He is 73 and alive, still. That itself is an accomplishment for him. It is not simply his age that tempts the ill-favored odds. That would be too easy.

Karl Wallenda is 73 and still struting across wires strung between hotels, still walking across the high wire at the Tangerine Bowl. But there were those in his family who were not quite so lucky - not by a long shot when they tackled the long shots.

Is entertainment that important?

"Oh yes, you do it for entertainment." He cocks his head thoughtfully. "But in one way you like to be somebody. You know how beautiful it is?"

He parts his hands for emphasis. "I stretch my hands, and then they all stand up and applaud. It's something deep in your heart."

The voice lowers as he leans forward: "You know - you have to face reality. You can go on an airplane and die, after all. We all want to achieve - something."

He smiles politely, a trim, drapper man in a three-piece suit, with the erect bearing and stern, thin-lipped features of a Junker. Throughout the interview, he will keep glancing at his watch, fearful that the place destined to take him home to Sarasota, Fla., will surely leave without him. Througout the interview, producer Daniel Wilson will have to keep reassuring him. The airport is close, they have time.

But still Wallenda fears calamity, or at the very least, a lack of precision. The Germany he left so long ago is still very much with him. The accent and syntax pure Hamburg after all those years: the act, pure ham because of all those years.

"I am very conscientious," he admits, "I can't sleep all night if I miss a call."

Then he gets back to business

"Fifty years ago, April first, I'm very proud to say," he says gloatingly, "50 years ago we was headline in the greatest shows. And also in the greatest vaudeville show - that was Radio City Music Hall.

"We was the first act to open it up." (Along with Ray Bogler and Jan Peerce, whom he neglects mention.)

Karl Wallenda is, above all, a first-billing showman, the kind of entertainer people love to make movies about, since he is the living reinforcement of all the cliches so dear to the heart of show-biz: The-show-must-go-on; Smile-through-your-tears; It's-in-the-blood.

As it happens, Daniel Wilson has made a movie about him, and you can see 'The Great Wallendas" (Sunday night NBC): no Karl in sight, but a whole lot of Wallendas performing their ill-fated pyramid act (and stuntmen tumbling when it topples); Lloyd Bridges as Our Hero, Cathy Rigby and Britt Ekland.

As it also happens, showmanship is in Karl Wallenda's blood, and he has imparted the fever to his own future generation.

"My father and my father's family were in the circus.

Blithely, he ticks off his antecedents. My grandmother was a prima ballerina in Munich, and my mother was more in the theatrical business. But I have aunts what worked with lions and tigers.

"But no high wire. High wire was not in the circus then. When I was a little kid I have to do everything. When I was [WORDS ILLEGIBLE] on a clown costume. But my mother - she trained me to handstand which brought me to the biggest achievements I ever made. I never walked high wire until I was 16. I was the family instigator on the hire wire.

"I said to my brother - who was four years older than me - I said, 'Herman, you want to learn high wire? Good! Then I'm the boss.'"

He grins, pleased with himself. "I came to the U.S. because I wanted to see cowboys and Indians."

A chuckle, "I thought in one year going to get rich. After first year I owe [WORDS ILLEGIBLE]

But over the years he assembled a sensational amalgon of flying limbs, courtesy, for the most art of his extended family sons, daughters, nephews, in-laws - the works. Those who directly related seemed to have a penchant for wedding other acrobats.

"This is what I can't understand myself." Wallenda shrugs, not entirely displeased.

"My grandchildren I chased them off. Yes, I chased them off. But they come back. Trouble is, they start with me and when they got enough they go on their own."

Another grin.

"They want too much money, so they go on their own."

The old face grows solemn.

"One of my daughters is retired; my son is paralyzed. One of my other daughters is now swaying on the high pole, which is even more dangerous. Some step out. But -" a proud lift of the shoulders - "But they always come back you know. Yes, they always come back."

Not Wallenda's wife, though. In 1960, Helen Wallenda retired permanently from Wallenda troupe. Once again her husband is asked why.

He shakes his head, perplexed "This is a question. you know, I never asked her about this."

A pause.

"My wife is too old."

How old?

"Well - " he grins sheepishly - "She is five years younger than me."

It is of course entirely possible that his wife might have considered that specialife de la famille - the impossible human pyramid assembled on the high wire - a bit too . . . impossible for her taste. And it is also possible she may have made a wise decision.

Because in 1962, as Wallenda troupe was once again constructing its seven-person an pyramid on the high wire before an entranced audienced of 7,500 at Detroit's Shrine Circus, Wallenda's nephew, Doeter Schepp, suddenly screamed, "I can't hold any longer!" And so the Great Pyramid collapsed in a fall that killed both the nephew and a son-in-law, and crippled Wallenda's son, Mario.

Karl Wallenda ponders all that now. "I think about still and I don't know how it happened. I still do not know. The seven-person pyramid is never the hardest, but it is the most dangerously. Because - " he raises one finger," - if one man makes a little mistake, you're all dead.

"Herman and I - we was in the worst position, and survived. I couldn't believe it. I said 'There must some angel watching.' I still want to find out why the boy fell. I still want to know."

He shakes his head and continues, dully and without infection. "For about two or three years, I was very numb. I had fun at all. I had almost gone zomble - you know?

"I tell you, after the big accident, then I wasn't interested in the high wire. Only interested in existence for my whole family. My daughter - she lost her husband - who was going to take care of her? Let's say that I had a one-track mind. To make money to pay for those people."

But that was not to be the end of it. In Omaha, 13 months after the Detroit tragedy, a sister-in-law fell to her death from 60-foot swaying pole. A nephew quit.

In 1972, in Whelling, son-in-law touched a live wire and fell 60 feet to his death.

The great pyramid stunt was discountinued, after 1963, resurrected only for the NBC movie. And not so long ago, while rehearsing for that movie, Karl Wallenda, himself, fractured a vertebra in his neck.

"Don't worry about that," he says cheerfully, after all, he walked the high wire in Orlando with a neck brace.

But then he is known for that - for picking himself up, dusting himself off, and doing it all over again within one or two days: after Detroit, after Wheeling, (in that last instance saying only. "I don't feel like walking today. You know why.").

Now he says, his voice gentle on quiet, "This is a big pain when you see people die. Only God can tell you why."

So why not retire?

"I tell you I'm thinking, if I retire, I'm a very worthless man," he says firmly. "As long as you have physical health you should not retire. because you might as well be dead."

He is asked if he keeps to a special diet. He looks stunned - then delighted.

"Yes." Karl Wallend crows gleefully, "Two martinis. Every day, two martinis."

He glances again at his watch, glances back more significantly at the producer, who nods his head. Yes, it is now time to leave.

"How did I do?" he asks the producer.

Fine, Wilson comforts him. Your interview went fine.

I'm a showman," Karl Wallenda explains helplessly.