Keywords: Model XAE IFF.jpg The first radio recognition IFF system in the U S Model XAE 1937 The airborne equipment developed at NRL shown at the top The shipboard equipment is shown below When in the vicinity of friendly ships the aircraft equipment transmitted a series of coded signals Aboard the ship the Yagi antenna gun shaped equipment was pointed at the aircraft to flash http //www nrl navy mil/Systems/images/iff_2 jpg used on http //www nrl navy mil/content php P FRIENDFOE 1937 Naval Research Laboratory edited by User Dammit to remove text PD-USGov-Military-Navy IFF transponders |