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By Kris Osborn - Warrior Maven

(Washington D.C.) It is a vast expanse …. an indoor warehouse in Fort Worth, Texas, which almost resembles a small city, filled with row after row of F-35 stealth fighter components and structures at various stages of construction. Stealthy looking, green-colored pieces of fuselage, wires, wings, 25mm guns and partially completed aircraft fill up row after row along a seemingly endless walkway. The building is home to large, airplane size workstations in close proximity to one another and populated by workers, experts, engineers and others involved in F-35 creation. The ones showing a box-like lift fan on top of the fuselage are F-35Bs, the ones with the largest wings are F-35Cs and all of the stealthy airframes have a smoothed over rounded area for the aircraft’s 25mm cannon. (I had an opportunity to visit and report on the Fort Worth F-35 production facility several years ago).

Somehow, the process, which culminates in a green looking finished aircraft being wheeled into a climate controlled hangar to receive its grey coat of paint, continued throughout the COVID pandemic. During 2020, F-35 maker Lockheed Martin managed to build 123 F-35As, just slightly below the anticipated pre-COVID number of 141. The 123rd plane for the year, a Lockheed announcement stated, was built at an assembly facility in Italy and delivered to the Italian Air Force.

“In response to COVID-19 related supplier delays, in May the initial annual delivery goal was revised from 141 to 117-123 aircraft to strategically avoid surging, which would increase production-related costs and create future delays and disruption. In 2020, 74 F-35s were delivered to the United States military, 31 to international partner nations and 18 to Foreign Military Sales customers,” a Lockheed announcement writes.

While of course not all of the F-35s are built in Texas, the facility there offers a window into the complexities likely involved in finding ways to ensure continued production during the COVID pandemic. Workers at facilities can be staggered, tested and instructed to follow strict safety protocols, however such measures of course do not fully eliminate risk. However, the biggest challenges to F-35 construction, developers explain, has been ensuring continued productivity and functionality among smaller vendors operating as F-35 suppliers. Many suppliers have smaller facilities, fewer trained experts and fewer employees with which to flex in time of crisis. They also likely have less open, or more dispersed spaces in which to operate.

“Lockheed Martin took proactive measures to mitigate COVID-19 supplier impacts and position the program for the fastest possible recovery by adjusting employee work schedules, maintaining specialized employee skill sets, and providing accelerated payments to small and vulnerable suppliers. Lockheed Martin provided accelerated payments to more than 400 F-35 suppliers in 45 states and Puerto Rico,” the Lockheed essay says.

Lockheed further reports its production infrastructure is on track to meet requirements in coming years, a significant statement given the growing global demand for F-35.

As part of the growing international expansion, which includes large Japanese, Israeli and South Korean F-35 buys, among others, the Royal Australian Air Force has just announced its F-35s have now reached Initial Operating Capacity.

“Australia currently has a fleet of 33 F-35As, and RAAF crews have surpassed more than 8,780 flight hours to date, with more than 45 pilots and 600 maintainers supporting the fleet,” a Lockheed report said. “More than 1,200 pilots and 10,000 maintainers have been trained on the aircraft. Nine nations have F-35s operating from their home soil.”

Check out this special report - following my visit to Fort Worth where theF-35 is built

(Ft. Worth, Texas) -- Filled with stacks of fuselage panels, engine components and a wide assortment of pipes, electronics and avionics, the spralling F-35 construction facility in Ft. Worth, Texas, resembles a small city filled with engineers, mechanics, electricians and airplanes at various stages of construction.

While some stations include vertically-hanging airplane wings, rudders, pipes and intricate collections of wires running through the fuselage, others contain little more than an assortment of seemingly disconnected small parts. Farther along the mile-long construction strip, heavily trafficked by workers, builders and engineers, there are bays with nearly completed F-35 with a light-green exterior. These “about to be finished” F-35s, roll into a separate environmentally-controlled hanger where they await a final coat of blended gray paint - giving the aircraft its color.

After watching a certain amount of varying airplane structures and configurations, to include pipes, computer parts and larger components such as wings, tails, rudders, engines or a mounted 25mm cannon - an observer can begin to discern the differences between the variants. The F-35C is the largest, built with a larger wingspan and tail for carrier landings; the F-35A includes a visible fuselage/wing-mounted 25mm cannon buried beneath a stealthy, rounded exterior blending the weapon into the body of the plane; the F-35B is, developers say, the most expensive and technically complicated of the group.

Mechanical information provided by F-35B engine maker Rolls Royce states “To achieve STOVL, the lift fan component of the LiftSystem operates perpendicular to the flow of air over the aircraft." The LiftFan can operate in crosswinds up to 288mph, Rolls Royce data explains.

During construction of an F-35B, a visible “LiftFan” is engineered into a forward part of the center fuselage just behind the pilot to enable massive downward vertical thrust. Horsepower is sent to the LiftFan from the main engine through a “spiral belevel gear system,” Rollys Royce information states.

