Does the solution to a head-on challenge to China’s long-range missile capability not lie in designing a new fighter, but in revamping one that is already on the books? Lockheed Martin thinks so, and its engineers are reaching back to the past and forward to the future to build so-called “Super” F-35s variants that might provide much of the capability of a sixth-generation fighter at a small fraction of the price.
Following its loss of the U.S. Air Force’s Next Generation Air Dominance (NGAD) contract award to Boeing for the F-47, Lockheed Martin is shifting to incorporate the best features of its losing bid into the F-35 Lightning II. “We’re going to port a lot of our own NGAD R&D over to the F-35, and potentially the F-22 as well, striving to get 80 percent of the effectiveness of sixth-generation in stealth, and other aspects at 50 percent of the cost per unit,” said CEO James Taiclet. With more than 3,500 F-35s expected to be in service globally, the potential impact of such an upgrade is enormous.
Central to the redesign process is Darold Cummings, lead designer of the YF-23, whose ideas marry aerodynamic improvements with stealth optimization. He suggests two main approaches: stretching the fuselage to enhance the fineness ratio and fuel storage, and tail substitution with thrust vectoring for pitch, roll, and yaw. “The short length of the F-35, combined with the fuselage cross-sections necessary to contain weapon bays and landing gear, contribute to a poor fineness ratio,” Cummings said. This ratio really the ratio of length to cross-sectional area has a direct impact on the balance of lift to drag at supersonic speeds. The F-16XL resolved this problem with a 56-inch stretch; Cummings’ F-35EX idea would lengthen the fuselage by 60 inches, internal fuel increased by 4,000 pounds of internal fuel plus another 1,500 pounds in a conformal tank shaped like the F-35C’s gun pod, for a total increase of 30 percent over the carrier variant.
Aerodynamically, a longer fuselage decreases wave drag in transonic and supersonic flight, and canards forward of the wing provide additional lifting area and enhance pitch authority. The F-35EX would also share the larger F-35C wing for additional lift, highly beneficial in carrier missions where takeoff runs are short. For the U.S. Navy, this means an extended combat radius essential for remaining out of China’s anti-ship ballistic missiles.
The mid-life F-35FX design goes further, borrowing from the X-44 MANTA’s tailless delta planform and sophisticated 3D thrust-vectoring nozzle. By doing away with vertical and horizontal stabilators, radar cross-section is decreased and supersonic area distribution is enhanced. Internal fuel capacity would increase to approximately 30,000 pounds 50 percent more than the F-35A allowing for deep-strike missions in tanker-free operations. The nozzle itself, based on low-observable axisymmetric concepts flight-tested on modified F-16s, diverts exhaust flow in multiple axes, achieving full control authority with no aerodynamic surfaces and maintaining stealth by reducing radar-reflective edges.
Stealth shaping would be further developed in the eventual long-term F-35GX, where all rear edges are aligned, the forward fuselage is recontoured into a 70-degree chine, and inlets are moved below it. All these modifications are intended to distribute radar energy away from emitters, drawing on experience with both the F-22 and conceptual developments of the X-44.
It is not easy to engineer such modifications onto the F-35’s closely integrated wing-fuselage structure. In contrast to the F-16’s wing mounting to fuselage sides, the F-35’s structural load-bearing structure fuses together wing and body to conserve weight. Cummings works around this by positioning the aft wing spar so that it parallels the fuselage carry-through structure, requiring minimal deep structural redesign. As he explained, “When we did the YF-23, three of the most labor-intensive, painful things were the crew station and canopy, the weapon bay and the landing gear… these things are all done on the F-35.”
In addition to aerodynamics and stealth, Lockheed is also looking at systems enhancements: enhanced passive infrared detectors for emissions-free detection at long range, next-generation electronic warfare sets, and manned-unmanned teaming features built into the airframe to operate “loyal wingman” drones without the need for pods. To power these systems, the F135 Engine Core Upgrade will be needed, increasing thrust and cooling by 50 percent.
The strategic rationale is obvious. A stretched, tailless, thrust-vectoring F-35 version could fly farther from carriers, penetrate deeper into contested airspace, and live longer against next-generation air defenses all while taking advantage of the built-up global logistics and training base. For allies who cannot afford a $300 million F-47, such an aircraft would provide near–sixth-generation performance with no wait, and without the cost.
