Why was Washington at a disadvantage at Long Island?

Because the British where stronger and had more supplies then Washington abs his crew

General George Washington knew he had badly miscalculated. On August 27, 1776, British forces under a far more experienced military professional, General Sir William Howe, had soundly drubbed the American army in the Battle of Long Island and were now poised to finish it off. Outnumbered and out - generaled, with their backs to the East River and the British in front of them, the Americans appeared doomed. If Washington lost his army, it could mean the end of the Revolution.

dude lost