The B-17 was primarily employed by the USAAC in the daylight strategic bombing campaign of World War II against German industrial and military targets. The B-17 developed a reputation as an effective bomber, dropping more bombs than any other U.S. aircraft in World War II. Of the 1.5 million tonnes of bombs dropped on Nazi Germany and its occupied territories by U.S. aircraft, 640,000 tonnes were dropped from B-17s. In addition to its role as a bomber, the B-17 was also employed as a transport, antisubmarine aircraft, drone controller, and search-and-rescue aircraft.