On 6 July 1972, as the result of 7 F-4 Phantoms shot down in a two-week period, a second Disco track was initiated. Flown near the former Alpha orbit over the Gulf of Tonkin, its purpose was to gain better low-altitude coverage in the Hanoi area. At the end of the month Disco was also integrated into "Teaball" control center, a highly classified system established to collate all signal intelligence on North Vietnamese air activity gathered by all sources, including non-military. Disco was used as a conduit through which warnings and control vectors were given, but the delay in Teaball acquiring the information and relaying it through Disco (often using an unreliable radio relay KC-135A Combat Lightning aircraft operating under callsign Luzon) cancelled out its value for use in "real time", and the fact that its existence was kept from US aircrews damaged its credibility. Teaball received direct comms capability but experienced transmission failures with frustrating frequency. Disco remained the primary backup controller but its usefulness remained limited because it directly controlled only MiGCAP missions and could only provide its information to strike, chaff and escort forces via the "Guard" frequency.