The shift in power enabled the Italian fleet to successfully escort convoys to Africa that, in turn, enabled the Afrika Korps to strike eastward. Loss of Allies' airfields crippled their efforts to supply Malta by air from North Africa, making Malta again dependent upon convoys running the gauntlet through the Mediterranean. Merchant ship convoys, however, were hazardous. In March, only a fifth of the cargo intended for Malta got through Italian naval action and German bombing in the Gulf of Sirte. Air raids in April did heavy damage to Malta's dockyard.