It should have surprised no one that the FBI has a secret fleet of spy planes it uses domestically to watch us, as the Associated Press reported this week. WIRED published a story about surveillance aircraft spotted flying in unusual patterns in California and Virginia back in 2006. And the Wall Street Journal reported last year that the US Marshals Service has surveillance planes that use so-called "dirtboxes" to track mobile phone users on the ground.

But long before this, the New York Police Department had a high-tech surveillance helicopter that it obtained in 2003 through a government grant and exposed publicly to the media that year when it gave journalists a tour of the $10 million toy.

WIRED began investigating the chopper in 2008, and uncovered, but hasn't published until now, information about the precise surveillance components installed on it and the methods the NYPD used to conceal its ownership and operation. Like the FBI, the NYPD used a shell company to register the aircraft. But the NYPD also requested special "undercover" registration handling from the FAA to thwart tracking by aviation enthusiasts who might spot it in the air and attempt to investigate the registration number associated with it. The NYPD also asked the FAA to notify its aviation unit if anyone contacted the agency inquiring about the aircraft.

This raises serious questions about how many agencies are operating them in the US and how exactly they’re being used.

Last month, the issue of secret law enforcement aircraft began getting attention after plane spotters around the country began reporting suspicious aircraft registered to shell companies that were flying unusual routes over numerous cities. The Associated Press caught on to the stories and this week published its own piece identifying some 50 surveillance craft that were registered to more than a dozen shell companies and were being used by FBI field offices around the country.

The response to that story has been mixed. Some readers were shocked by the secret flights and Big Brother surveillance; others scoffed at the alarm the AP appeared to be inciting, arguing that spy planes are just another surveillance tool law enforcement uses to monitor suspects in areas, or for lengths of time, they couldn't otherwise monitor through conventional means by foot or car. For example, authorities used a special surveillance helicopter with thermal imaging equipment in 2013 to spot the Boston Marathon bomber as he lay hidden beneath a tarp covering a stored boat.

But regardless of the utility of high-tech surveillance aircraft, their use raises serious questions about how many agencies are operating them in the U.S. and how exactly they're being used and to what end.

The AP story didn't provide much detail about the technology aboard the FBI planes, other than to note that some carry imaging systems that can capture "video from long distances, even at night," while others have stingrays or dirtboxes on board to capture cellphone signals.

But detailed information about what the NYPD has on board its spy copter is available and can serve to further enlighten. The New York Police Department is the nation's largest local law enforcement agency, and it generally leads the way in acquisition of modern equipment. Where it goes, the rest of the country tends to follow. So an examination of its aerial surveillance capabilities can be instructive for understanding what other law enforcement agencies around the country may be using.

The NYPD's surveillance activities can also be instructive for another reason. The department has repeatedly been criticized for its over-zealous spy programs—including at least one documented case involving its spy copter. So concerns about abuse of such aircraft are not unfounded.

$10 Million Spy Jewel

The public first learned about the NYPD's Bell 412EP surveillance helicopter in October 2003 when a regional New York newspaper published a small story unveiling the recently purchased $9.8 million "jewel." The specially modified chopper, which the department kept parked at Floyd Bennett Field in Brooklyn, was unmarked—meaning it carried no insignia identifying it as law enforcement aircraft. Acquired through a Justice Department grant, it was customized with a photo- and video-surveillance system capable of capturing clear images of license plates—or the faces of individuals—from 1,000 feet away. It could even, the story noted, "pick up the catcher's signals at Yankee Stadium."

It was described as the "most advanced in use by any police force" at the time, and Police Commissioner Ray Kelly noted that it would be used to fight conventional crime, conduct search-and-rescue missions and "play a key role in anti-terrorism efforts."

The NYPD referred to the helicopter only as "23"—a reference to the number of police officers killed in the 9/11 terrorist attacks—and initially the aircraft had no registration number painted on its tail or side. In later investigating the aircraft, WIRED learned that in 2003 the NYPD had asked the FAA to change the original registration number for the aircraft from N2411X to a special one containing the "23" reference—N23FH (believed to be a reference to "23 Fallen Heroes"). NYPD Deputy Inspector Joseph Gallucci also wrote the FAA at the time asking that the registration be handled in an "undercover" manner and that "any inquiries to the registration number be flagged" and referred to Robert Kikel in the NYPD's Aviation Unit. WIRED obtained documents for the aircraft only after learning the original registration number and filing a FOIA request with the FAA.

The camera could beam live footage to police command centers below or to wireless devices in the hands of police commanders.

Five years after that 2003 story about the helicopter was published, the public learned more about the technology installed on the helicopter from an Associated Press article published about it in 2008. That piece described three flat-screen monitors onboard that were displaying Statue of Liberty sightseers from a mile and a half away. It also described the high-powered camera, mounted in a turret below the chopper's nose, that had infrared night-vision capabilities and satellite navigation to zoom in on any address typed into its computer. The system could beam live footage to police command centers below or to wireless devices in the hands of police commanders in the field. The helicopter had been used, the story noted, to track fleeing suspects and to patrol the skies during a visit by Pope Benedict XVI to New York.

A privacy advocate interviewed for the story raised concerns about how the helicopter might be abused, but John Diazo, crew chief for the aircraft, replied, "Obviously, we're not looking into apartments. We don't invade the privacy of individuals. We only want to observe anything that's going on in public."

