On July 28, 1945, an Army B-25 bomber crashed into the fog-enshrouded Empire State Building. It was a bizarre incident that momentarily pushed the bulletins of World War II action off the worlds front pages.

Joining the 25,000 other New Yorkers who kept a vigil that rainy Saturday morning was 10-year-old Arthur Weingarten. As he strained to see the 79th floor where the twin-engine plane had hit, sending flames up to the 86th-floor observation deck, and watched ambulances carrying away the first of the 13 people killed in the accident, that morning became a part of Weingarten. And now a reconstruction of that morning has become his first book, "The Sky Is Falling."

"I saw the stretchers and knew this was real, real death. The war was going on but right in front of me were charred bodies you couldn't identify. That was the holocaust I saw," recalls Weingarten.

In his book, personal ironies - the priest who stopped for a shave and so missed the plane when it came through the windows of his destination, the Catholic War Relief Services office - overshadow the actual disaster. One of the curious twists is that Weingarten happened to be at City Hall that with his father, a fire marshal, when Mayor Fiorello La Guardia got the news of the crash. Father and son rode to the scene in the mayor's motorcade and were able to observe peoples reactions close range.

For 32 years the sounds and odors of this tragedy stayed with Weingarten. For some years they formed a recurring nightmare. Eventually suppressed, it all came back, Weingarten says, during a session on dreams with his analyst. Yet the awesome spectacle and its toll on human emotions was never as vivid as during the last two years of research for the book.

"I don't know why the survivors and the eyewitnesses talked to me and not other writers. Martha Smith, the widow of the pilot, had a list of 30 requests from over the years'" says Weingarten, bewilderment and oneupmanship showing in a voice that's still more Brooklyn than his adopted Los Angeles. "Maybe," he adds, just enough time has passed."

Timing was as important for the author as it was for the key characters. While a teen-ager in New York, Weingarten entered show business, as a regular on the radio show, Juvenile Jury, then on the television show, "Youth Wants to Know." In his neighborhood, he edited a newspaper, The Flatbush Courier, and then won a photography contest, with a picture of the United Nations, Building, that enabled him to spend a summer at Life magazine. His family steered him toward pre-med studies at New York University but he spent his summers with summer stock.

Eventually he wound up in television and over the last 15 years his name has been in the credits of more than 500 television shows, both as a writer and producer.

"Then," he says, swinging his leg over his chair, "I was almost 40."

"I was the producer for an NBC show called 'Archer' and we were canceled. I had 36 weeks left on my contract, and I told my wife I didn't want to go back to the network, sit around and go to meetings. We didn't need a vacation. So what I wanted to do was write a book." The idea was not new to his wife but the subject was.

"I had never discussed the crash with her. And she said, 'That's the worst idea I've ever heard in my life, who cares about death, dying and catastrophe?' My best friend said 'that's one of the best ideas ever, just do it from the people, not the disaster angle.' I did."

At times it was an emotional experience. When Weingarten found Mrs. Smith, the widow of the pilot who had flown 50 combat missions in the war, she started to cry. "She wanted to know how I found her telephone number and why I wanted to talk to her. I told her I wanted to do an account like the Bridge of San Luis Rey," a story of plain people getting up one day, going to work, and then, disaster," Weingarten recalls. When Smith, who has never remarried, agreed, she ended up crying during the interview. And when she read the published book, Weingarten says, she cried again, saying that she finally knew all the answers to the questions she had been afraid to ask.

"I was constantly confronted on two levels during the research. My 10-year-old self, feeling childish, talking to people of another time and place," says Weingarten.

"And," he says, "I thought about my own mortality a lot. While doing a film in North Kenya a few years ago, I had contacted malaria. One of the side effects is the shakes. And when I started interviewing people like Martha Smith they reoccured. She would talk, I would start sweating. She ended up taking care of me."

Besides interviewing 200 people for "Sky," Weingarten says he tried to get the official Air Force report of the crash. He was told by the Air Force that the records had been destroyed in the 1973 fire at the General Administration Services Center in St. Louis.

"Well, I didn't believe that because the government doesn't keep just one copy of anything," says Weingarten. Finally a source furnished him with a copy of the report and a folder of correspondence related to the incident. In the file, Weingarten says, was a letter turning down a request from Sen. Barry Goldwater for the same material. "I don't understand their reluctance," says Weingarten.

Quite expectedly, the movie makers are examining his book. There are enough stories and ironies to attract a roster of stars: the plane's crew chief who hadd escaped from the Germans in Holland: The Navy machinist who begged a ride to go home to console his parents who were grieving over his brother's death in the Pacific; the elevator operator singing "The St. Louis Blues" as the plane severed the cables; and another elevator operator who was leaving the job that day to rejoin her Navy husband. And Theresa Fortier Willing, one of the survivors from the Catholic War Relief Services office, where the plane hit, who threw her ruby ring out the window because she thought she was going to die. A few days later it was found and returned to her. Willig has been in the news lately because her son, George, recently scaled the World Trade Center.

It's enough for nay screenwriter but Weingarten doesn't want any part of a movie. "I am not going anywhere near it. I will hope for the best," he says.

What he wants are the stories of spunk, rather than the spiraling flames and cries that will probably domiate a movie treatment. Stories of courage like that of Mary Scannell, the elevator operator with the heavy Irish brogue, who has undergone 16 skin and bone graft operations, and is now an operator at the United Nations. "She said 'I guess we were both involved, so let's talk.' She's a real hero."