Russians in Syria may be trying to collect data on F-22 capabilities

War is Boring:

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Though gaining operational experience on the Sukhoi Su-30SM and Su-34 is likely an important aspect of the Russian deployment, the Russians might have another objective in deploying their latest jets to the theatre. “It may be a way for them to ‘characterize’ the F-22’s radar emissions on their radar warning receivers (RWR) in a real-world environment,” the senior Air Force intelligence official said.

“Not traditional intelligence collection per se, but could be a way to see how their RWRs receive and display an F-22’s radar emissions.”

Another senior U.S. Air Force aviator offered a more succinct assessment. “They probably aren’t planning on getting into any air-to-air engagements with ISIS,” the pilot said. “$100 says their air players are there to soak up trons from our fifth-gen stuff.”
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I suspect that the F-22's may be able to spoof the data they emit also.  They really have not been used that much against ISIL, but they could provide air cover for the attack jets that are hitting ISIL targets.  I suspect the US will also be collecting data on the Russian aircraft and targets.  

The Russian jets involved in Syria are probably all Soviet era aircraft.