India recently announced that they’re on the market for 110 new fighter jets, and they’re willing to fork over more than $15 billion to get them. Naturally this has prompted a great deal of interest from aircraft manufacturers throughout the world. One such manufacturer, America’s Lockheed Martin, has approached the table with a “brand new” fighter they’ve dubbed the F-21, a platform they claim will help bridge the gap between fourth- and fifth-generation fighter platforms for India while serving as a stepping stone leading to new defense technologies in the future.

It may come as a surprise to many that Lockheed Martin, the same company responsible for producing both of the world’s premier fifth-generation platforms—the F-22 Raptor and F-35 Joint Strike Fighter—would be eagerly pushing a brand new fourth-generation platform. For most Americans, though, the F-21 will probably look awfully familiar—and not just because ATAC already produces an F-21 for U.S. service.

Lockheed Martin’s F-21 appears to be the next iteration of their Block 70 F-16, first unveiled in 2015. At the time, they pitched that platform to India and others as “the most advanced fourth-generation fighter on the planet” thanks to a wide array of updates and upgrades fitted throughout the aircraft, including upgraded avionics, radar, ground avoidance systems, and pilot interface.

Proposed F-21 (left) and U.S. Air Force F-16 (right)

Among the most prominent upgrades the Block 70 F-16 boasted was the addition of APG-83 AESA radar, which has the capability to track up to 20 different targets simultaneously and provides the pilot with a far more developed level of situational awareness than can be found in many more dated fourth-generation platforms. The F-21, which would boast the same systems, would leverage the Block 70’s data fusion capabilities in a way that approximates what we’ve come to expect from fifth-generation fighters like the F-35.

In many older F-16 platforms, pilots must rely on multiple screens dedicated to different systems, and then combine the information provided to them to develop a mental picture of the battlespace they’re occupying. This is especially challenging for newer pilots, as the systems can sometimes provide contradictory information. Lockheed Martin’s F-35 Joint Strike Fighter, on the other hand, fuses all of those (and other) feeds into a single data feed that is relayed to pilots via two large touchscreens and an augmented-reality helmet. Enemy aircraft simply appear in the pilot’s vision with diamonds around them and pertinent data displayed alongside, for instance, and ground targets shown with triangles.

The F-21 would almost certainly not offer the same degree of data fusion and helmet interface (the F-35’s helmets alone cost more than $400,000 each), but it would leverage advances in data fusion technology to make the F-16 better equipped to not only locate and identify enemy aircraft, but to provide the F-21 pilot with the awareness they need to intercept, carrying the right speed and approach angle at the merge to carry an advantage into a dogfight with other fourth-generation jets.

Lockheed Martin

Based on Lockheed’s proposal video, it appears that data fusion would be represented in a HUD (heads-up display) as well as on a large cockpit screen, marking one of several significant departures from the aforementioned Block 70 F-16. The conformal fuel tanks high on the aircraft’s fuselage may make for the most dramatic visual difference between the F-21 and the F-16s Americans have grown accustomed to seeing, though they were also present on the Block 70 F-16.

Lockheed faces some stiff competition in the battle for India’s contract, including Russia’s acrobatic Su-35 and Boeing’s F/A-18 Super Hornet (though it remains unclear whether Boeing is pitching a Block II or Block III variant).