Without compromising the family image of trailer yachts, many are being geared up to race with extras as more owners become involved in mixed fleet racing. And for many owners, spinnaker gear is the big step into competitive sailing. Given the size of boats involved, it is a relatively inexpensive way of boosting performance, and while adding spinnaker gear might unnerve those used to poling out a headsail, it need not mean replacing the family crew with hired heavies.

Basically setting a spinnaker on a trailer yacht should not require more than three people, including the helmsman who can hold the brace or sheet. For really comfortable sets, a crew of four, with the lightest member on the foredeck, can handle anything.

However, there will be days, in strong winds, where control down- wind will be difficult and it will still be fast, as well as prudent, to pole out the headsail instead of setting a spinnaker. As nearly all trailer yachts are light-displacement types they don't need to be pressed hard to get their best performance.

Your spinnaker package need not be more than one spinnaker, one alloy or home-made timber pole, two sheets (twice the length of the deck) two halyards, blocks on the mast and bits of line and shock cord to make up a control system for the spinnaker pole. Cloth weight is usually 3/4oz, though some special reaching spinnakers may be cut in a heavier weight such as 1.2oz.

With most trailer yacht spinnakers under 300sq ft in area, a lot can be learned from the big dinghies, though one has to remember that a trailer yacht does not have the benefit of the stability leverage of a crew on trapeze and so one cannot carry spinnakers as easily on a tight reach as high performance dinghies.

In setting up the spinnaker gear, some trailer yacht owners suffer from delusions of big-boat grandeur. They load up their boats with dip-pole systems and other blue-water paraphernalia. Considering the size of boat involved, it is all unnecessaiy. All trailer yachts, including the big ones, are sensitive to the movement of crew weight and will be badly stopped by 90kg of crew bouncing around the foredeck. With this in mind, the spinnaker system should be set up to reduce crew movement to a minimum.

One can easily adapt a dinghy style spinnaker pole-launcher to the boom of a trailer yacht to save one crew movement in a spinnaker set. The pole should be gybed by the for 'ard hand at the mast and, to further save crew movement on the foredeck, you can learn to set the spinnaker out of the for'ard hatch instead of out of a bag on the bow.

The for'ard hand should ideally be the lightest member of the crew and the only person to get as far for'ard as the mast while racing. If you are all heavy, just substitute "sure-footed" for "light".

Preferably the halyard will be led internally down the mast with a light braid existing at deck level and running back to a jam cleat. The topping lift for the pole is usually a simple affair with a small, heavy-duty swivel block hanging off a tang midway between the spreaders and the jib head.

A single set of sheets (twice the length of the deck) of around 8mm diameter act as sheet and brace and are led aft through single blocks (not swivel) mounted a foot or two in from the transom. If no sheet winches, fit ratchet blocks.If you have a pop-top to contend with, run your halyards, vang control, cunningham and pole downhaul out from the mast to plastic deadeyes and then around the pop-top, aft to the cockpit.

The most popular and best-known spinnaker pole system (Figure 18) is the basic end-for-end gybe system that has the topping lift and down- haul attached to the middle of the pole. The pole has its spring-loaded piston end fittings released from the brace, or ring on the mast, by simply pulling a light cord which runs to the middle of the pole. The cord is tied off at the mid-point on the pole so you don't trip both ends of the pole at once.

When the pole is gybed, the end that was on the mast goes onto the new brace. The for'ard hand has to be careful not to collapse the spinnaker as he grabs for the new brace.

In the left-hand drawing of (Figure 18) the kicker (or foreguy) is led to the foot of the mast, rather than to the middle of the foredeck as in the traditional end-for-end pole system, so you don't have to continually let off the kicker to brace for'ard or aft.

One good dinghy idea that can be employed with the above system is to replace the rope kicker with one of shock-cord and use the brace as a kicker and brace combined. This is achieved by holding the brace down at deck level by a hook on the gunwale mounted just aft of mast level. The steep angle of the brace off the deck stops the pole from skying. The controls are simplified to just brace, sheet and topping lift with the shock-cord acting as kicker when the wind is light and the pole squared right back (centre, (Figure 18).

When the boat has a skeg through which the board protrudes, this gives some tracking without the board, so generally the board can be right up downwind at all times, except:

• Running almost square in light airs and sloppy sea, or

• Shy reaching to make a mark, luffing and responding to a luff.

In these two situations the board should be about 12% down. If the boat is underpowered it is usually because of the ratio of sail area to hull and crew weight and it pays to tack downward in light airs as the increase in boatspeed more than offsets the distance covered.

Trailer yachts without the skeg- type arrangement need some board down all the time.

Be careful to ensure that the board is not down more than vertical as this will accentuate weather helm; conversely, if weather helm is a problem try lifting the board (if pivoted) a little as this will shift the centre of lateral resistance further aft and so help balance the sailplan. However, first check that the leading edge of the rudder blade is vertical as rake in this will quickly accentuate weather helm.

Most trailer yachts respond well to having the centreboard lifted, in varying degrees in fresh going where it is important to keep the boat on its feet. In fresh conditions, keeping the boat moving is more important than pointing ability and while the board up a little decreases the latter, it improves the former. By keeping upright and travelling fast the boat makes less leeway and so speed made good to the weather mark is often better.

IMPORTANT NOTE: Be aware of the risk of sailing with the board partially or completely raised. For racing, sailing instructions may require the board to be kept locked down.

Most trailer yachts, being light- displacement designs, are affected by excess weight. If planning to race, give the boat a break and leave behind all unnecessary gear and equipment which tends to mount up, particularly when the boat is used as a caravan.

Concentrate all gear around the vicinity of the mast. Take the anchor out of the foredeck locker and all spare sheets, blocks and tools from the cockpit seat locker. The fuel tank can be well topped up if kept below as the outboard motor is enough to have to carry right on the stern.In light airs keep crew weight forward so that the stern is only just in the water (with some very wide, flat- sterned boats, just out of the water). This usually means two crew (one .may be the skipper) in a three-man boat down to leeward. This applies both on and off the wind as the object of the exercise is to reduce wetted surface area. Once the boat picks up speed (reaching) in light airs adjust crew weight, angle of heel and fore- and-aft trim to pick up waterline length for optimum hull speed.As the wind increases, move the crew weight progressively further aft shy reaching and running in fresh breezes in particular as this utilises the wider, flatter sections of the boat to gain stability.

With eased sheets, especially on a reach, always trim the main and genoa together. The sails should be working parallel all the time. The ideal set-up is to have two people who can work together, one trimming each sail.

In hard reaching when excess weather helm is developed, ease the genoa as well as the main. Ease the genoa even past the point of luffing if necessary. More reaching legs are lost when under main and genoa only, because the main is eased but not the genoa. You seldom see a boat suffering from broaching problems when reaching under mainsail alone.

Often described as "sailing by numbers" the use of adhesive decals for marking such adjustables as halyards, outhaul, cunningham, backstay, genoa leads, mainsheet traveller etc, is well worth while. It is simpler to record that "No 1 genoa sheets on #4 with halyard mark on #6 for moderate airs" than to have to tune the setting on each occasion. I suggest keeping a diary to record these variables and so make your sailing life a lot easier (Figure 21).