Residents of lower Manhattan in New York City got a bit of a scare recently as MH-60 Black Hawk and MH-6 Little Bird helicopters from the U.S. Army’s elite 160th Special Operations Aviation Regiment went zooming between skyscrapers as part of a training exercise. But it's hardly the first time the U.S. military, and the Night Stalkers in particular, have caused a stir with similar so-called "realistic urban training" events, or RUTs. This particular exercise occurred overnight on April 17-18, 2018 and involved at least two MH-60s and two MH-6s, likely carrying additional special operators. According to witnesses, there may have been two additional MH-6 helicopters as well. A subsequent statement from the New York Police Department said that the activities would be confined to areas around the Verrazano and Brooklyn Bridges, as well as near Ellis Island and the Statue of Liberty.

The helicopters flew low enough to pass right by peoples' apartments, rattlingly windows and otherwise causing everything to shake. "Didn’t see them but my whole apartment shook and we hit the floor," one of many concerned citizens posted on Twitter. So far, there is no additional information about what specific "targets" the special operations forces assaulted or the exercise's overall scenario.

There were also reports that a Staten Island Ferry went sailing down the Hudson River flanked by police boats. It is possible that the special operators rappelled onto the vessel in response to a mock terrorist attack or hostage scenario. In addition, the day before the apparent main event, a U.S. Air Force Special Operations Command U-28A spy plane was also spotted on online flight tracking software orbiting in the same general area. This single-engine aircraft, which carries electro-optical and infrared video cameras and signals intelligence systems, was likely conducting a mock intelligence, surveillance, and reconnaissance mission ahead of the simulated raid itself.

Though separate and distinct from rare demonstrations it uses for public relations purposes, the U.S. military still typically describes these sorts of training exercises as a win-win for everyone involved. Special operators get a chance to run through training scenarios in a "live" urban area full of actual potential hazards and bystanders otherwise going about their business and state and municipal authorities sometimes get the opportunity to send National Guard elements, law enforcement personnel, or other first responders to join in and get unique training experience in the process. For instance, in 2014, special operators from Army's 160th Special Operations Aviation Regiment and 7th Special Forces Group and the U.S. Air Force's 22nd Special Tactics Squadron conducted one such exercise, nicknamed Objective Indigo, in South Carolina's capital Columbia. This event also included members of the South Carolina Air and Army National Guard and the Columbia Police Department's SWAT Team. Since they offer unique benefits, even over exercises that occur in special U.S. military urban training facilities, these sorts of events occur with some regularity across the country every year, both at night and during the day. In some cases, they can go essentially unnoticed, as was the case with Objective Indigo, as well as another night-time exercise in 2015 in which elements of Marine Corps Special Operations Command (MARSOC) launched a simulated water-borne raid on a warehouse in Los Angeles, California.

DoD Marine Raiders take part in an urban warfare exercise in Los Angeles, CA.

There is only likely to be increasing demand for these kinds of exercises in the future as the U.S. military, and U.S Special Operations Command in particular, become more concerned about future conflicts in densely populated "megacities." But in large American metropolitan areas, such as New York City, which anecdotally "never sleeps," these realistic exercises often create some level of confusion, or worse. A number of New Yorkers reportedly called 911 in something of a panic during this latest incident, with some saying they were worried the low-flying aircraft might have actually been a terrorist attack akin to 9/11. Residents complained vocally on Twitter that the New York Police Department's official social media alert had gone up after the exercise was already underway and possibly even over entirely. Although New York is clearly an amazing urban training environment, its population is likely uniquely sensitive to the presence of low-flying helicopters. This is not just because of the tight security situation in and around the city, but also because the movement of helicopters around the dense metropolis is strictly regulated. They cannot fly over the city at will and are restricted to landing at a small number of periphery heliports based along Manhattan's shoreline. So just seeing helicopters of any type zipping through Manhattan may be alarming enough to some.

US Army An MH-6 in action.

Back in December of 2016, a daytime training exercise related to a contingency plan to protect then president-elect Donald Trump, similarly gave the Big Apple's denizens a moment of pause. In that case, a single HC-130 Combat King rescue plane and a pair of HH-60G Pave Hawk combat search and rescue helicopters, both from the New York Air National Guard's 106th Rescue Wing, flew various orbits over midtown Manhattan. There are many more examples of similar U.S. military exercises that have gone less than smoothly, at least from a public relations standpoint. In 2008, residents of Portland, Oregon were disconcerted to see special operators in helicopters overhead, with an alert about the training exercise only going out to the general public an hour ahead of time. Media attention subsequently became so intense that the organizers had to move the whole event to another area entirely.

DoD The armed version of the Little Bird, the AH-6, is rolled off a spec-ops MC-130. The small and nimble helicopters can be airborne within minutes of being unloaded.

Here how The War Zone's editor Tyler Rogoway's recalled the incident:

"The arrival of the 160th SOAR MH-6 Little Birds was less of a surprise to a few of us in PDX than most. I watched a C-17 unloaded four Little Birds at Portland Air National Guard base and they were flying in less than an hour after being rolled off the jet's cargo ramp. The helicopters had equipped Navy SEALs hanging off their crew planks and after launching in unison, they flew to downtown Portland at the tail-end of the Friday commute. Once there they zipped down city streets, balanced on their skids 30 stories up on roof ledges while unloading special operators, and kept in continuous motion for hours. People were stunned, and frankly, so was I. It was really was an extreme spectacle to behold. And for a city as 'colorful' as Portland, where black helicopter conspiracies aren't rare, to say the least, many were frightened by what they were seeing. To be honest, that evening mission was about as conspicuous as four helicopters can possibly be. After the sunset, the same four helicopters quickly refueled and launched again, this time flying in very tight formation with just the lead helicopter having its navigational lights on. With the city's ambient lighting you could still see the silhouettes of four Little Birds zipping over Portland at low altitude. This wasn't a localized spectacle either, they covered the entire city that night. They flew above my car at a couple hundred feet in two different locales and I wasn't trying to spot them. It was an incredible sight to behold if you knew what you were looking at. If you didn't it could have been quite confusing. That night and the next day the local news ran lead stories on the Little Birds' big air show along with comments fuming mad citizens. The exercise was moved the next night and then appeared to be canceled, or at least moved to a remote area, for the evenings after that. It seems that a similar sequence of events occurred over Denver months earlier and it too stirred-up a similar reaction."