Medieval naval battles have often been described a simply land battles at sea with little maneuvering or tactics. Nothing could be farther from the truth. Fleets used deception, feints, flanking maneuvers and other tactics to gain an advantage.
In many respects the tactics used by the Catalan-Aragonese fleet were similar to those employed by their opponents. The typical tactic when fleets met was to form a line abreast and then to extend the flanks to overreach ends of enemy line in order to attack from the beam. In fleet battles it was not unusual for squadrons in a line abreast to be connected in loose formation by cables running between them (see below left). Often the weaker antagonist would employ this tactic, but not always, such as at the Battle of Malta, when both fleets used this tactic. The cables prevented the enemy fleet from forcing their way between different galleys and isolating them, while still allowing the squadrons to maneuver in a somewhat resisted manner. The use of cabling depended on the circumstances. Often neither side had the time to employ this tactic when the encounter was unexpected. The a flying squadron of lighter galleys would remain in reserve to plug holes in the line, prevent flanking maneuvers, or to try and outflank an opponent. Sagetia were used to carry messages or transfer officials to different warships during a battle. Of course, if both fleets were evenly matched and could not gain an advantage by maneuvering, then it became a slugging match until either squadrons in the opposing fleet broke and fled, or one side gained an advantage and could turn a flank.
When an smaller force met a larger one, the inferior force would lash the galleys closely together to form a floating fortress, such as at the Battle of Las Rosas (see below right). This allowed the defender to quickly move marines and crews from one vessel to another for defense. It, of course left the initiative to the attacker since squadron in this formation would not be able to maneuver. This maneuver seems to have only been used by the Catalans to take advantage of their high forecastles and poops. From the description by the chronicler Muntaner the galleys were brought along side each other and their oars lashed together, but beyond that information is scarce.
The other defensive position was that of a beached fleet. In this case, ships' boats were would be turned on beams end between the beached galleys to act as barricades. The advantage was with the beached fleet as it could quickly move men to where they were needed and the beached vessels were, by definition, impervious to sinking. Roger de Lauria successfully defeated the Genoese-Sicilian at Cape Orlando using this tactic. Likewise a small Catalan squadron drove off an attacking Castilian force at Barcelona in 1359.
Roger de Lauria, however, used other tactics to confuse or lure the enemy into a trap. At the night Battle of Las Formigueras he deliberately hoisted lights similar to the Angevin ones to confuse the enemy. Unlike his contemporaries, he had no quams about engaging in night actions. At the Battle of Naples he used a small squadron to bait the Angevins out and into the waiting main body of the fleet that had been hiding out of sight. Both sides used scouting to ascertain the size, location and disposition of an enemy fleet. Other commanders used these tactics, but there is little doubt Roger of a master of them.
