Mr. Hirschhorn, 67, was an Academy Award winner for co-writing (with collaborator Al Kasha, who, like his co-writer pens both music and lyrics) theme songs to the 1970s disaster movies "The Poseiden Adventure" (which boasted "The Morning After") and "The Towering Inferno" (which spawned "We May Never Love Like This Again").
His wife, documentary producer Jennifer Carter Hirschhorn, survives him.
Kasha and Hirschhorn were Academy Award nominated for their score (and the song "Candle on the Water") for Disney's "Pete's Dragon," in 1977.
They also co-wrote additional songs added to the Gene de Paul-Johnny Mercer film score of "Seven Brides for Seven Brothers" when that show was reimagined for Broadway. It was revived earlier this year in a further-revised version by Goodspeed Musicals in Connecticut. A tour is planned.
They also shared book, music and lyric credit for the Broadway musical, Copperfield, based on "David Copperfield" by Charles Dickens. The writers also wrote the books "If They Ask You, You Can Write a Song," "Notes on Broadway: Conversations With the Great Songwriters" and "Reaching the Morning After."
In 2001, the play Musical Chairs, written by Mr. Hirschhorn and his wife, was performed at the El Portal Center for the Arts in North Hollywood, according to the L.A. Times.
Over the years, the Bronx-born Mr. Hirschhorn was also a video-guide author, journalist and (for Variety) theatre critic.
Mr. Hirschhorn studied at the High School for the Performing Arts and Hunter College.
He is also survived by his wife's two sons, Kevin and Brent Carter; his mother, Evelyn Hirschhorn; his sister, Madeleine Desjardins; and a grandson.