Sail ho!

Sailing has its seasons - and they last all year.

In summer the tip of the sailing iceberg shows most spectacularly, as ballooning rainbow spinnakers prance and pull across lakes, rivers, bays, and oceans.

Summer brings dawn parades of mushroomlike sailbags; swarms of dinghies in crazy quilts that zigzag at the starting line; flying-trapeze artistry to balance hull against gusting wind; instant drenchings in rain squalls and half-intentional capsizings; the long trudges home at dusk, musing over how that other boat caught the tide rip just right to drive her over the finish first.

Early spring often is forgotten in the summer's race campaign, but it is a vital time of preparation, with long hours spent polishing hulls to the mirror sheens that capture silver. Those who neglect spring preening and find themselves lagging in the races to come may well marvel at the skippers in the lead, whose taut rigging and exquisitely tailored sailcloth are evidence of the year-round work that marks a trophy winner.

Autumn, too, rewards the sailor. There's time for contemplation, discussing the season's record, ordering a recut jib, and deciding if it's time to try a different boat.

Winter comes quickly, and with it last year's shipyard bills. Some sailors are doubly grateful with each swell of inflation for the switch from a wooden hull (so warm and lively, but needing costly scraping, sanding, caulking, and painting each year) to carefree fiber glass.

Winter, too, means following long distance the millionaires on the international yachting circuit - and with them, those hardy crewmen who uphold the grand sea tradition of leaving behind land and family, career and all, for life before the mast.

For the landlocked spectator, the gentle weekend sailor, as much as for the ocean racer, sailing means what it has meant for countless generations - new and often surprising understanding of wind and nature.

The days are gone when discoveries were made by tall ships at sea. Gone, too , the time when a venturesome lad took to the sea and traveled the world with no passport other than his knowledge of trimming sail and holding course.

Wind tunnels, testing tanks, and computer programs have turned the art of sailing into a science - almost. But what lasts is the reason that still urges men, women, and children to hoist sail.

Each one sails to test himself, to understand how he can fit himself to nature's forces - and how to use the wind to drive him wherever he would go.