Increasing jib halyard tension causes the jib to become which?

• A. Fuller with draft aft
• B. Flatter with draft forward
• C. No change in draft
• D. Heavier luff

Answer: (B)

Increasing jib halyard tension tightens the luff, pulling the forward edge of the sail closer to the mast. This extra luff tension flattens the sail, reducing its depth (draft) and moving the deepest point forward toward the luff. This flatter shape is advantageous in stronger winds or when sailing more upwind, as it lowers drag and smooths the flow over the sail. If you loosen the halyard, the luff slackens, the sail becomes fuller, and the draft tends to shift aft. The other descriptions don’t match how tightening the luff affects sail shape.