cost of approximately ( in 2011) each; 3,225 were launched. SS General Hans Kammler, who as an engineer had constructed several concentration camps including Auschwitz, had a reputation for brutality and had originated the idea of using concentration camp prisoners as slave laborers for the rocket program. More people died manufacturing the V-2 than were killed by its deployment. The V-2 consumed a third of Germany's fuel alcohol production and major portions of other critical technologies: to distil the fuel alcohol for one V-2 launch required 30 tonnes of potatoes at a time when food was becoming scarce. Due to a lack of explosives, some warheads were simply filled with concrete, using the kinetic energy alone for destruction, and sometimes the warhead contained photographic propaganda of German citizens who had died in Allied bombings. The psychological effect of the V-2 was considerable, as the V-2, traveling faster than the speed of sound, gave no warning before impact (unlike bombing planes or the V-1 Flying Bomb, which made a characteristic buzzing sound). There was no effective defence and no risk of pilot or crew casualties. An example of the impression it made is in the reaction of American pilot and future nuclear strategist and Congressional aide William Liscum Borden, who in November 1944 while returning from a nighttime air mission over Holland saw a V-2 in flight on its way to strike London: "It resembled a meteor, streaming red sparks and whizzing past us as though the aircraft were motionless. I became convinced that it was only a matter of time until rockets would expose the United States to direct, transoceanic attack." With the war all but lost, regardless of the factory output of conventional weapons, the Nazis resorted to V-weapons as a tenuous last hope to influence the war militarily (hence Antwerp as V-2 target), as an extension of their desire to "punish" their foes and most importantly to give hope to their sympathizers with their miracle weapon. The V-2 did not affect the outcome of the war, but it resulted in the development of the Intercontinental ballistic missiles of the Cold War, which were also used for space exploration. Unfulfilled plans A submarine-towed launch platform was tested successfully, making it the prototype for submarine-launched ballistic missiles. The project codename was ("Test stand XII"), sometimes termed the rocket U-boat. If deployed, it would have allowed a U-boat to launch V-2