The anniversary of the Great February Snow was approaching, and there in the shop window was a five-foot Flexible Flyer. I have been a sucker for five-foot Flexible Flyers since World War II, and especially since the Christmas when my father gave me one and I wiped out every kid in the neighborhood and then wiped out the sled on a tombstone.

Buying the new sled was a reflex action I couldn't control even though it wasn't a real Flexible Flyer. The maker of that finest of all sleds, the S.L. Allen Co. of Philadelphia, sold out about 10 years ago, and little remains but the name. Still, the one in the window had the great eagle decal and looked well made, so I took it home in spite of the outrageous price.

And in spite of the fact that our family of five already had six. That seems a ridiculous lot of sleds, but it's my aim to stockpile enough to supply our grandchildren, however many may come along. Right-thinking parents understand that it's not possible for a child to grow up properly without a Flexible Flyer, preferably a five-footer.

I suppose the new Blazon-Flexible Flyer, manufactured in Mississippi, makes some sort of statement about our times. It's not a bad sled, handsome and sturdy as any other sled being made these days; fact, except for the trademark, it's more or less indistinguishable from its compeition. But it's not a Flexible Flyer.

The real FF was the Rolls-Royce of sleds, and like the Rolls was built with fanatic attention to quality and stubborn disregard for the realities of the marketplace. It was designed by men who seemed to believe that the world was full of big fat crazy kids who spent their winters trying to wreck sleds. Not the least of the achievements of my youth was that I did manage to destroy one, and in a single day, without getting it run over by a car, which doesn't count.

Like Rolls-Royce Ltd., the Allen Co. made its product better and better while the economics grew worse and worse, until the bubble burst. But there was no government bailout for the Flexible Flyer, and it's gone.

Well, not actually gone. They may not be making them any more, but it will be some centuries before the last FF gives up the ghost. We have one about 75 years old, that's endured the abuses of three generations of boys and is as sound as the day it came from the shop. It has ornate wood shaping reminiscent of the 19th century and was given to us by an old gentleman of Fairfax who was moving to Florida and wanted it to have a good home. I would take it to the Smithsonian to see if it could be precisely dated, but they would probably talk me out of it. That's how they get their stuff.

Our second-oldest sled, a squared-off model of World War I vintage, is a five-footer that was passed down by my Uncle George, who failed to destroy or even damage it on the hills of Cherrydale. If you don't know Cherrydale and my Uncle George you cannot appreciate this testimonial.

It was a great honor to be given the sled, because he loved it and loves it still. His initials are writ large upon the underside, painstakingly traced with the tip of a hot poker and then filled with pitch.

There seems to have been a hiatus in FF production during World War II, but when the sled came back it was better than ever. In the Korean War era the design was greatly improved: A blunt chrome bumper was added and the rear ends of the runners were turnedup and rivited to the side rails. This not only removed the danger of kids' getting sliced or speared in a pileup, it made it possible to show of by sledding backwards. Piling up and showing off are what sledding is all about.

Three of our sleds are of this model. One is the second five-footer my father gave me and the other two I picked up on the street in Hastings-on-Hudson, New York, where they had been put out for the trash man. I brought them home on a train whose conductor first tried to throw me off the train. After I explained about Flexible Flyers he tried to buy them.

Our sixth FF, another five-footer, apparently came from the final production run. Like the wonderful one-hoss shay, it could not be improved upon, and it probably will last even longer. It is heavier and stronger than any of its predecessors -- although just as flexible -- and has more chrome, finer-grained oak and better steel.

Last year I broke it by jumping a six-foot ramp onto a raised manhole that was hidden under the snow. It cracked two of the three cross-ribs, rendering the sled rather too flexible. I had known it was a fine sled, but not just how good until I set about repairing it last week (to make sure there would be no more snow this winter).

It's easy to make a strong sled and even easier to make a flexible one. The trick is to make it both.

Flexible Flyers are put together with rivets whose heads are precisely spread so that the joints are strong and snug but not rigid. Five-footers have broader and heavier runners than the lesser sizes, and all the other parts are scaled up proportionately. Yet if anything,it's more flexible than the smaller ones, made so by a cunning arrangement that gives the steering bar tremendous mechanical advantage. The fastest and most Flexible of all Flyers was the semi-legendary eight-footer, a monster that could carry an orphanage. I once saw a man killed riding one; he was at the bottom of five men lying prone who went over a 10-foot jump. The sled survived.

The Allen Co., expecting its sleds to be crashed, built the front end with cotter-pinned rivets to make it easy to disassemble for straightening. But to get the cracked cross ribs off it was necessary to drill out the rivets. Then it turned out that the ribs were not only subtly different in shape but of different sizes, none of which was a standard lumber dimension.

The same is true of every other piece of wood in the sled, and of the wood in other sizes and vintages of Flexible Flyers; obviously the quality-control people were allowed to specify whatevey dimensions they thought would add strength here or save weight there. Which means the factory had to either special-order or custom-mill all its oak. And each piece went through several shapings. The craftsmanship and economic arrogance implicit in such hang-the-cost decisions is not of our time, and it's a wonder that the company lasted so long.

The mill foreman at the lumberyard shook his head when I showed him the ribs. "Not worth the time it would take," he said. "What are they from"? "A five-foot Flexible Flyer." "Oh," he said. "Well." He rummaged through his racks of oak, considering this and that plank until he found one whose straightness and density of grain satisfied him. Then he sawed and milled it with all the care of a watchmaker.

"How much?" I asked the man at the counter. "What's it for?" "A five-foot Flexible Flyer." "Take it," he said, putting away his pencil. "That was a hell of a sled."

It took all afternoon to ressamble it. The rivets were nonstandard and had to be replaced by stove bolts with opposing nuts to set the tension. There were no suitable roundheaded nails to be found to hold the slats; brass screws looked good but not right. No amount of jigsawing, rasping and filing would exactly reproduce the original shape of the cross ribs, but in the end it was as strong as new, and nearly as flexible.

I polished and oiled the runners and put it away for other winters and other generations. If I can find half a dozen more Flexible Flyers I'll be almost satisfied.