It began as a routine naval training exercise. But it would soon become one of the best-documented—and most baffling—UFO sightings of the 21st century.

Witnesses included highly trained military personnel—among them several deeply experienced radar operators and fighter pilots—who at the time of the sightings were at the controls of arguably the most advanced flight technology ever created. And yet none can explain what they saw.

The date was November 14, 2004, and the location was the Pacific Ocean, about 100 miles southwest of San Diego, California. The USS Nimitz Carrier Strike Group, which included the nuclear-powered carrier and the missile cruiser USS Princeton, were conducting a series of drills prior to deployment in the Persian Gulf.

At about 2 p.m., two F/A-18F Super Hornet fighter jets from the Nimitz received an unusual order from an operations officer aboard the Princeton. Already airborne, the pilots were told to stop their training maneuvers and proceed to new coordinates for a “real-world” task.

More ominously, the officer asked if they were carrying live weapons. They replied that they were not.

READ MORE: Interactive Map: UFO Sightings Taken Seriously by the U.S. Government.

An MH-60R Sea Hawk helicopter above the aircraft carrier USS Nimitz, 2013. Stocktrek Images/Getty Images

A puzzling presence at 80,000 feet

The Princeton’s highly advanced radar had been picking up mysterious objects for several days by then. The Navy called them “anomalous aerial vehicles,” or AAVs—a term the military preferred to unidentified flying objects, or UFOs, which had been tainted by its association with flying saucers, little green men and countless crackpots.

According to Kevin Day, the Princeton’s senior radar operator at the time, his screen showed well over 100 AAVs over the course of the week. “Watching them on the display was like watching snow fall from the sky,” he says in his first-ever on-camera interview, for HISTORY’s “Unidentified: Inside America's UFO Investigation.”

According to Day, the AAVs appeared at an altitude greater than 80,000 feet, far higher than commercial or military jets typically fly. Initially, the Princeton’s radar team didn’t believe what they were seeing, chalking up the anomalies to an equipment malfunction. But after they determined that everything was operating as it should and they began detecting instances in which the AAVs dropped with astounding speed to lower, busier airspace, Day approached the Princeton’s commander about taking action.

“I was chomping at the bit,” he says. “I just really wanted to intercept these things.”

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Churning seas, a wingless wonder

Two fighters were diverted to intercept one of the strange objects. When they first arrived on the scene, the pilots didn’t see any flying objects. But they did observe what the lead pilot, Commander David Fravor, later referred to as a “disturbance” in the ocean. The water was churning, with white waves breaking over what looked like a large object just under the surface.

Then they noticed one of the objects flying about 50 feet above the water. Fravor, the commander of the elite Black Aces squadron who was a Top Gun program graduate with more than 16 years of flying experience, described it as about 40 feet long, shaped like a Tic Tac candy and with no obvious means of propulsion: "It's white. It has no wings. It has no rotors. I go, 'Holy sh*t, what is that?'"

Even odder were its swift and erratic movements, which Fravor described to HISTORY as something he had never seen in his life: “This thing would go from one way to another, similar to if you threw a ping-pong ball against the wall.”

Another Navy pilot who served as Fravor’s wingman in the air that day—and who spoke to HISTORY on condition of anonymity—gave an account very similar to Fravor’s. Now a high-ranking Navy officer, she was a rookie pilot back in 2004. She remembered being terrified, watching as the more experienced pilot tried to intercept the strange craft: “It was so unpredictable—high G, rapid velocity, rapid acceleration. So you’re wondering: How can I possibly fight this?”

As Fravor flew around it, he says the craft ascended and came right at his plane: “All of a sudden it kind of turns and rapidly accelerates—beyond anything I’ve seen—crosses my nose, and…it’s gone.”

As the Tic Tac accelerated into the distance, according to Day, Navy jets began launching off the carrier to try and intercept the other mysterious objects the Princeton’s radar was tracking.

While Fravor wasn’t able to capture the encounter on video, one of the pilots who took off after he landed was able to track it down. He managed to capture video of a Tic Tac, using a highly sensitive infrared camera.

Renewed attention to the Nimitz incident

While the Nimitz incident seems to have been known in naval circles and to some UFO/AAV buffs, it didn’t come to wide public attention until 2017, when The New York Times ran an article about the sighting, and released the video of the Tic Tac shot by the Nimitz pilot that day.

The Times also revealed the existence of a little-known Defense Department initiative called the Advanced Aerospace Threat Identification Program, or AATIP. The “shadowy” enterprise, as the Times referred to it, had a budget of just $22 million, less than 0.004% of the department’s total budget. It was said to be a pet project of then-Senate Majority Leader Harry Reid, who had a longtime interest in UFOs.

Although the government told the Times that AATIP had officially shut down in 2012, its former director, Luis Elizondo, insisted it was still operating. Elizondo had left the program in October 2017, protesting that its work wasn’t being taken seriously enough within the Defense Department.

More eyes on the skies

Elizondo has since joined To the Stars Academy, an organization co-founded by Tom DeLonge, best known as guitarist with the band Blink-182. The group’s mission includes promoting UAP research.

Apparently they’ll have plenty to work with. According to Christopher Mellon, a former high-ranking U.S. intelligence official who is now national security adviser to the organization, and numerous pilots HISTORY has spoken with, the Nimitz incident was not an isolated event. There have been more than a dozen incidents off the East Coast—some as recent as 2015.

The Navy, which seems to have made little effort to investigate the Nimitz episode back in 2004, also appears to be taking the subject more seriously now. In late April 2019, the Navy announced it was drafting new guidelines for reporting any sightings of “unidentified aircraft.” The initiative was intended to de-stigmatize such reports and make it easier for service members to come forward with less fear of ridicule.

According to a Navy spokesman: "There have been a number of reports of unauthorized and/or unidentified aircraft entering various military-controlled ranges and designated airspace in recent years.” The Navy, it was announced, was “investigating each and every report.”

As with all things UFO, AAV and UAP, the Nimitz incident has its doubters. Some have suggested the crafts were advanced reconnaissance drones and that the churning water was caused by a submarine. But whatever the now-famous Tic Tac actually was, it’s hard to dispute that the pilots, the radar operators and the infrared camera had seen something. And chances are, it wasn’t just a big breath mint.

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