Sailors aboard the amphibious assault ship USS Wasp arriving at Subic Bay in the Philippines ahead of the Balikatan exercises. U.S. Navy photo by Mass Communication Specialist 3rd Class Benjamin F. Davella III

The US Navy amphibious assault ship USS Wasp recently sailed in the South China Sea on its way to the annual Balikatan exercises in the Philippines.

The warship was carrying an unusually large load of F-35s, nearly twice as many as normal, The National Interest first noticed.

The heavier configuration could be a first step toward a "light carrier" concept known as the "Lightning carrier," The War Zone said.

The US Navy amphibious assault ship USS Wasp was recently seen sailing in the South China Sea on its way to the Philippines with an unusually heavy configuration of F-35s.

The Wasp was carrying at least 10 F-35B Lightning II stealth fighters, more than the usual load of six of these hard-hitting fifth-generation jet fighters, The National Interest first reported, adding that the warship may be testing the "light carrier" warfighting concept known as the "Lightning carrier."

Sailors on the Wasp. U.S. Navy photo by Mass Communication Specialist 1st Class Daniel Barker

The amphibious assault ship is participating in the Balikatan exercises, during which "US and Philippine forces will conduct amphibious operations, live-fire training, urban operations, aviation operations, and counterterrorism response," the US Navy said in a statement over the weekend announcing the Wasp's arrival.

The annual exercises prepare troops for crises in the Indo-Pacific region. This year's exercises are focused on maritime security, a growing concern as China strives to achieve dominance over strategic waterways.

Read more: US Marines are practicing seizing small islands as a possible China fight looms in the Pacific

It's the first time the Wasp and its Marine Corps F-35B fighters have participated in the Balikatan exercises.

The ship and its fighters "represent an increase in military capability committed to a free and open Indo-Pacific region," the Navy said, using rhetoric consistent with US military freedom-of-navigation operations and bomber flights in the South China Sea, intended to check China.

The Wasp with a heavy F-35 configuration. US Navy/USS Wasp/Facebook

The F-35B is the Marine Corps' variant of the Joint Strike Fighter. The Air Force and Navy are also fielding versions of the fighter, the F-35A and the F-35C, the latter of which is designed to operate on full-size carriers.

The F-35B, which was declared combat-ready in 2015, can perform short takeoffs and vertical landings and is suited for operating on amphibious assault ships.

Read more: US Navy wants to get rid of an aircraft carrier to buy new weapons needed for a next-level fight with China

In addition to at least 10 F-35s, the configuration on the Wasp reportedly included four MV-22 Osprey tilt-rotor aircraft and two MH-60S Seahawk helicopters. Typically, there would be fewer fighters and more rotor aircraft, The War Zone reported.

Deploying with more F-35s than usual could be a first step toward fielding light carriers, an approach that could theoretically boost not only the size of the carrier force but its firepower.

Marine Corps F-35Bs and MV-22 Ospreys on the flight deck of the Wasp. U.S. Navy photo by Mass Communication Specialist 1st Class Daniel Barker

The concept is not without precedent. During the US-led invasion of Iraq in 2003, amphibious assault ships sailed with up to 20 AV-8B Harriers, becoming "Harrier carriers."

The concept has been rebranded as the "Lightning carrier," a reference to the fifth-generation fighters the warships would carry into battle.

The War Zone said an America-class amphibious assault ship - successors to the Wasp class - could carry 16 to 20 F-35s in a light-carrier configuration.

F-35Bs chocked and chained on the flight deck of the Wasp. U.S. Navy photo by Mass Communication Specialist 3rd Class Benjamin F. Davella III

Last fall, a US F-35B launched from the Wasp-class amphibious assault ship USS Essex and conducted the fifth-generation platform's first combat mission, striking militant targets in the Middle East.

In February, the F-35B achieved another first as it carried out simulated strikes in "beast mode," meaning an external ordnance loadout, in the Pacific.

Read more: US Navy's carrier-based F-35C stealth fighters may not be ready for combat after all

The light-carrier concept could see more F-35s doing maritime operations, delivering a massive increase in firepower. This could prove beneficial if the Navy goes ahead with plans to scrap a Nimitz-class carrier as it bets big on the troubled Ford-class carriers and other future combat platforms.

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