Some solutions to get some connectivity between the data link systems.
As stealth aircraft, F-22s are not equipped with conventional datalinks such as Link-16 which can be easily spotted by enemy SIGINT. Instead, they use a unique stealth-qualified, narrow-beam Intra-Flight Data-Link (IFDL) designed to relay data and synchronize a situational picture only among the Raptors. As this stealth datalink is incompatible with all other communications devices, Raptors cannot communicate with other friendly aircraft.
However, because of a dramatic cutback in the number of Raptors purchased—187 bought for operations, compared to the 648 planned in 1996 to be procured—the aircraft must now communicate with F-35s as well as legacy “fourth-generation” fighters such as the F-15, F-16 and F-18 families.
To address the jets' inabilities to link to one another—or to legacy fighters—in air campaigns, their manufacturer, Lockheed Martin, has demonstrated a new data-linking capability it developed for them secretly through “Project Missouri,'” a proprietary program. During the demonstration, Lockheed validated the use of a Link 16 transmit capability from the twin-engine F-22 Raptor and showcased an exotic waveform developed by L-3 Communications and optimized for low-probability of intercept/low-probability of detection transmissions (LPI/LPD), says Ron Bessire, vice president of technology and innovation at the company's Skunk Works.
The demonstration required 8 hr. of flight time and took place Dec. 17 and 19, 2013, Bessire tells Aviation Week. The trials required use of a U.S. Air Force Raptor and the F-35 Cooperative Avionics Testbed (CATbird), a Boeing 737-based flying laboratory that was used as a Joint Strike Fighter surrogate to test F-35 software. The F-22 also was able to transmit to a Link 16 terminal on the ground.
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