Excerpts from Books and Wikipedia
"On August 6 the armada reached the Straits of Dover and anchored off Calais for the vital rendezvous. But the troops were not ready for boarding. The armada was effectively trapped. The next day Drake sent six fireships into Calais harbor; the result was catastrophic. The Spanish ships cut loose their anchors and lost their defensive formation. Strong winds, sandbanks, and English ships left only a northward retreat. The English fleet now attacked the Spanish ships as they dispersed northward. Only seventy-six ships survived, whereas England lost no ships and only 100 men during the fighting." [Furtado: 1001 Days]