program. This was reconsidered due to the cost of that version and instead, under the Peace Rhine program, the Luftwaffe purchased the F-4F, which was based on the F-4E. The F-4F had one of the seven fuselage fuel tanks omitted along with the capability to carry AIM-7 Sparrow missiles and bombs. It was equipped with air combat maneuvering leading edge slats and had a higher thrust to weight ratio, approaching 1:1 when fuel was low. The first example, serial number 3701, first flew on 18 March 1973. The first eight were sent to George AFB where crew training was carried out. In 1976, these trainers were replaced with 10 F-4Es, which stayed in the U.S. One of the "F"s, serial number 72-118, remained at Eglin AFB as an experimental project aircraft. Units equipped with F-4F included Jagdgeschwader 71 "Richthofen", Wittmund, commencing in May 1974, and Jagdgeschwader 74 "Mölders", Neuburg an der Donau, September 1975. In April 1975, deliveries started to JaboG 36, Rheine-Hopsten and finally JaboG 35, Pferdsfeld. Operationally, the F-4Fs used by JG 71 and JG 74 were employed in the air-to-air role, while those used by JaboG 35 and 36 were used in air-to-air and air-to-ground roles. Weapons used on the F-4F included the Mk 82 retarded bomb, BL755 cluster bomb unit and AIM-9 Sidewinders. Later on, an AGM-65 Maverick capability was added, with a pair of missiles housed in a single launcher. Aircrew training Luftwaffe aircrew training was conducted by the USAF at Sheppard AFB. The program included 13 months flying the T-37 and T-38, for a total of 200 hours for pilots and 85 hours for navigators. Training in Europe was limited to a minimum of 500 ft (150 m) altitude, with special ranges permitting flight as low as 200 ft (60 m). Advanced training was conducted in Canada at CFB Goose Bay and at Decimomannu in Sardinia. Losses By 1990, Phantom losses were 21 F-4Fs and 15 RF-4Es. RF-4E upgrades and disposal Reconnaissance Phantom updates were carried out during several separate programs. Under the Peace Trout program, one RF-4E upgrade had an ELINT system installed in the nose, based on the APR-39 of the F-4G. Another RF-4E update was the installation of provision for bombs with up to six BL-755, or 5,000 lb (2,268 kg) of other external stores, and an ALE-40 chaff launcher along with a bombing system and newer cameras. In 1988, the