C.D.B. Bryan's career began when "I was booted out of Episcopal High in Alexandria for cheating in a Latin examination. I wrote a story about it, and it was my first sale to The New Yorker."

After growing up "more or less" in the Washington area, he was drafted and sent to Korea, where he "first encountered the abuse of human beings that started me on the track to writing 'Friendly Fire.'"

A seasoned professional with countless magazine articles and four books to his credit, Bryan, 43, now lives in Guilford, Conn., "in a rented cottage deep in the woods at the end of -- no kidding -- Podunk Road.

"It's only an hour and a half from New York, and there are universities nearby where I can do the writer-in-residence routine when I run out of money, which happens semi-annually."

It was as a writer-in-residence at the University of Iowa that he began "Friendly Fire," a book about an Iowa mother's bewildered and ultimately militant reaction to her son's death in Vietnam. Bryan's personal life was woven into the book's final draft and into the television adaptation earlier this year -- including hints of his marital problems in Guilford.

"I originally settled there because I fell in love with a particular house.

It was a big place and my family was growing -- at least I thought so. It was suddenly reduced through divorce, so I sold the house and now I have the cottage."

"There are about three weeks every year when it is a pure joy to live there, and this is one of them," says Bryan. "So what am I doing on the road?"

What he is doing is promoting his new book, "The National Air and Space Museum," published by Abrams, a company that specializes in expensive art books and does most of its business between now and Christmas.

Isn't that a change of pace from his "Friendly Fire?" "It sure is," says Bryan, a wide grin breaking out above his red, polka-dot bow tie, "and a very nice one. Nobody ever said I couldn't write a book that's fun once in a while."

Bryan has never piloted an airplane except in fantasy life, but he has flown dozens there. "I remember," he says, "in my childhood some kids were interested in steam engines and some in fire trucks. I liked airplanes.

"I used to read the old pulp magazines about World War I airplanes -- printed on paper so bad it had already turned brown by the time you got to read it: 'Wings' and 'Flying Aces.' The hero always had steely blue eyes that fixed his target in the gunsights -- rat-a-tat-a-tat. There was lots of rat-a-tat-a-tat."

Bryan was hired for the NASM project because of his reputation as an all-purpose journeyman writer -- one who could write to fit the prose between the pictures which are the book's major attraction. But he was a fan of the place long before it become an ultra-modern repository of spacecraft and the busiest museum in the world.

"I started going to this place," he recalls, "when it was a Quonset hut next to the Castle. Now it's attracting 10 million people a year. You know, in the days, Lindbergh used to slip into the Smithsonian incognito and just stand and look at the Spirit of St. Louis, and nobody recognized him. It was a lot less crowded then."

Along with a mania for airplanes, a mania for writing stirred early in young Courtlandt Bryan. (He uses the initials because people have so much trouble with the name; his friends call him "Courtie.") He inherited the writing talent along with the name and a deluxe entree into the field of magazine journalism. His father, J. Bryan III, was a writer for Fortune magazine, and editor of The Saturday Evening Post and is the author of several books, including one just published, "The Windsor Story."

"I bought his book at a discount," says Bryan, "and I think he's getting a discount on mine. But what is a father for if not to buy your books?"

The next book for his father to buy will probably be a novel -- a form to which he is returning after two nonfiction books. In the mid-'60s, he recalls, "my first book was a novel, which encouraged me to write a second novel, which discouraged me from writing a third. You tend to put everthing you know into the first novel, and then you rewrite it for the second.

The third one will be about how men's and women's relationships have changed -- or should have changed -- in the last 10 or 15 years. When a woman in the story asks a man, 'Would you want a man to treat your daughter the way you are treating me? it should have some very strange overtones."

So far, he has written 150 pages of the new book and discarded them -- but that is fairly standard procedure. "In the first year of work on 'Friendly Fire,' I wrote 900 pages and then threw them all away. They just weren't right.'

Rewrites were not the only problem he had with books. There was a much-publicized disagreement with Peg Mullen, the determined mother in the story, over whether it should be told his way or hers. And he recalls that the people in Guilford ("really a Norman Rockwell kind of village") "gave me a lot of flak when my book was published and began making the front pages."

In contrast to "The National Air and Space Museum," for which he produced 80,000 words between September 1978, and last May, the rate of usable production for "Friendly Fire" was "about a paragraph per week, not counting what didn't get into the book."

He still seem slightly uncomfortable talking about it -- happy to be in the more friendly skies of the museum. "Theoretically," he says, "that was supposed to be a New Yorker piece -- about 6,000 words -- and it just ran away."

A few hours later, at a cocktail party held at the museum to celebrate the book's publication, Bryan was clearly in his element. He wandered around, staring at the exhibits he had seen so often before and written about -- still fascinated by the "Spirit of St. Louis," the Wright Brothers' original aircraft, an X-15, a duplicate of Skylab, and one of the museum's more recent acquisitions, the "Gossamer Condor."

"That's an amazing craft," he said, looking up at the enormous, transparent one-person plane that won a $95,000 prize two years ago as the first aircraft powered by human muscles. "That wingspan is 96 feet," he said, "and it only weighs 70 pounds. It was designed specifically to win that prize, and they had a lot of fun doing it."

Chatting with him were former astronaut Michael Collins and publisher Ian Ballantine, who originated the idea of the book and persuaded Andrew Stewart, the president of Abrams, to publish it. "Are you Michael Collins the former astronaut?" a partygoers asked. "No," he replied, $ i'm the real Michael Collins."

Ducking outside for a quick cigarette, Bryan recalled how he got the assignment to write the book: "I saw Ian in Chicago while I was pushing 'Friendly Fire,' and we got to talking about museums. I told him, 'You know the museum I really like -- Air and Space,' and he asked me, 'How would you like to do a book?'

"It was really a hired-gun job -- I was going through a divorce, and I needed the money."

Asked how he felt seeing himself portryayed on the screen in "Friendly Fire," by said he found it "impossible to respond intellectually. It's very strange to see Carol Burnett put arms around an actor and say, "Hello Courtie.'"

In the background, pianist Bruce Steeg matched the Air-and-Space theme of the evening with a series of carefully chosen melodies such as "Fly Me to the Moon," "Blue Skies," "When You Wish Upon a Star ," "How High the Moon" and "Over the Rainbow." Little knots of fans gathered around Bryan to chat about the problems of writing a museum book that would not read like all other museum books (". . . so I told him look, general, I have this much space to fill and I need three funny anecdotes about space pilots. . .")

"I love your party room," said one departing guest, and Bryan smiled at the one-of-a-kind decor for his reception -- obviously wondering where he would ever find another subject like this for a book.