Radar warning receiver
A Radar Warning Receiver (RWR) will inform the pilot about incoming radar radiation. In game there is only a artificial RWR modeled which will show the direction on a clock display. Aircraft in reality most probably had a different form of RWR or even none at all, but for balancing the game they got the War Thunder standart RWR. If a radar is sending a ping at you the RWR will show a radiation symbol on the direction it is coming from. It can show multiple pings at once from different sources. If you see a striped line from those ping towards the center of the RWR it means a radar is tracking you and you should expect a missile being shot at you from this direction. In Update "La Royale" soviet planes got a slightly different RWR with non-precise sectors in the rear which.