This is a rush transcript from "On the Record," February 18, 2010. This copy may not be in its final form and may be updated.

GRETA VAN SUSTEREN, FOX NEWS HOST: Fun, normal and regular -- that is how pilot Joe Stack's good friend describes him. But think about it. That same normal guy within a couple hours posts a ranting anti-government manifesto, lights his house on fire and then flies his plane full throttle into a building filled with federal workers. So just who is pilot Joe Stack?

Billy Eli was bandmates with pilot Joe Stack. He has known him for years. Bill joins us live in Birmingham, Alabama. Billy, how did you meet the pilot?

BILLY ELI, LEAD SINGER, BILLY ELI BAND: He showed up at an audition. We were looking for a bass player, and a friend of mine said, Hey, I know somebody. Want to give him a try? And I said sure.

VAN SUSTEREN: During the time -- how many years have you known him?

ELI: About five-and-a-half, maybe six.

VAN SUSTEREN: How did you learn about what happened today in Austin?

ELI: My wife called me and said, Hey, there was a plane crash. And at first, she didn't know it was Joe. And then I started to get telephone calls from people that knew I knew him and said, Hey, did you hear? And I called home, and you know, the things kind of snowballed since this morning, obviously. And that was how I found out, so...

Watch Greta's interview

VAN SUSTEREN: All right, obviously, one of the things that developed this afternoon was the fact that he posted on the Internet this manifesto that was, you know, a rant against the United States government, the IRS. Did you -- is that -- is that the Joe you knew?

ELI: The Joe Stack that I knew was mostly apolitical. I never heard him take a political stance either side, left, right. As far as I know, he didn't have a party affiliation. Let me say that my relationship with him was mostly based on us being bandmates. And we socialized together from time to time, but like, I wasn't one of his regular co-workers or somebody, you know, that -- I didn't see him every day, just when we had band functions. And I considered him a friend of mine, but I didn't know that much about, you know, his political life or anything like that.

VAN SUSTEREN: In searching your mind now and going back over your relationship with him, is there anything that stands out that you think now, like, you know, Boy, that was really weird about this guy or that was a sign? Anything strange about him?

ELI: Well, that's the thing about this that's been so shocking. No. I mean, he was, like, a normal, right down the middle kind of guy. And I mean his personality. He wasn't introverted. He wasn't extroverted. He - - he, you know, was kind of engaged. He knew a lot about a lot of stuff. He was fun to work with musically, solid bass player. I played with him about three years. We, you know, made a number of recordings together. And so yes, this -- I'm still in a kind of a state of shock, you know? I'm trying to kind of compartmentalize this and process it.

VAN SUSTEREN: Do you know his wife and the child?

ELI: I do.

VAN SUSTEREN: And where -- how long has he been married to her? I think this is a stepchild, is that right? He's married -- the -- this is not his child?

ELI: That's correct. They've been married a couple of years. And you know, I hadn't seen the manifesto or anything. I have no idea what it says. I've heard about it, of course. When I knew Joe, he was genuinely happy being married and being a father, so...

VAN SUSTEREN: What does his wife do for a living? Is she -- she's not a stay-at-home mother or something? Do you know anything about the wife?

ELI: She's a musician and a music teacher.

VAN SUSTEREN: Any idea why she wasn't home at 9:00 o'clock this morning? Had they split up? Was he going through, you know, a broken relationship?

ELI: No, I couldn't -- I can't speak to that. I don't really know.

VAN SUSTEREN: And there's nothing else, there's nothing sort of -- as you search your mind, there was nothing peculiar about this guy? This is just, like, a, quote, normal, regular guy, and then one day you hear he's run a plane into a building.

ELI: Right and -- exactly right. You know, this was obviously a facet of him that he had, but I knew nothing about this. I never saw this.

VAN SUSTEREN: Billy, thank you.

ELI: OK. Thank you.

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