.

In total 130 boats were built between 1976 and 1987, of which a number were sold as hull and deck kits. A slightly larger and similar Gillmer design is the Aries 32 (around 20 of these were built).


LOA: 31′ 0″
LWL: 25′ 0″
Beam: 9′ 6″
Draft: 4′ 7″
Displacement: 13,600 lbs.
Ballast: 4,400 lbs.
Sail Area: 447 sq. ft.

Designer: Thomas S. Gillmer
Year Introduced: 1976
Year Ended: 1987
Builder: Clark Ryder, Bristol, Rhode Island.

Similar Boats

Allied Seawind 30
Aries 32
Mariner 31

Links, References and Further Reading

» Southern Cross Owners Association
» Twenty Small Sailboats to Take You Anywhere by John Vigor, (Ch19, p117-123) an in depth look at the Southern Cross 31. ISBN:978-0939837328
» Ryder Yachts


Southern Cross 31 Sailboats for Sale

NEW! List your boat for sale right here. Pricing is $50 per listing until sold.

Please contribute additional information about this boat...

Add your stories, experiences, tidbits, updated information - whatever you think is useful to others.

9 thoughts on “Southern Cross 31”

  1. Andy Panama says:

    Good day. Just bought a 1981 southern crops 31 but cannot find sail plans/drawings or more data. Also would like to know where can get spares like sail gears elements, gallery, bilge pump, electric elements, etc. I know I can get generic easy, but do no know if original spars can be found with a reasonable prices. Any help on above?


    I´m trying to find out the correct mast and boom lenths for y reconstructed southern cross 31. tnx paul

    1. ERICK says:


    2. duncan mcgregor says:

      Hi Paul
      bit late i think but I have quite a number of plans for my boat as it was built from scratch in 1973 (UK),these plans are for the kit version of the double ended southern cross 31′
      if you still require any information ?


  3. Vern Bastable says:

    My Southern Cross 31 sailed herself from Connecticut to Bermuda and despite being dismasted and the loss of her rudder she was afloat and was easily restored to original condition. I feel she is so capable she will always get me home no matter how far away home is…

  4. Vern Bastable says:

    My Southern Cross 31 which was built in 1984 as Hull # 104 sailed herself from Connecticut to Bermuda and had a new rig and rudder added to replace the lost ones… Despite this extensive damage she was still afloat and now is fully restored. I feel she is so capable that she will always get me home safe no matter how far away home is!

    1. Dennis Hoak says:

      I have hull #103 builtin 1980. The yearsand hulls don’t match …

    2. Vern Bastable says:

      Dennis you are correct the year built was incorrect… It was 1980 not 1984 mine was built in.

  5. Odd Arild Ertvåg says:

    An even earlier Gillmer-comstruction (and almpost similare to Southern Cross 31) is the Aries32 (also buildt as Roughwater 33) from the late 60`or early 70`. O.A.Ertvag

Leave a Reply