The crescent screened vulnerable Armada shipping

The Armada could not expose its transports and storeships in a simple line. Heavy galleons held the tips and centre of a crescent, so English attackers first had to pass through a combat screen. Packing the fleet into a circle would have made firing and manoeuvre harder while leaving only a thin outer layer of warships. The crescent balanced protection with forward movement and appears to have worked reasonably well, since few ships were lost before the later anchorage crisis.