Sail system with adjustable sail area

A sail system for a wind-driven craft having a mast and a boom, said sail system comprising:

• an upper sail section having a luff securable adjacent the mast, a leech extended distally from the mast, a foot at the bottom thereof extending between said luff and said leech, a tack at the juncture between said luff and said foot and a clew at the juncture between said leech and said foot;
• a lower sail section having a luff securable adjacent the mast, a leech extended distally from the mast, a foot at the bottom thereof extending between the luff and the leech, a tack at the juncture between the luff and the foot, and a clew at the juncture between the leech and the foot;
• readily removable attachment means to continuously seam the upper edge of said lower sail section to the lower edge of said upper sail section from said tacks to said clews;
• means for adjusting the effective height of the mast between a first extended height when the lower sail section is attached to the upper sail section and a second height when the lower sail section is removed from the upper sail section, said second height being lower than said first height by an amount approximately equal to the length of the luff edge of said lower sail section;
• the free end of the boom being secured to the clew of the lower sail section when the lower sail section is attached to the upper sail section and with the free end of the boom being secured to the clew of the upper sail section when the lower sail section is removed from the upper sail section, and also with the tack of the lower sail section being downhauled adjacent the lower portion of the mast when the lower sail section is attached to the upper sail section and the tack of the upper sail section being downhauled to the lower portion of the mast when the lower sail section is removed from the upper sail section;
• first batten pocket means formed on the upper sail section;
• second batten pocket means formed on the lower sail section in alignment with said first batten pocket means;
• first batten means insertable in said first batten pocket means;
• second batten means, the lower end of said first batten means being removably engageable with the upper end of said second batten means;
• and
• retainer means on said sail sections to removably secure the batten means within their respective batten pockets.