In July 2019, approximately 50 nautical miles to the west and southwest of San Clemente Island off California, three U.S. Navy ships encountered several Unmanned Aerial Vehicles (UAVs) in four separate incidents. Originally, the sightings of the mystery drones were reported by documentary filmmaker Dave Beaty on his Twitter account.

A friend of one of the crew members of the USS Kidd said that the UAVs resembled the TicTac shape of a famous UFO encounter by FA-18s of the USS Nimitz in the same area back in November of 2004.

As you might expect, this tie-in to a previously documented UFO sighting sent the press into a speculative frenzy. A story by Adam Kehoe and Mike Cecotti for The Drive stoked the mystery angle even further. The writers used the ships’ log entries and publically sourced ship tracking data to make the case that the “brazen” intrusions of these drones represented a serious breach of security. Other media outlets like Yahoo News, Forbes, Fox News, Daily Mail, and the New York Post all filed stories as well about the “Mysterious Drones” and the supposed panic in the U.S. Navy over the four incidents. Officially, the Navy said it had no idea what they were, but the reported details about how it reacted to these mystery drones suggest that it probably knows a great deal more than it is letting on.

The basic outline of the incidents is simple. Over the course of four evenings, as many as six remotely piloted vehicles approached a training exercise consisting of six U.S. warships in the waters off San Clemente Island. The UAVs flew at various altitudes from sea level to over 1,000 feet. They hovered over the ships and their helicopter flight decks at the stern and kept station off their port and starboard sides. They were not blacked out but had red and white lights visible. Other than approaching the warships they did not endanger the safe operation of any of the ships according to Navy log entries.

The Navy vessels immediately set for Emissions Control or “EMCON.” Under EMCON anything emitting any electromagnetic signals aboard the ship, like radios and radar, is turned off and the ship goes dark. The question then becomes, why did the ships shut off all their emitters? The answer is two-fold.

First, this reduces the emissions signature of the vessels which can otherwise be detected many miles away by their radios and radars’ transmissions. It’s obvious the Navy ships were depriving these mystery drones of any ability to detect and record their frequencies for later analysis by whoever launched them.

Second, going quiet makes the ships’ Electronic Surveillance systems work better. Those drones were directed by remote control signals and the ships would be “hoovering” up those radio signals in order to analyze them in great detail. Our destroyers are covered in Electronic Surveillance reception antennae that are scooping up everything that passes their way on the electromagnetic spectrum of signals.

There are 12 different radio bands that go from Extremely Low Frequency to Extremely High Frequency in spectrum spanning from three Hertz to 3,000 Gigahertz. Within these frequency bands, communications signals are sent to car radios, submarines below the surface, and even satellites in space. By listening to the frequencies these drones were using we would be able to tell a lot about where they might be controlled from and by whom.

The United States has an enormously powerful and capable Signals Intelligence apparatus that goes back to before WWII. We were able to break the codes of both the German and Japanese militaries; something invaluable in winning that war. During the Cold War, we were able to distinguish between individual Soviet submarines because our sound detection gear was so sensitive it could tell if a submarine had a ding in one of its propeller blades or if a drive shaft had a slight warp or “lash” to it when it spun.

Signals Intelligence and Surveillance is a major mission of the U.S. Navy. It can sail its ships off another nation’s coast record and analyze radio and radar transmissions and create a catalog of these signals for future use in a conflict. If you know the frequencies your adversaries are using, you can spoof them to send false communications or jam them entirely.

During the encounters with the mystery drones, the ships employed “SNOOPIE” (Ship’s Nautical Or Otherwise Photographic Interpretation and Exploitation) Teams to video and photograph the drones near the ships. This too is part of the Signals Intelligence gathering mission the Navy was engaged in during these encounters. Analysis of those photos and videos will be granular, with careful attention given to each frame. Drone technology is not very complicated: we’ll be able to deduce quite a lot about the control systems, propulsion, sensors, and communications abilities of these drones from photos and videos. Whoever sent them also knows this, which is why the drones came at night and in low visibility weather conditions. Their controllers were hoping to make visual intelligence gathering a bit harder.

