The standard ammo type, slug ammunition is basically little lead bullets you fling at hundreds of miles per hour into your foes.
Sharply-pointed rounds, AP ammunition is very effective at stripping away a targets armor, but only slowly damages its fuselage. Killing an enemy fighter with AP rounds takes forever.
Dum-dum rounds are designed to squash and spread out on impact. This makes them significantly less effective against armor but absolutely lethal against unarmored targets - or those that have had their armor removed by AP rounds...
Explosive ammunition is all-round more effective than any other type, but not as efficient as an AP - dumdum combo.
|Ammo||Armor damage||Fuselage damage|
|Slug||x 1||x 1|
|AP||x 2||x 0.5|
|Dum-dum||x 0.5||x 2|
|Explosive||x 1.5||x 1.5|
You can tell when an enemy fighter has lost its armor when smoke and fire starts to trail from a wing. Although this often fades, once it has appeared, the target is considered "unarmored" by the game's damage-calulation system.