Getting ESM detections without enemy active radiations.

[unmerged(196822)]

Played the Flashpoint Keflavik standalone scenario and my F-22 detected enemy carrier group with it's RWR/ESM without any active radar emissions from the carrier group. I checked the detections list and not a single ship from the carrier group was radiating.

 

[unmerged(255172)]

Yes, large ships, especially older ones, can't help giving off some electromagnetic radiation that you can pick up with a very good RWR.

Helicopters are also notorious for being very hard to shield effectively.