A big problem with the Armada was that most of the Spanish ships were remodelled merchant ships, Made for carrying goods. They were not battle ships. They were also wide and heavy and could not move very quickly under sail. But at first this did not look like a problem, since the plan, was not to actually engage with battle with the English on the sea. It was to transport the soldiers to England.
The Armada was met with 197 English ships. Many of the English ship were small vessels so the total ship weight was about equal. But the English used many very fast and long ships which had superior long range fire power. Another Problem was that the Spanish were accustomed to the Mediterranean style of fighting which required ramming, so the type of opponents they were fighting against were using totally different tactics. But all this did not mean that the Armada would definitely have lost the battle against the English.
The English had another tactic that to there surprise, worked a lot better than they expected it to.
The English sent several ships known as "Fire Ships" in the dark towards the armada. Each Fire ship was loaded with several barrels of oil and bundles of wood and all cannons were set to go off when flames reached them. They were set sail as close to the Spanish ships as possible, the fire would be lighted. The crew would then escape at the last possible moment in rowboats. These fire ships sent numerous amounts of Spanish into panic. They cut their anchors, and set sail in the dark. Ships so close together slammed into each other, the whole Spanish crescent (semicircular) formation was totally destroyed.
Also the English had several advantages over Spain. For example...