The Defiant class is designated as an escort ship. It is almost entirely covered in ablative armour and carries 4 pulse phaser canons and between 2 and 5 torpedo launchers (I have looked at several schematics and seen them on either side of the aft impulse cowling(2), inside the forward warp cowlings(2), and below the main deflector(1)). The class started as a high warp torpedo ship with some exchange of design with the Sovereign Class Starship design team. It later became an escort and attack ship. It has three small shuttle bays and planetary landing gear similar to the much larger Intrepid Class Starship. The forward modual, containing an airlock, torpedo magazine, torpedo launcher and main navigational deflector, is detachable and fitted with a small impulse system so it can act as a single massive warhead for use in emergencies.