Despite radius and payload constraints, the F-35B is well-suited to meet the Marine Corps’ operational demands.
Out of the three Lockheed Martin F-35 Lightning II variants, the F-35B, in use with the US Marine Corps, is likely the most innovative. Designed specifically for the unique demands of the Marines, the F-35B deviates significantly from the baseline F-35 A-variant, which the Air Force operates from conventional takeoff and landing configurations. Instead, the F-35B offers the Marine Corps flexibility, expeditionary power, and shipboard compatibility, with short takeoff and vertical landing (STOVL) capability, much like the outgoing McDonnell Douglas AV-8B Harrier.
The F-35B Lightning II’s Specifications
- Year Introduced: 2019
- Number Built: ~150+ (as of 2025; production ongoing)
- Length: 51.5 ft (15.7 m)
- Height: 14.7 ft (4.48 m)
- Wingspan: 35 ft (10.7 m)
- Weight:
- Empty weight: ~32,300 lb (14,650 kg)
- Max takeoff weight: ~60,000 lb (27,200 kg)
- Engine: One Pratt & Whitney F135-PW-600 afterburning turbofan with shaft-driven lift fan
- Thrust: 41,000–43,000 lbf with afterburner (rear nozzle swivels for STOVL)
- Top Speed: Mach 1.6 (1,200+ mph, 1,930 km/h)
- Range: ~900 nmi (1,670 km) without refueling
- Service Ceiling: 50,000 ft (15,000 m)
- Loadout:
- Internal bays: Up to 15,000 lb (6,800 kg) of ordnance
- Hardpoints: 6 external pylons (not used during stealth missions)
- Missiles: AIM-120 AMRAAM, AIM-9X Sidewinder, future AIM-260 JATM
- Bombs: JDAM family, Small Diameter Bombs, GBU-12/31/32, nuclear-capable B61 (planned integration)
- Aircrew: 1
It’s Not Easy to Make a Plane Land Vertically!
The defining feature of the F-35B is the aircraft’s STOVL capability, which is necessary as the Marine Corps cannot rely, like the Air Force, on a global network of long runways and hardened bases. Instead, Marines exist to fight amphibious battles, often from ships or austere forward bases, or damaged infrastructure. Accordingly, Marine Corps aircraft often do not have the luxury of gradually taking off under ideal circumstances.
The F-35B relies upon a unique propulsion system, known as the lift fan, to facilitate STOVL operations. First developed by Rolls-Royce, the lift fan system pairs a shaft-driven lift fan behind the cockpit with a swiveling rear exhaust nozzle. The aircraft’s main engine diverts power forward to spin the fan, generating thousands of pounds of vertical lift. Meanwhile, the rear nozzle rotates downwards to balance the aircraft during vertical operations. The result is an F-35 variant that can hover and move much like the Harrier jump jet, only with fifth-generation stealth, data fusion, and interoperability.
The F-35B Needed to Lose Weight for STOVL Capability
Creating an F-35 variant with a lift fan required a fundamental redesign of the baseline A-variant. The B-variant’s lift fan requires significant internal volume, which forced engineers to redesign the fuselage and sacrifice space that, in other variants, would be used to hold fuel. Therefore, the F-35B carries less fuel, which translates into a reduced combat radius—a necessary drawback that Marines are forced to contend with.
Structural compromises were also required to keep the B-variant’s weight within acceptable limits. The B-variant utilizes more composite materials than other variants, along with a smaller internal weapons bay. This means that it cannot carry as large a weapons payload as other variants—often forcing external carriage when missions demand, at the expense of stealth performance.
Still, in spite of these radius and payload constraints, the F-35B is well-suited to meet the Marine Corps’ operational demands. The F-35B enables the service to project air power from Amphibious Ready Groups without relying on the Navy’s carriers or the Air Force’s runways.
Marines also greatly benefit from the F-35’s various fifth-generation capabilities, including sensor fusion, electronic warfare, and networked data sharing. The Marine Corps utilizes its F-35s as a flying command post and intelligence node, enabling them to scout ahead for naval task forces and collect and share intelligence in real-time.
Not surprisingly, the F-35B is the most complex and expensive variant of the F-35 to maintain. The lift fan and swiveling nozzle are intricate pieces of machinery that require meticulous and constant upkeep. In addition, the F-35B cannot match the raw firepower of the A-variant. However, the Marine Corps is not seeking a long-range air superiority fighter, but rather a stealthy command-and-control node that can operate from anywhere—and the F-35B is perfect for these needs.
About the Author: Harrison Kass
Harrison Kass is a senior defense and national security writer at The National Interest. Kass is an attorney and former political candidate who joined the US Air Force as a pilot trainee before being medically discharged. He focuses on military strategy, aerospace, and global security affairs. He holds a JD from the University of Oregon and a master’s in Global Journalism and International Relations from NYU.
Image: Wikimedia Commons.
