(CBS News) NEW YORK -- New York City has been attacked by terrorists in the air and on land during the past 20 years. It's still considered the number one terror target in America.
And one of the biggest potential threats is an attack by sea.
But the newest tool designed to protect New York is a specially outfitted helicopter.
As the Bell 412 chopper approached an airfield in a remote corner of Brooklyn recently, everyone came out of the police hangar to see it land.
The brand new $10 million dollar craft was being delivered from the factory in Tennessee.
It's loaded with $4 million worth of hi-tech equipment, and part of its job is to keep a nuclear bomb out of the city.
The new New York Police Department chopper is equipped with new radiation detection equipment so sensitive that it can fly over a container, cargo or tanker ship and accurately detect a radiation signature from an altitude of 200 feet.
"The nice thing about the aerial capability is you're more mobile," says Lt. Art Mogil, of the NYPD's counter-terrorism division. "You can hit more different areas, and hit it faster.
"So, we've done some research, and we've worked at kind of best-of-class. And I think we've come up with a very robust system that has a very large sensor array."
The very latest tool in the city's counter-terrorism arsenal is another sign of how critical helicopters have become in the counter-terrorism operations of the nation's largest police department.
"We're looking at the critical infrastructure of New York City," said Capt. James Coan, of the NYPD Aviation Division. "The symbolic buildings -- is there anything out of place? Anything suspicious? Anything we didn't see the day before that now has changed and will require investigation?"
A normal police helicopter patrol might focus on commercial areas, looking for burglars on a rooftop, or over the water for a rescue. But the counter-terrorism patrol, executed several times a day by the NYPD, takes them off the beaten path.
The types of things they look for that would set off alarm bells include "small boats that shouldn't be there, maybe with unusual activity, numerous people messing around or something they shouldn't be doing, (something that) looks unusual," says pilot Bill Lapaugh, an NYPD Aviation Division detective. "We've got a few pipelines we also check."
Every day, they also patrol the Buckeye Pipeline. Like much critical infrastructure, most New Yorkers don't even know it exists, but 10 million gallons of fuel travel through the pipeline to airports and fuel distributors each day.
In 2007, three men were charged and later convicted in a terrorist plot to blow up the pipeline.
"The mission has changed rapidly," Capt. Coan said. "And we now are 360 degrees, and aviation is being used more as a force multiplier. Not just for patrol, but for intel, counter-terrorism, and the detective bureau."
Yet, with all the thoughts of Armageddon, nuclear attack, crashing the city's power grid or blowing up fuel lines, a water rescue call came in when CBS News was on-board.
The pilots pushed the throttle and the divers that ride on-board suited up.
It was a wind surfer who was blown too far from shore and couldn't get back.
Within seconds, the Coast Guard and NYPD harbor units were there to fish the man out. So Aviation 14 went back to its counter-terrorism mission, looking for bigger fish.
To see John Miller's report, click on the video in the player above.