Why is there a helicopter flying over my neighborhood every night?

If you live in Chicago, you’ve seen and heard helicopters. Sometimes, it’s obvious what’s going on: a TV news chopper filming rush-hour traffic or a police aircraft hovering near a crime scene. But other helicopters are more mysterious.

Over the years, Curious City has received about a dozen questions from people intrigued — or annoyed — by helicopters buzzing over their neighborhoods, sometimes at odd hours of the night. There was an uptick in these questions last year, when Chicagoans became extra aware of aircraft activity during the federal government’s immigration enforcement crackdown.

Even after Operation Midway Blitz ended last fall, the questions persisted. In late March, Cara Novy asked Curious City about helicopters she has seen and heard flying near her home in the West Town neighborhood on what seems like a nightly schedule for the past couple of years.

“Where are they going?” she said. “What are they doing? What kind of helicopters are they? … They look black. They could be gray. I mean, you can’t see any markings on them.”

Helicopter-curious Chicagoans like Novy can use flight-tracking apps to identify aircraft, but that won’t necessarily explain the reasons why helicopters are flying at a particular place and time. Sometimes, that activity is driven by law enforcement — and not just Midway Blitz. But it also has a lot to do with Federal Aviation Administration flight routes and airspaces.

Like layers of a cake

Novy might be hearing some of those helicopters because she lives near the Kennedy Expressway, which is a main helicopter route. Most of the helicopter routes on the FAA’s map of Chicago-area helicopter routes are above local expressways.

“One of the main corridors is down 290 from the city out to about 294,” said Jim Triggs, chief pilot and director of operations for Midwest Helicopter Airways in suburban Willowbrook. “It’s one of the main corridors a lot of aircraft fly, because you’re right between O’Hare and Midway.”

As Triggs explained, many helicopters you see flying around Chicago are operating within airspace where they don’t need to communicate with air traffic controllers. The airspace that the FAA does monitor is shaped like an upside-down wedding cake, with different tiers depending on where you are.

If you draw a circle several miles around O’Hare Airport and extend it skyward, that’s the center of the wedding cake. There’s a similar one around Midway. Inside those spaces, the FAA controls helicopter traffic from the ground all the way up to 10,000 feet.

As you move farther out from the airports, picture a space opening up near ground level, where you can fly without talking to air traffic controllers. For example, imagine your chopper takes off at O’Hare and heads due east along Foster Avenue. As you cross over the Kennedy, you enter a Class B airspace, where pilots don’t need to talk with air traffic controllers — as long as they don’t fly any higher than 1,900 mean sea level. Chicago is about 600 feet above sea level, so this altitude is roughly 1,300 feet above the ground (not quite as tall as Willis Tower).

Now, continue east. Around where you cross Damen Avenue, you enter yet another zone, where your helicopter can ascend up to 3,000 feet mean sea level (or 2,400 feet above ground) without talking to controllers. Then, when you reach Lake Michigan, the FAA’s map offers a warning: Along the shoreline, there’s “very heavy” helicopter traffic using “visual flight rules” to navigate.

Even when pilots aren’t communicating with the towers at O’Hare and Midway, they are talking with each other via radio, Triggs said. In addition, the aircraft transmit and receive ADS-B data — the same info used in flight-tracking apps. “So, our aircraft will actually give us a map showing where other aircraft are,” said Triggs, whose company lifts heavy objects like air conditioning units and signs onto the tops of buildings.

ADS-B stands for automatic dependent surveillance broadcast; that’s the system aircraft use to send out and receive this flight data. The same data can help people like Novy find out who exactly is flying over their neighborhood.

There’s an app for that

There’s one simple way of identifying helicopters and airplanes as they fly over Chicago: Check out the real-time maps showing aircraft in flight at websites and apps like Flightradar24, FlightAware, AirNav Radar and ADS-B Exchange. Just click on the symbol for an aircraft and you’ll see information about it, along with a line that shows where it’s been flying.

But some of the apps, like Flightradar24, often block the identities of police and government helicopters. That’s why Soren Spicknall, a civic activist who lives on the Far South Side, uses ADS-B Exchange. He said it’s more comprehensive, showing data for helicopters that are masked on other apps.

“The ADS-B Exchange relies really heavily on community-based receivers of the kind of data that aircraft are sending back and forth through the atmosphere, about their position, their altitude, their speed,” Spicknall said.

I tried the ADS-B Exchange for myself. Over a few hours, I looked at a week’s worth of helicopter flights over Chicago.

I counted 53 different helicopters flying over the Chicago area at various times during the last week of April. A news helicopter shared by CBS and Fox spent more time in the air than anyone else, flying for a total of 46 hours, according to the website. No. 2 was a medical helicopter, which spent 30 hours going to and from hospitals. The next busiest helicopters were operated by WGN-TV, the Chicago Fire Department and the Chicago police.

But even ADS-B Exchange doesn’t capture every single flight. Sometimes helicopters vanish from the map.

Midway Blitz aircraft

As a reporter for the independent outlet Unraveled Press, Steve Held kept a close watch on the federal government’s helicopters during Operation Midway Blitz. More recently, he saw a copter flying over his home on the Northwest Side and decided to look it up online.

