Actually, the Credit Goes ‘Back & Forth’ : Pop music: As a teen-ager, Aaliyah already has a Top 5 hit. But she knows how much it helps to have R. Kelly doing all but the lead vocals.

Just how did an unknown Detroit teen-ager like R&B; singer Aaliyah score such a smash hit with “Back & Forth”--her first ever single?

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You could say it’s so good it simply rocketed into the Top 5 on merit--but that’s not the real story.

Aaliyah’s “Back & Forth” is a fixture in the pop Top 5 partly because of R. Kelly, one of the hottest artists in the business since his “12 Play” album sold more than 3 million copies. He not only produced and wrote “Back & Forth,” but he also does the rapping.

Getting airplay for a single by a new artist is tough--unless it features R. Kelly doing everything but the lead vocals. Fans love just about anything he does, and “Back & Forth” is the next best thing to a new R. Kelly single. Also, Aaliyah’s debut album, “Age Ain’t Nothing but a Number,” jumped into the pop Top 20. That R. Kelly connection--he wrote and produced the collection--is a major factor in the album’s success too.

Does Aaliyah (pronounced ah-LEE-yah) get testy at the suggestion that she has soared to fame on R. Kelly’s coattails?

Not really.

“I know having him on the single helped it get attention,” says Aaliyah, whose last name is Haughton. “Without him it would have been harder to get airplay. I’m just thankful for the break. If I had no talent and had nothing to offer, I’d probably feel funny if people were giving him all the credit. But I know I can sing and a lot of the success is because of me.”

There are two sides to Aaliyah. On the one hand, she has the image of a streetwise tough girl who could easily pass for 20. But then there’s also the genteel, ladylike 15-year-old who’s majoring in dance at the Detroit’s High School for Performing Arts.

So which is the real Aaliyah?

Because that soft-spoken, sophisticated side of her is so dominant, you get the impression she’s not really a street type.

“What’s the real me--it’s hard to say,” she says in a telephone interview. “I have a feeling for the hard-core street life, but I like to hang out in malls. I’m definitely going to college, and I’d like to get a doctorate in music history, with a minor in engineering. But I love singing more than anything. What does all that say about me?”

Aaliyah has been dreaming about a show-biz career ever since she was a youngster. “I’d sing at the drop of a hat,” she says. “I did some performing as a kid and I loved it. I had great feeling for it. I had it in my mind that’s the career I wanted.”

It helped her show-biz aspirations to have an uncle, Barry Hankerson, who’s an artists’ manager. A few years ago, he became R. Kelly’s manager too. Now he’s also her manager.

“I signed her about four years ago, long before I met Robert (R. Kelly),” he explains. “When she was about 10 or 11, I took her to Warner Bros. and MCA Records. They liked her singing, but they didn’t sign her. Robert was impressed too when she first sang for him. She sang a cappella, and he said she has perfect pitch. He decided he wanted to work with her.”

Jive Records, also Kelly’s label, signed her two years ago. The tough part about making this album was Kelly writing from the point of view of a 15-year-old female. “He just spent time with me, trying to see how I thought about things and what people my age think,” she explains. “It may seem funny for him to do an album like this, but he has ideas about different things that he can’t use on his albums.”

Since they started the project, the question she’s most often asked: What’s a nice girl like you doing with a seeming rogue like him?

“People ask me if my parents mind me working with someone like him,” Aaliyah says. “But they’re thinking about the guy they see on stage or the guy who makes those sexy albums. But that’s his stage image. It’s just one side of him--not the side I see. He’s really a sweet guy.”