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The USAF's "Upside-Down Air Force"
From fighters to tankers, the Upside-Down Air Force has tested numerous inverted aircraft since the early 1970s.
U.S. Air Force According to RADC's 1973 guide on PAMS, the system provided "the capability to conduct engineering evaluations of airborne antennas designed for use on tactical aircraft equipped with ECM [electronic countermeasures] and associated penetration aids. National Archives Collecting antenna pattern data in this manner has been important for the Air Force because the physical appearance of aircraft, even of the same type, can drastically differ based on specific stores configurations. Peter Ricci/AFRL Image It should be noted that the Upside-Down Air Force is just one part of a vast infrastructure that the Department of Defense has created for electromagnetic testing of various vehicle types, which you can read more about in these past War Zone pieces.
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