Those ships you're attacking are Carriers. Carriers don't show their fighters until combat begins, so what looks like an easy target is actually a deadly force. I can tell that even though your pictures are blank, because I am an extensive user of Carriers, and I also know well what it's like to be on the receiving end of a Carrier attack. This is why, when you see a ship that has relatively low armaments for its size, or if it's classed as a "Support" despite being a Medium/Large/Huge hull, always be wary that these ships are probably Carriers, and plan accordingly.
Carriers are extremely powerful, because they allow a fleet to have more ships than their Logistics would otherwise allow, and those ships are always using one each of the best weapon and armor technology you have available. They effectively make individual Small and Tiny ships obsolete. You'll probably need to start fielding carriers of your own to keep up.
