Dashing to the snow in a supersonic jet

PHYLLIS BEACON-LAMBERT, of Camden Town, London, spends a lot of time wishing her friends a supersonic Christmas. Last Christmas she was one of 96 passengers to fly by Concorde from London to Finnish Lapland. ``I recommend it everywhere I go,'' she says. ``It was really out of this world.'' This seasonal day trip - which lasts 12 hours in toto and includes a twohour flight each way - is pure fantasy. Concorde goes faster than sound en route and climbs so high that (as Mrs. Beacon-Lambert recalls it) ``through the windows you could see the complete curvature of the earth, just like a round ball....''

Once in Lapland, Beacon-Lambert and the other passengers were driven through ``oh, beautiful wonderland scenery with all the log cabins, and all the log fires alight on the snow.'' (Nine times out of 10 you can be sure of a white Christmas in Lapland.)

The passengers drank hot reindeer milk and had their faces and necks rubbed with ice during a special crossing ceremony at the Arctic Circle. They went for rides down ``a large river'' on sleighs or snowmobiles. They had a meal with a choice of ``50 dishes'' (including reindeer meat, which in Finnish Lapland was untouched by radiation from the Chernobyl nuclear disaster). And they were given gifts made of Lapland silver: ``cuff links for my son and all the men,'' and for Beacon-Lambert and the other women, silver necklaces.

Best of all, she said, they met ``the real Santa Claus.'' She was convinced that at least his beard, which she ``held onto,'' was genuine - though official sources deny this. With typical journalistic skepticism, I asked Boris Taimitarha, head of the Finnish Tourist Board's London office, if he could tell me the true identity of the man who - all year round - is the Official Lapland Santa Claus. Mr. Taimitarha telephoned Rovaniemi, where Concorde lands, to ask local officials. Their answer, however, was: ``We are sorry, but in order to keep a certain mystery about Santa Claus, we must decline to reveal his real name.'' Nevertheless, Taimitarha comfirmed that ``Santa'' has his own post office from which he replies to all the children who write to him throughout the year.

The Christmas Concorde flights, now in their third year, cost almost 1,000 per seat. But when one compares that figure with the cost and journey time of ordinary flights that trace the same route (some 530 one way for a flight that takes seven hours), it is clearly not as excessive as it seems. Beacon-Lambert says that ``it was worth every penny we spent on it. ... Mind you, we're not rich people.''

The flights are always fully booked and the firm that charters them, Goodwood Travel in Canterbury, England, has a long waiting list. ``We have five bookings already for next Christmas,'' said the firm's Jan Knott.

Mr. Knott believes the Laplanders will turn out this Christmas, as in years past, to welcome the plane. ``The first time about 20,000 ... came to see us arrive - something like 90 percent of the population of Rovaniemi. And they still come.''