HMB-1: This Rusty Barge Was Built By The CIA For A Top Secret Cold War Recovery Mission

At first glance, there’s nothing particularly remarkable about the structure sitting just off to the right of the Alameda Ferry Terminal. But, if you knew its history, you’d realize this rather innocuous-looking structure has quite a story to tell: This is HMB-1, a barge that was originally built by the CIA for a highly secretive underwater recovery operation, and that was later used in an experimental stealth ship program for the U.S. Navy.

If you know something about ship repair, you might take it for a floating dry dock, which in fact, it later became. However, the name painted on the rusty-looking hull reads “HMB-1.” Put that name into Google and you’ll find that it’s the Hughes Mining Barge, a 324-foot submersible barge built for Project AZORIAN, the CIA’s attempt to recover a sunken Soviet submarine. This six-year mission was only partially successful, but it is an incredible story.

The story begins in March 1968, when the Soviet “Golf II-class” ballistic missile submarine K-129 sank about 1,500 miles northwest of Hawaii when a snorkel malfunction caused half the ship to flood and the batteries to explode. Although the Soviets couldn’t locate the lost sub because its last known position was uncertain, the U.S. Navy had a pretty good idea where it was. The SOSUS underwater listening network had heard the battery explosion, and the Soviet search-and-rescue effort revealed that a submarine had probably been lost.

What was left of K-129 sank to the ocean floor at a depth of about 16,500 feet. Retrieving anything from such a depth was a huge technological challenge, but K-129 was an intelligence prize worth going after. It carried three SS-N-4 nuclear-armed ballistic missiles, along with Soviet cryptographic equipment and other potentially valuable intelligence. (It later turned out that two of the three missiles had exploded during the sinking.) The CIA therefore developed an elaborate plan to build a ship capable of recovering the remains of the sub while giving the operation a plausible commercial explanation so the Soviets wouldn’t realize what was really taking place.

Designing and executing this plan, codenamed Project AZORIAN, took six years. The CIA made a deal with eccentric billionaire Howard Hughes, who was then living in a Las Vegas penthouse, to build a ship to haul an enormous mechanical claw and hydraulic system that could be lowered to the depth of the K-129 wreckage, grasp the hull, and bring it to the surface. The 618-foot ship was called the Hughes Glomar Explorer, which was publicly explained as a deep-sea mining vessel intended to mine manganese nodules from the sea floor.

The centerpiece of the recovery system was a gigantic mechanical capture vehicle, nicknamed “Clementine,” designed to descend nearly three miles, grab the submarine, and lift it to the surface. Building and handling something that large and complicated presented another problem: how could it be assembled and transferred to the Glomar Explorer without anyone seeing what was really going on?

That’s where HMB-1 came in.

The Hughes Mining Barge was essentially a giant underwater workshop. At 324 feet long, 106 feet wide, and more than 90 feet tall, it was a submersible barge with a retractable roof. “Clementine” could be assembled inside HMB-1 and kept completely out of sight while the barge was towed into position.

For the transfer, HMB-1 was towed to a location near Catalina Island, off the California coast, with the capture vehicle inside. The barge was then partially submerged onto stabilizing piers installed on the seafloor. The Glomar Explorer could maneuver directly over it, open HMB-1’s retractable roof, and lift “Clementine” into the ship’s enormous central “moon pool.” Remarkably, the operation could be carried out in plain sight from shore, the cover story being that the whole operation was simply routine deep-sea mining work.

The Glomar Explorer finally arrived over the K-129 recovery site on July 4, 1974, and the operation began. The capture vehicle was lowered roughly 16,500 feet to the seafloor, where it successfully grabbed the submarine. Unfortunately, the operation didn’t go entirely according to plan. As K-129 was being lifted, part of the capture mechanism failed and a large section of the submarine broke away and fell back to the bottom. The Glomar Explorer managed to recover the remaining section, which contained, among other things, the bodies of six Soviet submariners. The U.S. Navy gave them a burial at sea, complete with a filmed ceremony that was eventually sent to the Soviet Union.

That was HMB-1’s only role in Project Azorian. Afterward, it was towed back north and mothballed at Todd Shipyard in San Francisco.

In 1982, HMB-1 was towed to Lockheed Martin’s facility near Redwood City, where it began a second, equally unusual career as a floating dry dock. This time, its job was to support the construction and sea trials of Sea Shadow, an experimental stealth ship.

Built by Lockheed, Sea Shadow was essentially a floating technology demonstrator, intended to explore how a ship’s radar signature could be minimized while also testing highly stable hull configurations. Some of the technology and design concepts developed through the project would later find applications in oceanographic vessels (Lockheed director Ben Rich discussed the development of the Sea Shadow in his 1994 memoir Skunk Works.)

Sea trials were conducted at night, after which Sea Shadow was returned to HMB-1 and hidden inside during the day, keeping the experimental ship out of prying eyes. After the trials were completed, Sea Shadow was finally revealed to the public and spent 1993–2006 docked in San Diego.

In 2006, both Sea Shadow and HMB-1 were moved to the Suisun Bay Reserve Fleet. The vessels were put up for auction, but nobody wanted Sea Shadow. Eventually, it was sold for scrap to Bay Ship, which duly dismantled the stealth ship—but kept HMB-1.

My own connection to HMB-1 came in 2010, during the many monthly trips I made to the Reserve Fleet between 2005 and 2013, pulling parts for the USS Hornet. We’d arrive around 7:00 a.m., board a motor barge, and head out to whichever row of ships we needed to visit. Once there, we’d disembark and go hunting for parts, which could be anything from a simple metal plate to a twin 3-inch anti-aircraft gun mount.

One morning, we pulled up alongside HMB-1, the vessel at the far right of the row. I didn’t know anything about it at the time, but since it was where we were getting off, I boarded and headed inside. My first clue that something was unusual came as I looked up and wondered how ocean debris had somehow ended up on the overhead above my head. Did this thing sink?

Once inside, things got even stranger. Hanging over me was what appeared to be a gigantic black shadow. I had absolutely no idea what I was standing underneath.

The big ship immediately to HMB-1’s left is BB-61, USS Iowa, which I crossed over many times since the barge would sometimes drop us off there. I also had the privilege of accompanying Richard Landgraff, one of America’s foremost battleship experts and a naval architect who worked on the Iowa-class refit in the 1980s. I knew Richard through the World Affairs Board, and he invited me along on an inspection tour of Iowa before she was moved to Long Beach, a project he was heading.

I got to see the ship—and then some—on that tour, including plenty of areas most visitors never see. Row G was a particularly interesting collection of ships, and I took tons of pictures of all of them before they were eventually scrapped.

And now, a few close shots of the HMB-1:

The last shot is where I finally realized what I had been standing on, as we walked up the gangway to the adjoining USS Mispillion. Suddenly, all those strange details I had noticed earlier made sense.

And there you have it: a rather unassuming old barge that played a part in one of the CIA’s most secretive Cold War operations, and later served as a dry dock for an experimental stealth ship. Today, HMB-1 is just another working dry dock at Bay Ship, its remarkable history largely invisible to anyone passing by—and, until that morning in 2010, completely unknown to me.