We got aboard a Coast Guard chopper to see how they bust smugglers and save boaters in the crowded waters around Miami

Air Station Miami opened in 1932 at Dinner Key, south of the city. It moved to Opa-Locka in 1965. Since then it has been involved in major operations throughout the region, including aiding Cubans during the 1980 Mariel boat lift and responding to Hurricane Katrina in 2005 and the 2010 Haitian earthquake.

Air Station Miami's crew now includes 70 officers, 210 enlisted personnel, and civilians and auxiliary personnel operating five MH-65D Dolphin helicopters and five HC-144 Ocean Sentry fixed-wing aircraft.

Pilots Lt. Drake Thornton and Lt. Nathan White and aviation maintenance technician 1st class Colin Hunt are three crew members charged with flying the station's MH-65 helicopters, which have room for two pilots, one flight mechanic, and a rescue diver.

Flying an MH-65 means managing "a ton of moving parts," White said. "Not only do we have the rotor system itself. We've got all of our systems that are essential to each mission," like a hoist to lower and raise divers. "We've got certain things that ... if we launch, go offshore, try to do a mission, and one of those components has failed, then we might as well have not gone."

Keeping it in the air is a balancing act. "You've got a rotor head that's spinning 355 rpm in one direction, and that creates a counter-torque that the tail rotor is counteracting," White said. "You're doing your cyclic, which controls which direction your main rotor is spinning; your pedals, which is the strength that your tail rotor is outputting, and then the power, which is the pitch of the rotor blade."

"Every time you move one" of those things, White added, "the other one's affected as well. So that's why we got two years of flight training before we even get to touch this aircraft, to learn about all those forces."

The MH-65 short-range recovery helicopter was introduced in the early 1980s and has been upgraded in the decades since. It can operate from land and aboard a cutter, with three hours of endurance, a range of about 333 miles, and a cruising speed of about 170 mph.

The entire fleet has since 2007 been outfitted with new engines that added 40% more power and more airborne-use-of-force capabilities.

The Coast Guard has begun upgrading its current MH-65D models to MH-65E. Those enhancements, which include advanced digital avionics in the cockpits to improve pilots' situational awareness, are expected to keep the helicopters in service through 2027.

"These aircraft are over 30 years old. They're old. Our maintainers, they do a great job," White said. "Our automated-flight-control system is probably the thing we have the most issues with ... it basically helps the helicopter stay stable, and we can do it manually, but it's a higher workload and there's more chance for error."

In addition to electro-optical and infrared sensors, the MH-65 can be equipped with a 7.62 mm machine gun and a .50-caliber rifle, both of which are used as part of the Coast Guard's airborne-use-of-force operations, wherein crews can disable the engines on suspect vessels and support Coast Guard boarding teams.

Read more: These photos show why the US Coast Guard's snipers are some of the best in the business

Crews tasked with missions like drug interdiction face threats out in the open ocean. In the crowded airspace over South Florida, the challenges are different. Around Air Station Miami, there are limits on what they can do.

Read more: Coast Guard crews are capturing record amounts of cocaine — here's how they chase down high-seas smugglers

"The first 10 miles of the flight ... we can’t do pre-mission checks, really," White said after a patrol flight on November 15. "We're on the lookout for Cessnas and other civil aircraft that are on the beach line or coming in and out of the litany of airports that are here."

That can cause delays or make Coast Guard crews more busy, White said. There are other precautions they take to operate in that crowd, like keeping anti-collision lights on at all times.

Miami gained notoriety for the drugs and drug-related violence that flooded the city in 1980s and 1990s. During those years, traffickers sneaked in on fast boats or flew in on small aircraft. But law-enforcement pressure pushed smuggling routes elsewhere. Less trafficking activity and more sophisticated smuggling operations have made drug busts less common.

Despite traffickers' shift to other routes, smuggling still takes place in the Caribbean.

Most boaters are day-trippers sailing out of Miami and Ft. Lauderdale. Small, center-console boats a few miles off shore are commonplace, White said. "Now you go 20 miles off and there's someone out there ... they're taking a risk that there might be a search-and-rescue component to them later, like if bad weather rolls in, or they're up to some sort of weird illegal activity."

"We don't get that as much anymore because the drug operations are so sophisticated. They don't give us easy prey like that anymore," White said. High-value human smuggling, typically involving people coming from more distant locations, like Asia, has become more common.

The Coast Guard's HC-144 aircraft have the sensors and the ability to linger unnoticed that are needed to track suspicious vessels and vector in helicopter or boat crews. Up close, 100 or so feet from such a vessel, determining what they're up to can be subjective. "It's like, 'this seems right or this seems wrong,'" White said. The ability to make that distinction is "just built up with experience."

Timing plays a big role in what the Coast Guard can see and stop. It's about a 45-mile run from the Bimini Islands at the western edge of the Bahamas — a distance a high-powered boat can cover in less than an hour.

Time, speed, and distance are major factors in Coast Guard operations wherever they take place.

Catching those boats leaving port — especially at dusk or night, which could indicate nefarious activity — is one thing. "If you find them halfway, through, then all of a sudden you've got 20 minutes to follow this guy, to get a vessel underway, to basically get someone on the ground to where they're going, and you don't always know where they're going," White said. "They change tactics all the time."

Search-and-rescue operations are much more common and can be particularly challenging, especially when a crew member has to be lowered to the water or onto a vessel.

"In general ... hovering and hoisting over the water at night is by far the most dangerous thing we do," White said. "We're down 30 feet above the water, where one second will put you and your crew in."

"Fortunately we get a lot of training doing it," White added, saying they practice it almost weekly and sometimes train other service branches. "It is one thing that the Coast Guard's very specialized at, because hovering over the water is a challenging thing, especially at night, because you just don't have visual reference to the outside."

The Coast Guard isn't the only one out there. Bilateral agreements connect the service with almost all of its counterparts in the Caribbean, allowing Coast Guard crews to operate in their jurisdictions. Chief of among them is the Royal Bahamian Defense Force, which is both geographically close and has the capabilities to aid operations like search and rescue.

A number of US agencies also contribute to the "team effort," White said. Immigration and Customs Enforcement, the Homeland Security Department, and others are "feeding information to us, because we have the aircraft. They don't have the same capabilities that we do in terms of our aircraft, but they are very intel-driven."

"We're sort of the pointy end of the spear, and they're back providing us info," White said of those partners. "Then once we get [suspects], we handcuff them ... whatever needs to be done, and you have [the Department of Justice] who's prosecuting the case."