Goodyear Wingfoot One prepares to land at Plymouth Airport on Monday June 23, 2025. Goodyear is celebrating 100 years of flight and sent the airship to the area to recognize Goodyear dealer Sullivan Tire celebrating 70 years in business.
A silhouette of the Pathfinder 1 is on screen during LTA Research CEO Brett Crozier's presentation for the Akron Roundtable in Akron, Ohio, on Nov. 20, 2025.

If you've been in the San Francisco Bay Area recently, you might have spotted a giant airship adrift over the Golden Gate Bridge. It may look like a blimp – like the kind used these days for advertising – but it's much bigger.

The huge airship recently spotted in California is the Pathfinder 1, billed as the "largest aircraft in the world" and developed by the company LTA Research. Clocking in at 406.5 feet long and 66 feet wide, the Pathfinder 1 is among a class of airships known as "lighter-than-air" or LTA aircraft. For comparison, a Goodyear blimp is 246 feet long.

LTAs include blimps – such as the famous Goodyear blimp that celebrated its 100th anniversary in 2025 – but also balloons and powered airships.

Pathfinder, which is notably not a blimp, aims to differentiate itself from an era of poor public perception that dates back to the 1937 Hindenburg disaster. Its development and testing around the Bay Area poses an interesting question for the future of airships, said J. Gordon Leishman, a professor in the aeronautical engineering department at Embry-Riddle Aeronautical University.

Airships would have to compete with more established methods for transporting cargo or people to have a viable future in the industry, he said, but they have some advantages that could make them useful.

"There are certain intriguing aspects of lighter-than-air aircraft technology such as airships in terms of what they could contribute to the aviation world," he said.

What to know about 'lighter-than-air' ships

A lighter-than-air aircraft is any aircraft that uses gas that is less dense than air to generate buoyancy, Leishman said. They include balloons (which are unpowered and free-floating), blimps and airships.

So what's the difference between a blimp and other kinds of airship? A blimp is essentially an envelope filled with gas, while other types of airships have some amount of an internal structure; they're called dirigibles or semi-rigid airships. Pathfinder 1 is a rigid airship, not technically a blimp.

There aren't many blimps operating in the world these days, and it's usually easy to tell what a blimp is doing if you happen to spot one – usually advertising for companies like Goodyear or DIRECTV or filming aerial views of sporting events. So when San Franciscans spotted Pathfinder 1 floating near the Golden Gate Bridge, they may have wondered what it was up to.

Goodyear blimps are no longer purely blimps either, said Leishman; they are more like semi-rigid airships, but are widely known as blimps.

What is the airship doing in San Francisco?

LTA Research is conducting flight testing of Pathfinder 1 in the Bay Area to test its "proof-of-concept" aircraft. It first announced in May that it had successfully flown the ship outside the airspace of Moffett Federal Airfield, which once housed blimps and balloons for the U.S. military.

Pathfinder previously underwent tests both tethered and untethered at the airfield in Mountain View, California, outside San Francisco. Last month, the company said it received authorization to fly Pathfinder in an expanded area around San Francisco to test flights of greater distance.

Are blimps and airships making a comeback?

Airships have long suffered a bad reputation as "big, lumbering giants that were unsafe," Leishman said. The Hindenburg disaster, when the airship burst into flames while landing in New Jersey after carrying passengers across the Atlantic, killed 36 people. Early airships including Hindenburg were often filled with hydrogen gas, which is the lightest gas but reactive and potentially explosive. Today, nonreactive helium gas is used instead.

But picture a hospital floating in the sky. Or a smooth, low-flying glide over a national park. That's what LTA Research wants to make a reality, reported the Akron Beacon Journal, part of the USA TODAY Network.

"Why airships? Well, because physics don't lie. Buoyancy is free lift," LTA Research CEO Brett Crozier told a crowd at Akron Roundtable on Nov. 20, the Beacon Journal reported.

"While helicopters burn tremendous fuel just to hover, and while airplanes must maintain forward speed for lift, airships float. (With) modern carbon fiber, fly-by-wire controls and electric propulsion ... suddenly you're not looking backward – you're looking at the future of aviation."

The company behind Pathfinder 1 says on its website that it is working toward a future for lighter-than-air technology to help reach places with no traditional roads, runways or ports. They can be used for transporting disaster relief aid, cargo and people, the company said.

"LTA airships will reshape the air travel and cargo transportation we know today by adapting to a changing world and bringing goods and people to destinations beyond roads, runways, and ports," the site says.

Disaster relief is one unique use for airships, said Leishman. Because airships can travel great distances, require less fuel than other means of travel and don't require a runway, they could potentially reach isolated areas with little infrastructure or areas cut off by natural disasters, he said.

They can also travel just as fast as trucks, which are responsible for transporting most goods in the United States, he said. But it's not clear that there would be a demand for airship transportation: The cost could be too high, despite the overall lower carbon footprint. Lighter-than-air aircrafts are also more susceptible to weather conditions than planes, Leishman said. Plus, there is a helium shortage.

Still, Leishman said interest in lighter-than-air ships has been cyclical, waxing and waning over time.

"Maybe it's a novelty in some ways," he said. "You think, 'maybe flying across the Atlantic in an airship rather than a cruise ship could be a lot of fun.' I don't know, I think I would like to do it."

Contributing: Patrick Williams, Akron Beacon Journal

This article originally appeared on USA TODAY: 'Largest aircraft in the world' seen over US. What is it doing?

Reporting by Jeanine Santucci, USA TODAY / USA TODAY

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