The hover tanks in Steel Storm: Burning Retribution are the most numerous enemies you will face. Currently they come in three separate varieties, the Light Tank, Medium Tank and the Lightning Tank. All of them are highly maneuverable and will be seen practically everywhere.
Light Tank
The Light Tanks are distinguished by their tan color and single turret mounted cannon. These units will often approach to medium range, firing single Light Plasma shots at you while strafing or moving from side to side. When shot at, these units are quick to retreat to a longer range while still firing at you.
These are the weakest of the enemies you face but also the most numerous. Beyond the first few levels you can expect to see these in large groups and ambushes all the time. Minigun fire or a sweep with the beam cannon is your best bet to destroy these units at long range, thanks to those weapons instant hit mechanism, while Rocket Pods are the effective choice when groups of them are at close to medium range.
Medium Tank
Medium Tanks are a more heavily armed and armored version of the Light Tank, firing bursts of Light Plasma bolts at a time while moving with a slower speed than the light variety.
These show up more as you progress into the game and will often be found in larger numbers in more significant areas. These units will attempt to dodge your fire to, after approaching to medium range but a far less adept at doing so.
Lightning Tank
Lightning Tanks are quite possibly the most dangerous of all the small Tanks. These units posses a weapon similar to the Thunderbolt which is extremely short range and does only a slight amount of damage to you, however has the potent secondary effect of disabling your secondary, special and primary energy weapons, leaving you only with your Miniguns or Flak Cannon with which to defend yourself until the effect wears off.
The Lightning Tank is known for charging straight towards you, even in the face of heavy gun fire in order to zap you with its bolt. Groups of these units are very hazardous and can continuously keep your other weapons disabled, forcing you to retreat or be overwhelmed. Try to out-range them and trigger your Shockwave is they get too close, although the Shockwave is about the same range as their zap, making timing tricky.