“I opened up ADS-B Exchange and I was surprised to see actually, there was nothing there. It didn’t show the helicopter over my house at all,” Held said. “They will turn off their transponder when they’re on operations. They actually stop broadcasting this information, so they’re essentially stealth on the app.”

Responding to a question about this, the FAA said aircraft are usually required to transmit ADS-B data. “The only waivers … are for law enforcement, active national security and VIP movement,” a spokesperson said. “The FAA issues very limited exemptions, which it gives at the time of operation.”

Held believes the helicopter he saw over his house was operated by the Department of Homeland Security, which had a lot of aircraft above Chicago during last fall’s Midway Blitz. In one of the most notorious incidents, agents rappelled down from a Black Hawk during a Sept. 30 raid on an apartment building in the South Shore neighborhood. DHS put out a video showing a scene filmed from the helicopter.

The Illinois Accountability Commission condemned this use of a helicopter, writing in a report: “Agents may … have violated agency policy by using dangerous and highly militarized tactics, such as rappelling from a helicopter onto a rooftop in a residential neighborhood, for the purpose of producing social media content and other publicity. According to policing experts, the use of a military helicopter to rappel onto the roof of a residential building for the type of operation executed at South Shore was a significant departure from standard practice because it places residents, bystanders, and the agents in extreme danger from a helicopter mishap.”

Responding to questions about this incident, a DHS spokesperson said, “This operation was performed in full compliance of the law.”

While the South Shore raid became emblematic of the crackdown on immigration, Held said it was more typical for the feds to use helicopters to monitor protesters. “You would see helicopters providing overhead surveillance for what was going on in the crowd, people that they were keeping an eye on,” he said.

Spicknall observed a similar pattern. “If [U.S. Customs and Border Protection] recklessly crashes their vehicle into a corner and then a bunch of community members gather, then sometimes these helicopters are hovering above,” he said.

Andrew Thrasher, a local consultant for immigration law firms, said he saw how the presence of helicopters unsettled some immigrants. “I’ve been in a room with them before and heard a helicopter fly overhead and seen those reactions,” he said. “Just hearing that noise overhead is very concerning for anyone, because of so many unanswered questions. Who is this? Who is flying overhead?”

The feds also used helicopters during car chases. On Oct. 14, in the East Side neighborhood, a DHS helicopter flew overhead as Border Patrol agents raced down the streets in pursuit of a suspected undocumented immigrant. The agency’s own videos captured a supervisor saying, “Hey agents, the bird has eyes. Stop following that vehicle.” In other words, a helicopter was watching, so agents on the ground didn’t need to chase it. But they continued the chase and crashed into the vehicle.

Held, who reported on this incident, said it shows how law enforcement could use helicopters to make chases less dangerous. “I mean, in theory, having the helicopters — yeah, it makes it easier for them to track a vehicle without having to engage in a high-speed chase,” he said.

In response to my questions, DHS defended the actions of its agents, but the department did not address the issue of whether agents should have relied on helicopter surveillance instead of risky driving.

In more recent months, DHS helicopters haven’t been as busy over Chicago. When they do pop up on flight tracking apps, that doesn’t necessarily mean that they’re prepping for a new immigration blitz. “I think those often aren’t immigration enforcement-related,” Held said.

In some cases, people may be seeing a Customs and Border Protection helicopter that’s part of a local task force following stolen cars after carjackings. It’s been part of that task force, which also includes the Chicago police and the Cook County sheriff, since 2021 — long before Midway Blitz.

A CBP spokesperson confirmed that the agency still participates in Chicago’s carjacking task force. The Chicago police did not grant our request for an interview about the department’s use of helicopters.

Traffic from a heliport

Law enforcement activity explains some of the helicopters that our question-asker has noticed around her home in West Town. But not all of it.

Over the course of two nights, Novy jotted down the exact times when she noticed 26 helicopter flights. I used that info to look up helicopters on the ADS-B Exchange’s online map. Most of the flights were taking off from Vertiport Chicago, a heliport that opened in 2015 on the Near West Side. The helicopters flew northeast over Novy’s neighborhood, heading up to the area around Montrose Point, where they circled around. Then they went back.

So it appears Novy regularly hears helicopters flying at odd times of night because she lives under a regular flight path used by the city’s biggest heliport.

Who’s in these helicopters? Vertiport Chicago didn’t answer our inquiry. Triggs, who has used Vertiport, said, “Vertiport Chicago primarily does tours. But it’s part of the Illinois Medical District. A lot of medical helicopters use it.”

Filling a void left by the 2003 closing of downtown’s Meigs Field airport, Vertiport can also serve as a staging point during emergencies, Triggs said. “Should something ever occur, that’s a primary location for military aircraft to come in and out, if need be, to bring humanitarian efforts into the city,” he said.

Triggs said he understands why people get annoyed by helicopter noise, but he stressed that many of these aircraft are doing important work.

“Someone’s just trying to go to bed, might upset them,” he said. “The helicopter could be transporting an infant. A little inconvenience that someone might experience could have just saved a life.”

Robert Loerzel is a freelance journalist, photographer and historian. Follow him on BlueSky at @robertloerzel.bsky.social.