If an F-22 and F-35 were both operating in full stealth attack mode behind enemy lines, striking air defenses, searching for air and ground targets, and preparing the airspace with a corridor for a massive, less-stealthy air campaign, then how do the undetectable fifth-generation fighter jets communicate without generating a potentially detectable electrical signal, giving away their position?  

Perhaps an F-35 jet uses its long range sensors to detect an enemy fighter jet on a fast approach, and needs to send targeting data to a nearby F-22 jet so that it can use its aerial maneuverability to engage and destroy the target? What if an F-22 jet suddenly encounters a group of enemy fighter jets and needs surveillance, long-range fires and targeting support from an F-35 jet at greater ranges?

Can these things be accomplished by the aircraft while preserving stealth mode to ensure they are not seen by enemy air defenses?

The answer may be yes, but that depends on testing progress now underway by Northrop Grumman to develop a secure data link between F-22 jets and F-35 jets designed to “preserve and enable” sustained stealth operations. 

Northrop is now testing a “radio translator” engineered to connect an F-22 datalink called Interflight Datalink with an F-35 datalink called Multi-Function Advanced Datalink called MADL.

“We are working on a demonstrator using a radio as a translator to convert data sent from and F-35 to an F-22 in a stealthy manner. It involves using software-defined radio hardware and software and antennas,” Colin Phan, the director of strategy and tech communications for Northrop Grumman, told the National Interest in an interview. 

Stealth mode is preserved by a Northrop anti-jam integrated software-defined radio device called Freedom 550. Software programmable radio works by sending IP packets of data through waveforms to transmit combat-relevant information. Phan explained that there can be one multi-function box that does as many as twenty-five different functions. Stealth mode is sustained, Phan explained, by using a smaller number of modules to connect the two data links together through a converter. Fewer modules help preserve stealthy communications by virtue of decreasing the emissions of an omnidirectional antenna which is more likely to be detected. The broader the signal and the wider the emission, the larger the potentially detectable electronic signature, something which can of course present a risk of being detected.

In recent years, the Air Force has already succeeded in engineering a two-way connectivity exchange between F-35 jets and F-22 jets through LINK 16, however the existing datalink does not enable stealth mode. The Freedom 550 system, by contrast, does.  

Described as a net-centric gateway prototype, Northrop’s Freedom 550 gateway technology is being developed to support the Air Force’s Advanced Battle Management System, a coordinated series of networked combat nodes intended to form “meshed” or interconnected information exchange in combat. The concept is to no longer restrict communications to strictly linear or stovepiped communications channels but rather enable broader functional connectivity to connect weapons and sensors, share surveillance and targeting data across multiple echelons and combat platforms simultaneously.  

Kris Osborn is 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.