THE GREATEST disaster in ocean racing history occured last summer when a severe storm struck the more than 300 yachts competing in the bienial Fastnet race, the crowning event of Cowes Week, the premier event of British yacht racing. The turmoil of that night of August 13/14 has left three questions which sailors and experts will be debating for many a long year: what happened; why did it happen; and what could have been and now should be done about it?

John Rousmaniere's and Roger Vaughan's studies of the race and storm are only two of the many books the disaster will produce. The primary document remains for the moment the report of the inquiry into the race conducted by the Royal Ocean Racing Club and the Royal Yachting Association, published last December.

John Rousmaniere's book is a useful, readable and throughly sane introduction to the basic facts, individual experiences and underlying issues of the 1979 Fastnet disaster. Although the material is badly organized, jumping suddenly from anecdote to analysis and back to anecdote, it is written in the good muscular style of a competent journalist with all the necessary sailing experience and specialist knowledge.

Roger Vaughan's book, though containing some-indulgent, autobiographical and slangily written to be appreciated by anyone reared in the best tradition of nautical writing, which prefers bald accounts, understatement, simple prose minimal "philosophy."

What happened on that terrible night -- and the present reviewer, who witnessed it from the comparative safety of a small Irish harbor six miles from the Fastnet Rock keeping anxious anchor watch in wind speeds which consistently exceeded the 60-knot maximum reading on his boat's anemometer, will never forget it -- can now be starkly summarized.

The Fastnet course runs 600 miles from the Isle of Wight in the middle of England's south coast, round Land's End at the southwestern tip of England, up to the Fastnet Rock off the southwest corner of Ireland and back round the Bishop Rock, off the Scilly Isles, to the finish at Plymouth on England's south coast. In all 303 yachts of between 28 and 79 feet overall length started the race: 85 finished, after 194 had retired, 19 had been abandoned and five had sunk.

Out of 2,700 crew members 15 were lost, and 136 were saved from sinking yachts, life rafts and the sea itself. Nothing remotely comparable had ever occurred before in the more than 50 years of popular ocean racing. Less than 40 people have died in ocean racing in a total history of over 100 years. In the 55-year history of the Fastnet race there had been one previous death -- 48 years earlier. More astounding still, of the 180 yachts under 39 feet in length, only 13 finished the race, 144 retired and 23 were abandoned or sunk. Almost half the boats in the race were at some point knocked flat in the water or almost flat; and one-third were knocked down beyond horizontal or rolled right over through 360 degrees.

Even the largest boat in the race, Jim Kilroy's Kialoa with an overall length of 79 feet, was knocked flat; and she was not at that time in the area where the most vicious seas developed, namely a circle with a 40-mile diameter centered 70 miles west Northwest of Land's End. The reason why most of the damage in the race occurred to smaller boats was not that they were smaller, but that they happened by bad luck to be concentrated in this particular area during the worst of the storm.

The direct cause of this catastrophe is clear. Sea-going is in essence a horizontal activity, and on the night of August 13/14 the marine environment between Land's End and the Fastnet Rock became effectively vertical.

The damage was done by the waves -- up to 40 feet in height, almost vertically steep and frequently breaking over boats caught in their path -- and not by the storm-force winds. The wind, however, caused the high seas.

The cause of these very high winds -- a steady average of Force 10 (48-55 knots) and frequent violent gusts about 60 and possibly as high as 70 knots -- was a small, fast-moving and eventually deep depression (below 980 millibars), born in the northern Great Plains of the United States on August 9 and which swept into the Fastnet sea area during the night of August 13/14. The ferocity of the resulting seas was a direct consequence of the strength of the winds, blowing over open ocean for several hours, and of the fact that the direction of the wind swung from south to northwest in 12 hours, thus causing wave motions coming from many directions at once.

More than half the participants in the race believed that the steep seas were also caused in part by the Labadie Bank (depth 40 fathoms, with 21 to 25-fathom patches, compared with an average depth of 65 fathoms in the Western Approaches), A long tradition of seafaring lore corroborates this opinion. But Britain's Insititute of Oceanographic Sciences told the offficial inquiry that the Labadie Bank could not have influenced wave height or shape.

In the wake of the disaster much nonsense was talked on all sides about how it could have been avoided. Grave errors of weather forecasting were alleged. Skippers were accused of bad judgment in taking to life rafts. Inexperience in handing small boats in storms, excesive racing zeal, excessively light and defective design of boats and rigging and general weaknesses of character and fortitude were all alleged against the less fortunate boats by those who were safely on shore or who were lucky enough to survive without serious damage.

Careful examination of the facts shows all these charges to be unfounded. There were only two ways to avoid disaster that night: either not be there at all; or to be lucky. There was no way that the storm and the resulting sea state could have been forecast in time to make a significant difference to the number of boats affected. The racing authorities had no reasonable cause to cancel the race. No differences in radio communication or boat design or seafaring experience would have significantly altered the outcome.

The plain fact was that a storm of extraordinary, though not totally unprecedented, force happened to strike a small area in which there happened to be an extraordinary -- and unprecedented -- concentration of small boats and for many crucial hours created a marine environment in which, for the unlucky, it was simply impossible to avoid disaster.

John Rousmaniere well summarizes the sensible findings of the official inquiry:

"Neither two-way factor would have forestalled disaster, the committee appeared to conclude. This was an experienced group of sailors exposed to an exceptionally severe sea condition. Some of the boats may not have been quite as stable as they should have been, and some equipment should have been stronger, yet as elucidated in the reporter's last paragraph, the lesson was: 'In the 1979 race the sea showed that it can be deadly enemy and that those who go to sea for pleasure must do so in full knowledge that they may encounter dangers of the highest order.'"

The only people to emerge with discredit from the whole tragedy are the busybodies and wiseacres who, after the event, claimed that this, that or the other reasonable precaution could have prevented the disaster or who claim that some new bureucratization or regulation of seafaring is necessary in order to prevent the minute risk of a repetition. The truth is, as with so many others of the hazards of contemporary life which the sedentary" committee" mind cannot tolerate, that the costs of reducing such risks to zero greatly exceed the benefits to the human spirit and personal fulfillment of cheerfully accepting them.

There is not a good seaman who would have been in the sea area between Land's End and Fastnet Rock that night if he had known what the sea conditions were going to be. But also there is not a seaman who would not have been there on the evidence that was reasonably available at the time or who would wish to be prevented from being there by some new regulation imposed over his own seafaring judgement.

The fascinating story of the Fastnet disaster is thus at one and the same time as series of individual dramas, a meteorlogical and oceanographic puzzle and a philosophical exercise in the perennial moral and political problem of the proper balance between the individual's right to incur risks and the duty of governments and otehr authorities to protect people from the possibility of misfortunes which may overtake them.

The most difficult thing in the world for committees, for politicians, for the media and for other experts to accept is that such-and-such a disaster occurred and absolutely nothing should be done in the future to prevent it happening again. Yet, the Fastnet disaster may have done a service to mankind by demonstrating that there are indeed occasions when this is the right thing to say and that, if such occasions exist in ocean racing, they may also exist much more widely than is recognized in other aspects of society where the mania for "absolute" safety is involving us in a greater and greater risk of "absolute" regulation and "absolute" inactivity.