SUMMARY On Friday, March 11, 2011, at about 1321 eastern daylight time (EDT), Delta Air Lines flight 2086 (DAL2086), a Boeing 757-200 operating as a regularly scheduled passenger flight under 14 Code of Federal Regulations Part 121 (14 CFR part 121), departed from runway 27R at Hartsfield - Jackson Atlanta International Airport (ATL), Atlanta, Georgia, en route to La Guardia Airport (LGA), New York, New York. The flight crew did not activate the aircraft’s transponder before takeoff, and did not contact air traffic control for approximately eight minutes after departure. The airplane flew through one controller’s airspace and entered another controller’s airspace without coordination before radar and radio contact was established. During the period that DAL2086’s transponder was deactivated, the airplane’s flight data block did not auto-acquire on the TRACON’s radar displays. Consequently, the airplane was displayed only as an enhanced primary target with no identifying information. Although local procedures require that Atlanta Tower controllers verify that departures have a radar data tag before transfer of communications to A80, the tower controllers did not notice that the data block had not auto-acquired when the aircraft departed, and therefore did not notify Atlanta TRACON that DAL2086 had not tagged up. No radar altitude information was available on DAL2086 until the aircraft’s transponder was activated. Review of primary radar data determined that a loss of lateral separation occurred between DAL2086 and the following aircraft: N36638, a Beechcraft 55, with the closest proximity 1.44 miles, N825MK, a Pilatus PC-12, with the closest proximity 0.81 miles, and Atlantic Southeast Airlines flight 5046, a Canadair Regional Jet CRJ-100, with the closest proximity 2.36 miles. No injuries were reported on any of the flights. These incidents occurred during daytime visual meteorological conditions (VMC). N36638, was operating under the provisions of 14 Code of Federal Regulations Part 91 (14 CFR part 91), from Clayton County - Tara Field (4A7), Hampton, Georgia, to John C Tune Airport (JWN), Nashville, Tennessee. N825MK was operating under the provisions of 14 CFR Part 91, from DeKalb-Peachtree (PDK) airport, Atlanta, Georgia to Sarasota/Bradenton International (SRQ) airport, Sarasota, Florida. ASQ5046 was on a regularly scheduled passenger flight from Augusta Regional (AGS) airport, Augusta, Georgia, to ATL, and was operating under the provisions of 14 CFR Part 121. HISTORY OF FLIGHT At about 1318, the ATL tower LC-3 controller instructed DAL2086 to line up and wait at the displaced threshold of 27R. One minute later the controller instructed DAL2086 “…RNAV to FUTBL 27R cleared for takeoff.” DAL2086 had filed the UGAAA 2 RNAV standard instrument departure (SID) from runway 27R, which required the pilot to, “climb heading 272 degrees to intercept course 247 degrees to FUTBL, then on depicted route to UGAAA, maintain 250 knot indicated airspeed until ZALLE, maintain 10,000 feet and expect clearance to filed altitude ten minutes after departure.” At about 1320, one minute after DAL2086 was airborne, the LC-3 controller instructed the pilot to turn left to FUTBL and contact departure. The pilot read back the instructions correctly; however, he did not contact departure control until about 1328. According to the LC-3 controller, when DAL2086 departed, he did not notice that the flight had failed to auto-acquire because his attention was temporarily drawn to a situation at the approach end of runway 27R. At about 1324:54, the Atlanta TRACON south departure controller (DEP-S) realized he had an unaccounted for flight strip on DAL2086 and asked ATL tower about the status of the flight. The LC3 responded that DAL2086 had departed, but they would check into it. The LC informed the Traffic Management Coordinator (TMC) about the inquiry from the DEP-S controller and he began searching the Traffic Situation Display (TSD) for a target. According to the TMC, he saw a target approximately 40 miles northeast of ATL that appeared to be DAL2086. The tower reported that target location to the DEP-S controller. Review of radar data indicated that DAL2086’s primary target was approximately 11 miles south of ATL. Due to the large number of primary targets in that area, the TMC could not positively identify which target was DAL2086, only which target appeared to be following the departure routing that was assigned to DAL2086. According to the DEP-S controller, after he conducted a futile search of the radar display for DAL2086’s target, he informed his supervisor about the situation. They searched for DAL2086's data block and primary target along the general vicinity of the UGAAA2 RNAV route, but could not identify a potential target. At about 1326:53, DAL2086 contacted ATL tower asking; "...you still want us down here at 10?" The LC responded "DAL2086 you’re supposed to be on departure sir." The LC immediately informed the DEP-S controller that DAL2086 had just contacted him. Twenty seconds later, DAL2086 contacted departure stating “…with you at one zero thousand.” The DEP-S controller responded “…say your position.” DAL2086 reported “… just off the east end of the runway…just 8 miles from ESTWU.” The DEP-S controller then requested that the pilot verify that his transponder was turned on. Six seconds later, the pilot reported the transponder was on and the airplane’s radar data block appeared on the controller’s radar display. Radar data indicated that DAL2086 was approximately 20 miles east of ATL. Due to the airplane’s proximity to the arrival traffic inbound to ATL, the departure controller expedited DAL2086's climb to 14,000 feet, and at about 1329 established radar contact. The DEP-S controller immediately handed the airplane off to Atlanta Center since it was approaching their airspace boundary. The flight continued to New York LaGuardia airport without further incident. For further information, see the Air Traffic Control Group Chairman's Factual Report in the docket for this case.