SOMETHING HAPPENS to beautiful actresses after they've been in Hollywood too long," said TV producer Mark Carliner. "They seem to lose their freshness."

And so, when it came time to cast women for his TV pilot, "Flying High," Carliner went to New York, where he thinks "the most beautiful women in the United States" reside.

"That's a statement of fact," he said. "The modeling agencies - Ford, Wilhemina, Zoli and Elite - sout the world for beautiful women and bring them to New York. So I let them do the pre-screening.

"For the series I wanted to combined intelligence and personality with quintessential beauty. Then you have a basis on which to build a TV series. I cut the suit to fit the, uh bodies."

Carliner said he began his New York interviews in the Princeton Club, "but the board of directors saw all these beautiful women coming in every 15 minutes and they thought I was pandering." He moved to the Waldorf, where he eventually settled on three models - Pat Klous, Connie Sellecca and Kathie Witt. They were short on experience, he admitted, but they had "the look."

"I wanted three girls who turned me on as a man, but who were also not threatening to women. I was hoping I'd have not one Farrah Fawcett-Majors, but three - three separate looks."

Carliner then took his prospective stars to the network. "Yeah, like visual aids," said Pat Klous, imitating Carliner's pitch to the programmers: "Now this is Pat and she will put a few streaks in her hair and be just a little lighter, and this is Connie and she'll be the sexy one with long hair, and this is Kathie . . ."

"I had to overcome the shibboleth that models can't act," Carline explained. "That's the prevailing philosophy. So I thought I'd show them. I'd bring the three girls with me and have them read 25 minutes of the script.

"A funny thing happened on the way up to [CBS vice president of program planning] Harvey Shepard's office. We were in the elevator with the network sales head. He saw me with these three beautiful women and asked what we were doing. I said, "We're going up to try to sell a TV series. 'Do you know that by the time we got to the 31st floor of the building, the network sales had called the head of programming and said, 'We need this show.'"