The New York Police Department's unmarked spy helicopter (N23FH) flies near the Williamsburg Bridge on Saturday, April 13, 2013. Jonathan Fickies/Landov

But the NYPD's surveillance helicopter had in fact already been involved in at least one privacy controversy at the time Diazo made his remark. On the night of August 27, 2004, an officer aboard the helicopter was monitoring several thousand bicyclists conducting a street protest prior to the Republican National Convention when he directed the copter's camera to a nearby balcony. For nearly four minutes he lingered on a music executive and his girlfriend having sex on the terrace of the executive's Second Avenue penthouse. Jeffrey Rosner, the executive, later said he had no idea the helicopter was watching him, let alone filming him. It was dark outside and Rosner and his girlfriend were shielded by a wall of shrubs. But the camera's thermal imaging system saw right through those obstacles and caught them in their intimate embrace.

"When you watch the tape, it makes you feel kind of ill," Rosner later told the New York Times.

The surveillance only came to light after one of the bicyclists on the ground was arrested and demanded to see footage from the helicopter's camera. A police spokesman told the Times that police sometimes videotaped rooftop activity if they thought someone might be in a position to throw objects at officers below. "In this instance, the officer was instructed afterward to terminate taping once it was determined a threat did not exist," he said.

Other cases of abuse might exist, but the NYPD has fought efforts by the ACLU and others to obtain information about its spy aircraft, so it's hard to know for sure.

Shell Companies and Schematics

One of the most intriguing aspects of the recent FBI spy plane stories is the revelation of the web of shell companies the agency has used to register the fleet, all with three-letter names like FVX Research, KQM Aviation, and PXW Services. Many of the shell companies have addresses in Bristow, Virginia, making it easy to single them out.

The NYPD's helicopter, as previously noted, was also registered to an apparent shell company, this one called Montero Inc. in Brooklyn, New York. FAA records show that Montero took ownership of the aircraft from Bell Helicopter, the manufacturer, in 2003. Stephen Vance, identified as president of Montero, signed the registration papers. But efforts by WIRED in 2008 and later to locate Vance and his company were unsuccessful. The Montero address listed on the FAA documents—1957 86th Street, Suite 249 in Brooklyn, NY—was the address for Mailboxes, Etc., a company that provides post office box services to multiple customers. Oddly, after being registered to Montero for more than a decade, the helicopter's registration recently reverted back on April 10 from Montero to Bell Helicopter in Texas.

In addition to revealing the shell ownership, however, the FAA documents for the NYPD helicopter proved interesting for another reason. They provided a detailed list of all the components and modifications the Bell helicopter underwent to meet the NYPD's surveillance needs.

Spy equipment added to the NYPD helicopter in 2003 includes a WESCAM MX-15 Video Imaging System, also described as a Thermal Imager, and a WESCAM SkyPod B Airborne Microwave Transmission System. The latter includes a GPS receiver that allows the camera to zoom in on specified locations.

Additionally, there is a Comant CI 405 GPS antenna installed on the cockpit roof, a Chelton 931-8 Direction Finding system and a Datong Tracking System "for tracking targeted electronic beacons." The latter presumably is for monitoring GPS trackers that law enforcement agencies place surreptitiously on vehicles. (See the documents below for more details about the components installed on the aircraft.)

The equipment installed in the helicopter was likely state-of-the-art at the time it was placed in the aircraft in 2003, but in the intervening decade it no doubt has been surpassed by more powerful technologies. One thing that apparently wasn't installed in the helicopter at the time was a stingray—a device, sometimes called an IMSI catcher or dirtbox, that simulates a cell phone tower in order to trick mobile phones and other devices into connecting them and revealing their location. Stingrays don't just affect targeted phones; they pick up signals emanating from every mobile device in an area and allow authorities not only to track the devices but, with additional information, to identify who might be carrying them.

The FBI told the AP that its surveillance planes use stingrays but only in limited situations and that their use now require a court order. A Wall Street Journal story published last year revealed that the US Marshals Service also operates surveillance planes equipped with stingrays. It's not known if the NYPD helicopter has used them as well.

While law enforcement is using aircraft to secretly spy on people, there are tools available to spy on spy planes.

The irony around the recent revelations about the FBI and US Marshals Service spy planes is that while these law enforcement agencies have been using the aircraft to secretly monitor people on the ground, people on the ground have been monitoring the spy planes. The AP and others have been able to track the movement of the FBI surveillance planes using FlightAware.com, a web site that displays animated maps showing the routes that aircraft owned by the FBI and others take, based on the aircraft registration numbers, flight plans and other data.

Unfortunately, helicopters aren't as easily tracked. The last flight path available on FlightAware for the NYPD's N23FH spy plane is from September 2011 when the helicopter flew from York, Pennsylvania to Newark, NJ one Saturday morning. A representative for FlightAware told WIRED that the site only tracks flights navigated by instrument; not ones navigated by visual means alone, the manner in which helicopters are generally flown. And helicopter pilots also don't generally file flight plans, since they tend to remain within a single region. They'll file a flight plan, he said, only if they leave the region and fly to another state, for example.

As technologies advance, many of the piloted spy craft that currently populate the air from law enforcement agencies will eventually be replaced with unmanned drones that can do the same kinds of surveillance at a fraction of the cost, while at the same time being harder to track.

It's also unclear what kind of oversight will be put in place to ensure that agencies don't abuse them. A recent report by the National Journal noted that only fourteen states currently require law enforcement to obtain a warrant before using drones for surveillance. The friendly skies are getting much less friendly every day.

NYPD Helicopter N23FH