The position of the B. E.F had now become critical As a result of a most skillfully conducted retreat and German errors, the bulk of the British Forces reached the Dunkirk bridgehead. The peril facing the British nation was now suddenly and universally perceived. On May 26, "Operation Dynamo "--the evacuation from Dunkirk began. The seas remained absolutely calm. The Royal Air Force--bitterly maligned at the time by the Army--fought vehemently to deny the enemy the total air supremacy which would have wrecked the operation