Fox's new prime-time TV season is now officially a train wreck.

Yesterday the network canceled its entire Friday lineup and will punt with feature films and schlockumentary specials on that night, which is just another in its growing lineup of ratings disasters.

Gone immediately are Chris Carter's high-profile drama series "Harsh Realm"--for which Fox gave Carter a firm 13-episode commitment at about 2 million bucks a pop--and the Gen-X cop show "Ryan Caulfield: Year One," which in Hollywood circles has been unofficially renamed "Ryan Caulfield: The Two Episodes."

This Friday, the network will air two lowbrow specials: Think "World's Most Shocking Moments." And, during the November sweeps race starting next week, Fox will fill the two-hour hole with feature films from its library, including "The Nutty Professor," "Happy Gilmore" and "Jumanji."

The plug was pulled yesterday afternoon, after Nielsen delivered the sorry news that last Friday, Fox had scored just 3.3 million viewers--its smallest audience ever on the night with original programming and barely ahead of WB and UPN.

Specifically, Carter's new sci-fi series, which had premiered with a none-too-pretty 7.5 million viewers two weeks earlier, dove to 3.7 million. And "Caulfield," which had premiered one week earlier with 4.4 million viewers, plunged to 3 million.

But why should Friday night be any different from the rest of Fox's prime-time schedule, which has turned some of the season's most anticipated new shows into some of broadcast television's most spectacular disasters?

That includes one show, "Manchester Prep," that was canceled before it ever aired because it was just too awful. And how about "Action," the hottest new show of the season, which last Thursday plunged Fox into sixth place at 9 p.m. Thursday night--behind even WB's "Charmed," UPN's "WWF Smackdown!" and ABC's just canceled "Wasteland."

Then there's last season's hit, the animated sitcom "Family Guy," which Fox managed to kill off in just a few Thursday broadcasts.

Fox has yanked the show and will try to resuscitate it in a different time slot because Fox produces and owns the show and has a pricey deal with its creator and executive producer, Seth McFarlane. Sources say the show is also being retooled and that Fox execs want to bring in some of the folks from "The Simpsons" to run it, taking 25-year-old McFarlane out of the driver's seat.

Fox's season start is so bad that it's making last season's start look good, and last season's start got the head of Fox's Entertainment division fired.

Here's the lay of the landscape over at Fox: Tuesday, down 31 percent; Wednesday, down 20 percent; Thursday, tacky specials that attract men like maggots have kept the drop to 6 percent; Friday, up a tick despite "Harsh Realm" and "Ryan Caulfield," thanks again to schlock specials; Saturday, down 32 percent; Sunday, down 26 percent.

Not surprisingly, Hollywood's TV community spent some time yesterday circulating a rumor that Fox's new Entertainment chief, Doug Herzog--the guy who replaced the guy who was fired last November--was not long for the job. Fox vehemently denied the rumor.

But, as of yesterday, Herzog had one more night's programming yet to debut. Last night was the premiere of Fox's "Party of Five" spinoff, "Time of Your Life," and the season debut of "Ally McBeal," with its much anticipated sex-in-the-car-wash scene.

And, speaking of the kaput "Wasteland," its cancellation leaves ABC with a one-hour hole in its Thursday lineup and the November sweeps race bearing down. The first Thursday of the derby, Nov. 4, the Disney-owned network will venture deep into Fox territory with a special called "Totally Out of Control Vehicles." The following two Thursdays, the network will double-up broadcasts of "Whose Line Is It Anyway?" and "Who Wants to Be a Millionaire?"

CAPTION: "Harsh Realm," with Scott Bairstow, top, and Ryan Sean Maher's "Ryan Caulfield: Year One" are casualties of Fox's abysmal ratings.

CAPTION: Fox Entertainment's poor Friday night ratings may cost President Doug Herzog his job.