When I first coined the term "spider tank" back in early 2006 (before that calling it a "squadron tank"), I was convinced we would see them on the battlefield increasingly frequently. Sure enough, spider tanks have become a staple of gang and small fleet warfare. A spider tank is a strategy in which each member of a fleet fits a remote armour repairer or shield transfer in one of their high slots and they repair anyone in the fleet who starts to take damage. When the enemy concentrate their fire on one member of the gang, the gang concentrates their remote repairers on that member to keep him alive.
Read on to find out how a logistics ship can generate capacitor out of thin air and how ECM, long range weaponry and speed can be effectively used as tanks.
A spider tank is typically performed with battleships using large remote armour repairers as a shield option would require the use of valuable mid slots that could be used for important PvP modules. With practice, it becomes possible to use this strategy to resist and repair thousands of damage per second. The main reasons a spider tank may fail are if ships begin to run out of capacitor to repair with or some ships are jammed and unable to repair their gang mates. To reduce the chance of this occurrence, most spider tank battleship setups contain a heavy capacitor booster to keep their capacitor levels up and at least one ECCM module to help resist enemy ECM jammers.
The twinned logistics strategy is an odd but highly effective extension to the spider tank. Logistics ships are specialised tech 2 cruisers that get bonuses to remote modules that aid their gang mates such as remote armour repairers, shield transfers, capacitor transfers and tracking links. These ships get an enormous reduction in the powergrid or CPU need and capacitor usage of those modules as well as a huge bonus to their range. This allows a logistics cruiser to fit several large remote armour repairers or large shield transfers and keep them running for a long time from over 70km away.
While this is impressive enough in itself and will certainly help a fleet stay alive, logistics ships tend to be the primary target in a fleet scenario for this exact reason. The solution to always being the primary target is found in a strange but highly useful quirk of the Amarr and Caldari logistics cruisers, the Guardian and Basilisk respectively. Both of these ships get a large reduction in the capacitor usage of energy transfer arrays, making the arrays send a lot more capacitor than they take to run. If a pair of these cruisers runs one or two large energy transfer arrays on each other, both ships will effectively generate massive amounts of capacitor out of thin air.
This strategy means that a pair of Guardians or Basilisks need not worry about capacitor generation. They can use their mid and low slots for a hard tank and remote repair each other if either of them is attacked. The only thing they really need to be worried about are ECM ships jamming them. Not only will this cut off their access to remote repairing their buddy but it will remove their massive capacitor regeneration, putting the ship at major risk. For this reason, it's vital to use one or two ECCM modules. The Guardian only has two mid slots to begin with and the Basilisk will have to drop two modules from its shield tank to fit two ECCM modules, making this a risky strategy to employ and a difficult one to perfect.