Heads up!

Pieces of subway track have fallen from Bensonhurst's elevated line onto 86th St., cracking car windshields and nearly hitting pedestrians, residents and merchants charged.

"It's not just irritating, it's dangerous," said Hilna Tires manager Louis Gellman, whose shop is underneath the D train el at 86th St. and Stillwell Ave. "Does one of the trains have to fall off before they say, 'I guess we should fix that?'"

Mechanics at the auto repair shop have collected several metal pieces that have plummeted to the street in recent months.

Their collection includes a twisted piece of metal that landed on the pavement on Saturday and a rusty spike that hit the roof of the company's van last month, cracking the windshield.

Mechanic Al Vaccaro had a close encounter with an airborne object that fell just a few feet from him as he crossed the street several weeks ago.

"It could put a hole right through your head," said Vaccaro, 61, of Mill Basin, who joked that he may start wearing a hard hat.

Home improvement contractor and nearby resident Robert Levy, 50, saw a metal piece fall when he left the 25th Ave. station about two weeks ago.

"Thank God it hit no one," said Levy, who lives on nearby Bay 37th St. "It's horrible. How can you have this? There are a lot of people who walk around over here."

A Metropolitan Transportation Authority spokesman said workers have found debris on the street under the el in the past, but insisted no complaints had been filed about Saturday's incident.

"The people who run the auto body shop have had some problems from when there was a crane there months ago," said MTA spokesman James Anyansi. "When someone has a problem, they should take a picture and file a report."

The MTA installed new tracks along the crumbling viaduct last year and has continued rehabilitation work in the area.

That work created an earlier problem when Gellman and other merchants complained in January that trains made ear-splitting noise when they passed on the new overhead tracks.

The possibility of getting hit has forced local delicatessen manager John, to avoid the el altogether.