With the economic and political support of the United States, in July 1947, Turkey signed contracts with the Westinghouse Electric International Company and J.G. White Engineering Corporation to construct its first international civilian airport, Istanbul's Yeşilköy Airport. As this article will argue, the building of Yeşilköy (1949–53), through a partnership with two American engineering firms, is essentially an early Cold War narrative of transnational exchange involving the multidirectional flow of technical knowledge, expertise and resources between the United States and Turkey; the circulation of geopolitically significant (and frequently competing) military, civilian and government actors; and the local and global implications of these transmissions. Yet the Yeşilköy construction narrative also illustrates how post-war technology transfer was a highly political process of constant adaptation, modification and negotiation. Fraught with unforeseen friction and thorny challenges, Yeşilköy exemplifies the complicated American Cold War strategy of creating and maintaining alliances through engineering knowledge, personnel and practices, often with unintended consequences. Moreover, as a case study, Yeşilköy opens a new window into the cautious science diplomacy that occurred along the Iron Curtain, while filling a notable historiographic gap with respect to aviation in early Cold War Turkey.