Soviet aircraft types, the tactical evaluation flights of foreign aircraft were undertaken by Detachment 1, 57th Fighter Weapons Wing. 4477th Test and Evaluation Squadron In July 1975, the 4477th Tactical Evaluation Flight ("Red Eagles") was formed at Nellis AFB as tactical evaluation organization. Also in the early 1970s, the concept of "Aggressor Squadrons", was born, using the Northrop F-5E Tiger II, which was found to be nearly identical in terms of maneuvering and speed with the MiG-21 to train front-line combat pilots in Soviet Air Force tactics. Aggressor training was done where the units went head to head against USAF fighters in mock dogfights at this time to find out and exploit possible weaknesses. Foreign military sales of United States fighter aircraft to Indonesia and Egypt in the mid-1970s to replace the Soviet fighter aircraft allowed these nations to clandestinely transfer un-needed MiG-21 and ultra modern MiG-23s aircraft to the United States for evaluation. Up to 25 of these Soviet aircraft made their way to Groom Lake and pilots assigned to Detachment 1, 57th FWW at Nellis were sent to the facility for training as "Aggressor" pilots. These pilots then were reassigned to the aggressor training units at Clark AB, Philippines, RAF Alconbury, England and Nellis AFB. However, by the mid-1970s, as the fleet of Soviet aircraft grew at Groom Lake, the facilities there were becoming crowded and the MiGs needed another clandestine home. Several locations were considered, Michael Army Airfield at the Dugway Proving Grounds in Utah, and the Gila Bend Air Force Auxiliary Field on the Goldwater Range in Arizona. The Tonopah Test Range Airport, however, was only 70 miles to the northwest of Groom Lake and was on the controlled AEC Test Range, so it better fit the need for a new home. The AEC airport had the potential for improvement and expansion, with the only public land overlooking the base miles away. Although not as hidden as Groom Lake, the airport was remote enough to operate the Soviet aircraft in secrecy. In fact, the security surrounding the Tonopah Test Range was so effective that the new base was not publicly reported as an Air Force military airfield until 1985. On 1 April 1977, the 4477th TEF was reassigned to Tonopah. In December 1977 the 6513th Test Squadron (“Red Hats”) was formed at Edwards AFB to perform technical evaluations of these aircraft. In 1980 the 4477th TEF