NorthU Sample Chapter: Performance Racing Trim

Excerpt from Performance Racing TRIM, Chapter 11, Section 3, Pages 142-143

Spinnaker Trim - Reaching Trim - Sheet Trim

Spinnaker trim requires the trimmer's full undivided attention. The sheet should be played constantly. An overtrimmed spinnaker is slow. Ease to a curl and trim, ease and trim. If the trimmer stops playing the sheet the boat speed will suffer; and if the trimmer fails to give the spinnaker his full undivided attention the spinnaker will collapse in a fit of jealous rage. Fig. 3 (right).

The spinnaker telltales can help with sheet trim. The outside telltale is the important one - if it stalls the sail is overtrimmed. On a broad reach the telltales may not fly, but keep playing the sheet.

Fig. 3 (above): Spinnaker Sheet, and pole height. Play the sheet constantly - ease to a luff and trim, ease and trim. Play the sheet constantly. The pole height here is correct, with good shape across the sail.

Pole Height
Pole height is controlled by the topping lift. Starting from our initial position with the clews even we can fine tune to draft position. Lowering the pole will pull the draft forward, just as adding luff tension pulls the draft forward in other sails. It creates a more open leech, and a rounder entry. On a reach the tack will be slightly lower than the clew. Correct pole height is shown in figure 3.

If the pole is too low, the shoulder along the luff will cave in, and the leech will twist open, spilling power. Fig. 4, below.

If the pole is too high, the luff will fall to leeward, and the leech will close, creating excess heeling force. Fig. 5

Pull the draft just forward of the middle of the sail. On heavy air reaches a low pole will prevent the draft from being blown aft. In light air a high pole position, with the clews even, will provide extra power.

The heel of the pole on the mast should be adjusted to keep the pole level, but donšt sweat it if the pole is six inches out of level.


Fig. 4 - Here, the pole is too low. The upper luff is caving in, and the leech is spilling open	Fig. 5 - Here, the pole is too high. The upper luff is falling away, and the leech is closed. A proper sail shape is silhouetted for comparison.

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