THIS!
The only defence against a laser lock from Soflam, CITV tank station or Laser Painter for the Helicopter/Jet pilot is the ECM jammer which is one of the last unlocks so there are a lot of people that don't have it yet. Even then they often take flares instead which are useless against a laser lock.
I'd also recommend whoring the tanks to unlock the CITV station. A CITV station allows you to jump into a third seat in a tank and then you can lase Tanks, other Vehicles and even aircraft and helicopters. Combine this with a Tank Gunner that has guided shell or some Engineers that are using the javelin(or even better, both!) you can destroy helicopters really easily and lased vehicles suffer more damage from Javelin attacks too as they do a top down attack. A Standard Javelin attack is straight on, even if you 'pop up' before you fire. A single Javelin hit will destroy a helicopter and two will often destroy a tank. The jets are too fast for the guided shell to hit but Javelins can catch a jet if they're not turning too fast. Guided shell against helicopters is awesome. You see them popping Flares and you can't help but smile as the guided shell blows them to pieces!