It is also of note that the drones were not shot down by the Navy. There may be three reasons for this.

First, the drones weren’t really endangering the ships. Out at sea, it is not uncommon for the warplanes of various nations to buzz each other’s ships. In my own experience, our helicopters would overfly Soviet naval vessels and hover next to them taking pictures. The Soviets would take pictures of us too. Based on the information released so far, the drones were operating outside the 12-mile outer boundary of our territorial waters: They weren’t committing an act of war.

Second, photographing and videoing the drones and capturing their electronic emissions is an intel-gathering opportunity for us.  Learning the capabilities and vulnerabilities of our adversaries is a part of the job for Navy ships like the USS Kidd. They are certainly warships but they are also intelligence gathering platforms as well.

Finally, shooting these mystery drones down in the open ocean could provide a propaganda coup to an adversary. They could claim the drones were conducting an oceanographic mission, had weather instruments on board, or were doing marine life research, and were shot down by the aggressive and paranoid Americans in international waters. And that isn’t good.

Some have asked how the drones even found the Navy ships. That isn’t a mystery either. The destroyers were operating in training areas we use off the coast. When we are out there conducting exercises we actually give notice to foreign countries, especially if live ordinance will be expended. Foreign countries will then issue navigation advisories to their own vessels to avoid these areas so they don’t blunder into the exercises. If we are launching missiles or torpedoes during the exercises we will give very specific notice to adversaries like China and Russia, including the date and location, and invite them to observe. Everyone gets a bit nervous about ballistic missile tests they aren’t aware of and we want to avoid confusion and miscalculation in these things if we can. Additionally, the Russians and Chinese have satellites that can track the location of those ships in real-time, so it wouldn’t be very hard to find them if they were looking.

Now we come to the who and why aspects of these incidents. Whose drones were they and why did they hover over the ships for several days over two weeks in July 2019? I’m prepared to offer some reasonable speculation on this.

I think the mystery drones were most likely Chinese and directed by satellite communications in space. There were other civilian ships in the area that were queried about operating drones merely as a way of confirming what the Navy would have already known just by the broadcast energy of the drones’ radio frequencies. These drones also appeared to be fast and durable suggesting they may have come from a considerable distance away, perhaps as much as 100 miles. The ships in the immediate area were broadcasting Marine AIS or Automatic Identification System. This system, which can be turned off, broadcasts the ship’s name, course, and speed to other vessels and will populate the surface search radar of Navy ships like the USS Kidd. Then, you just look like another “blip” of indeterminate size and origin on the radar scope. These drones were probably launched by one or more of the Marine Militia Fishing ships of the Chinese Navy.

I judge that just three of these vessels could have carried these drones to the west coast of California. All these ships have cargo holds and would be able to store several drones each. If their AIS transceivers were off they could be easily dismissed as just commercial tuna or shrimp boats 60 to 100 miles away. If these drones were flying low over the waves and took an indirect route away from the trawlers and back to them again it would be hard to know where they came from.

As for why? Well, that may be very simple. While the U.S. represents the cutting-edge Gold Standard in UAV technology, that technology isn’t cheap or easy to manufacture. The U.S. is very selective about who may purchase that technology. By contrast, China will sell its most advanced drones to just about anyone who has the money on a “no questions asked” basis. They are not only a bargain but there are dozens of models to choose from. So if you were China and wanted to sell your drones to another country it would be very good marketing to be able to show color images and video of your drones buzzing U.S. Navy ships at night as a kind of, “Look what we can do!” sales pitch.

The explanation is not as sexy and mysterious as UFO sightings and grave breaches of the Navy’s security, but I think that everything that happened out at sea two years ago is pretty simple to not only explain but also understand. It was just business.

And the Navy, which was able to gather intel on the capabilities of these mystery drones, would not want to inform an adversary about what we know and how we know it.