since the beginning of "barbarossa", the offensive against the ussr had not really addressed the crimea as an objective. german planners assumed the area would be captured in mopping-up operations once the bulk of the red army was destroyed west of the dnieper river. but in june, attacks by soviet aircraft from the crimea against romania's oil refineries destroyed 12,000 tons of oil. hitler described the area as an "unsinkable aircraft carrier" and ordered the conquest of ukraine and crimea as vital targets in the directive 33, dated 23 july 1941.