This horsepower, when combined with the LiftFan, generates the downward thrust necessary to enable the “hover” ability and vertical landing. An F-35B has what looks like an square door or opening on top of the fuselage behind the pilot and above the lift fan to maximize downward air flow. Engineers explain that the massive thrust, sufficient to propel the aircraft up to speeds beyond the sound barrier, results from a four fold process. Air ducts on either side of the nose “suck” in air to the engine, the air is then compressed before being ignited with gas -- generating what looks like a controlled explosion of fire coming out of the back. The force generated through this process, enables the speed, maneuverability and acceleration of the aircraft.

F-35 Stealth Engineering

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Stealth, or Low-Observability operations hinge entirely upon a specific set of specialized construction techniques, according to engineers familiar with the process. While many if not most of these techniques are, understandably, not available for public reports for security reasons, there are many public elements of the technology written about for public consumption by engineers and many of the industry developers involved in F-35 construction offer detailed profiles of their contributions to the airplane.

A seamless-looking exterior -- devoid or sharp contours, external structures and protruding “edges” more recognizable to enemy radar -- contains a secret blend of composite materials designed to engineer a radar-absorbent airplane. Weapons can be carried internally so as not to expose shapes vulnerable to enemy radar. One commonly discussed element of stealth coating includes the use of “carbon fibers” to - among other things - reflect electromagnetic energy from the surface of the material.

Carbon materials are long-known to have contributed to stealth configurations. Interestingly, a 2016 essay from the Smithsonian Air and Space Museum cites a 2008 expert assessment in which Northrop Grumman engineers sought to determine if a 1943-built German Horten 229 prototype aircraft contained elements of stealth technology - decades ahead of its time. The Nazi aircraft was beset with technical problems and failed a few test flights. It never saw combat, but some of the adhesives, wood and other materials - coupled with its horizontal “all-wing” like configuration, have inspired many to view the aircraft as an early iteration of what became stealth technology. Carbon-like materials were found in the investigation; the engineers Dobrenz and Spadoni write "during our inspection of the Horten 229 at the Smithsonian museum, it appeared that a material similar to carbon black or charcoal was mixed in with the glue between the thin layers of the leading edge shape.”

Whatever the particular composition of material, the stealthy exterior of the F-35 represents an effort to achieve low-observability, survivabilty and lighter weight to enable speed and maneuverability. The seamless F-35 structure is, by design, a result of a particular engineering technique.

“Every hinge, every bolt, every fastener and every panel is closed back up when we are done with work on the airplane, so every time we take off we are in that stealth, non-detectable configuration,” Billie Flynn, F-35 Pilot, Lockheed Martin, told Warrior Maven in an interview.

Electronic pings generated by enemy radar, need specific structures against which to bounce off - sending a return signal. If a fuselage is configured such that it does not offer those structures and edges against which an electromagnetic ping can collide, shapes and contours defining an aircraft are more difficult to detect. In essence, it blinds or removes the return signal, and radar is unable to produce a “rendering” of the fighter jet. As an electronic signal, radar emissions travel at the speed of light - a known entity. If the speed of light, which is fixed, is known and the amount of travel time is also able to be determined, then algorithms can calculate the exact distance, shape and even speed of an object.

“We hide the radar, antenna and fuel -- they are all protrusions which reduce hope that you would ever reduce vulnerability,” Flynn said.

Flynn explained that the stealth engineering contributing to the F-35 has some origins as far back as the Gulf War-era F-117 NightHawk. “With the F-117, we learned how to embed antennas in the leading edge of the airplane. This concept went right into the F-22,” Flynn added.

Lockheed Martin F-117 Night Hawk

Flynn also explained that every F-35 sensor was “flush-mounted,” or built into the skin of the aircraft, making the plane less detectable to enemy radar.

Reducing the heat emissions, or thermal signature, is also known to be of vital importance to preserving stealth. There are a variety of ways this can be accomplished, such as burying engines inside an airplane to lessen the release of heat. The F-35 is built with small coolant tubes running under the wings into the body of the aircraft, designed to dissipate the heat generated by the airplane’s avionics and electrical systems. This avoids overheating and controls overall airplane temperatures. Controlling temperature also enhances the stealth properties of the aircraft. Fuel traveling through pipes underneath the airplane also brings a cooling effect, engineers say.

“We can take full advantage of our stealth signature to penetrate enemy defenses, whereas a 4th Gen fighter will have to operate outside of those areas. We can go inside there and fill that close-in air support role,” Flynn said. “We can stay outside of small arms fire because of the sensor suite.”

Overall, Lockheed has delivered more than 360 airframes to 16 bases worldwide and plans a production rev up to meet growing international and US military demand, Edward “Stevie” Smith, Lockheed’s Domestic Director of Development for the F-35, told Warrior Maven in an interview.

Smith explained that all eight original partners, and new ones such a Japan, South Korea, Belgium and Israel, are advancing plans to produce and develop the aircraft.

“We are on target now for the A-models to be at or less than 80-million per copy,” Smith said.

-- Kris Osborn is the Managing Editor of Warrior Maven and The Defense Editor of The National Interest --

Kris Osborn is the defense editor for the National Interest*.* Osborn previously served at the Pentagon as a Highly Qualified Expert with the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.