You probably think you know Firefighter Joseph E. Maloney. Son of a cop; grandson of a fireman; married forever to Kathy, the pretty, tough- talking nurse; father of Joe, 10, and Megan, 7.

Sure, you know Mr. Maloney, 45, of Farmingville, N.Y. He is the tall, dark and handsome type who keeps the muscles pumped and the prankster side buffed. Every firehouse has one -- or a dozen -- like him.

He's driving the Ladder Company 3 truck in Manhattan, spots a yuppie couple sipping lattes outdoors, and blaaatt! he smacks that horn, rattling them and their cups.

And he's wearing a "borrowed" chief's uniform, baby powder graying his hair, haranguing a quivering probie (new firefighter).

You know him? Not at all. Meet Mr. Maloney, who never mentioned fear or death, who cared more about being a hero dad than a hero firefighter, although he was both.

Recently, Mrs. Maloney was going through paperwork -- he was fastidiously organized -- and found a note, stuck between the kids' birth certificates, dated 1995. "Honey, if I die and if on the F.D.N.Y.," he wrote, "you will fare O.K." Tax instructions followed, and an admonition to a giddy shopper: "Don't spend a lot of money." It concludes: "I love you, Joseph and Megan. Sorry I had to leave you so early. Your father and husband, Joseph E. Maloney."