thorough engineer who developed the details necessary for the success of Flettner's helicopters. Dr. Hohenemser's father was also Jewish, yet both remained unharmed during their tenure together throughout the war as they worked to develop the helicopter for military use. While the final product, the Flettner Fl 282 Kolibri ("Hummingbird"), could be factory-assembled, Flettner and Hohenemser insisted that they were the only ones who were capable of assembling the complex intermeshing rotor gearbox assembly. Plans for mass production of 1,000 Flettner Fl 282 helicopters by BMW were disrupted when allied forces bombed the designated factory. At least two other Flettner helicopters were under development when World War II ended. They were the Flettner Fl 285, another reconnaissance helicopter with a two-hour flight limit and capacity to carry two small bombs, and the Flettner Fl 339, a large transport helicopter project designed for approximately 20 passengers. Photo gallery Post World War II Upon the war's conclusion, Anton Flettner was held in the "Dustbin" interrogation camp at Kransberg Castle. After 1945, Flettner, along with many other aviation pioneers, was brought to the United States as part of Operation Paperclip. Flettner and his partner, Kurt Hohenemser, were among the first German emigrants into the United States after World War II. Flettner started Flettner Aircraft Corporation, which developed helicopters for the U.S. military. In 1949, Flettner employed Kurt Hohenemser as a consultant to the Flettner Aircraft Corporation. Flettner and Kurt Hohenemser, who together developed numerous patents in Germany, kept in close contact after both men emigrated to the United States. Flettner's company in the U.S. was not commercially successful, but his work was shared with the US Army Air Forces. Throughout his 14 years in the United States, Flettner was active in carrying out research projects for the US Army, US Air Force, and the US Navy. Flettner became the chief designer of Kaman Aircraft and many of the Flettner design concepts are found in Kaman helicopters of later years. Today the Flettner rotor is in operation as a supplemental propulsion system for transport and research vessels. There are two ships utilizing the concept of the Flettner rotor in a modified form, the turbosail Acyone developed by Jacques-Yves Cousteau in 1985 and the E-Ship 1, a cargo ship that made its first voyage in 2010. Albert Einstein praised the Flettner Rotor ship as having great practical importance. Anton Flettner's colleague and former partner, Kurt