 Early aircraft suffered from leaks in wing fuel tanks that required re @-@ sealing after each flight and 85 aircraft were found to have cracks in outer wing ribs and stringers . There were also problems with aileron control cylinders , electrical connectors , and engine compartment fires . Reconnaissance RF @-@ 4Cs made their debut in Vietnam on 30 October 1965 , flying the hazardous post @-@ strike reconnaissance missions . The USAF Thunderbirds used the F @-@ 4E from the 1969 season until 1974 . 
