Below Radar is an aircraft specialization in Battlefield 3. It is a permanent upgrade, meaning that it does not have to be selected at the Customization screen unlike other specializations. It is also a passive upgrade - it is not activated via pressing a button like IR Flares for example, instead it takes effect when flying at a low altitude.
|Laser Painter (AH) Guided Missile (SH) Extinguisher (Jet) ← → ECM Jammer (AH) Laser Painter (SH) Maintenance (Jet)|
Protection from heat-seeking and spotting at low altitude
37000 AH score
Below Radar decreases the thermal signature of aircraft flying at low altitude. It hinders spotting and prevents weapon lock from heat-seeking weapons from other aircraft. It also protects against weapon locks from anti-air ground vehicles. It is activated after flying at a low altitude for about 3 seconds, preventing enemy heat-seeking air-to-air missiles from locking on to the player's aircraft.
Below Radar does not protect against shoulder-launched anti-air weapons (Stinger/Igla), nor was it designed to. The user must decide whether the threat from enemy air vehicles outweighs the threat from ground forces.
Compared to Stealth, it allows helicopters to be more effective at close ground support. Low-flying aircraft are, however, more vulnerable to ground fire, including unguided or wire guided rockets, as well as fire from armored vehicles.
To identify if Below Radar is passively activated, look for the altimeter on the heads-up display (HUD) on the aircraft the player is in. It will be somewhere on the side of the screen, representing altitude from ground level as a 1 to 3 digit number, possibly in meters or feet. For Attack and Scout Helicopters, the specialization is activated at 25 or below, which also turns the aircraft's altimeter red, signifying both a dangerously low altitude, and Below Radar active.