Two months from now Kay Richardson, belly dancer, will try to stump the panel of "To Tell The Truth." It should be no problem since everyone knows belly dancers are darkly attractive women with intriguing accents and Kay Richardson certainly is not. She is a blue-eyed, 26-year-old blonde with the healthy good looks of a Texas cheer-leader and the credentials of an urban transportation consultant. Which she also is.

"I'm just fascinated by freight transportation," she says, and her Princeton master's thesis on the subject proves it.

But her passion is belly dancing, or Oriental dancing, and she is so good at it that audiences shower her with money and cheers (once an obese sheikh from Abu Dhabi threw himself on her while she was performing an elaborate backbend), and she has become a Washington favorite a charity auctions. A Chase Manhattan vice president recently bid $350 for her services at a Corcoran art school benefit, a bit higher than her normal $200 fee for working parties.

Richardson says she "went bananas when I heard my first Arabic record" in Greenwich Village about three years ago, and "I said to myself, 'This is it - you know how to dance to this.'" She finished at Princeton in 1975, but quit a full-time Department of Transportation job a couple of years ago to consult and (more to the point) to dance.

It's been nonstop boogie ever since, about three hours a day in her Adams-Morgan apartment, sometimes nude, sometimes wearing hand-made, heavily beaded costumes.

Is this daughter of an Air Force officer, this former coed at a Texas junior college, any good as a belly dancer? Middle East natives say she ranks with Cairo's best. And several years ago, before she quit performing at area clubs, she says jealous dancers sometimes sabotaged her act by burning her costumes.