Why invasion required defeating both British sea and air power

The Battle of Britain appears here as a combined air-and-sea campaign rather than an isolated fighter contest. Germany needed air superiority to cross the Channel and prevent the Royal Navy from breaking up an invasion force. British naval dominance meant air attacks alone could not create a permanent strategic decision while the fleet remained able to intervene. Dispersed grass airfields were difficult to disable for long because they lacked a single paved runway whose destruction could close the whole field. Heavy bombers could reach farther, but their more distant bases added another geographical constraint to the air campaign.