Narrative:

The problem arose from a faster light transport Y aircraft behind a slower medium large transport X. The faster was descending below the slower aircraft, which was accomplished with sep. Both aircraft put on the next controller, but the second (faster) aircraft was turned over (switched) west/O a handoff. The next controller descended the first (slower) aircraft down. Therefore, the conflict occurred. I don't know if the next controller realized that the faster aircraft was on his frequency and lower than the first. The failure to make a handoff was a mistake on my part. The only way to keep this from happening beside complete controller awareness is a possible computer update to make sure all handoffs automatically handoff by a certain point. This would mean that even aircraft with a carrot over the call sign would automatically handoff. Callback conversation with reporter revealed the following: callback made to reporter to determine the type aircraft involved. Reporter indicated that the incident occurred between ZID and ZAU ARTCC's. Reporter says he thought the light transport had been handed off and gave it a frequency change. ZAU controller apparently didn't see the limited data block and didn't know the light transport was in his airspace. Reporter had an assistant controller who apparently didn't see the incident taking place. Proximity of aircraft placed the incident as a minor infringement.

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Original NASA ASRS Text

Title: MLG DESCENDED TO SAME ALT AS LTT WHO WAS FOLLOWING AND FASTER. ADJACENT ARTCC HAD LESS THAN STANDARD SEPARATION DUE TO NO HANDOFF FROM ZID CTLR.

Narrative: THE PROB AROSE FROM A FASTER LTT Y ACFT BEHIND A SLOWER MLG X. THE FASTER WAS DSNDING BELOW THE SLOWER ACFT, WHICH WAS ACCOMPLISHED WITH SEP. BOTH ACFT PUT ON THE NEXT CTLR, BUT THE SECOND (FASTER) ACFT WAS TURNED OVER (SWITCHED) W/O A HDOF. THE NEXT CTLR DSNDED THE FIRST (SLOWER) ACFT DOWN. THEREFORE, THE CONFLICT OCCURRED. I DON'T KNOW IF THE NEXT CTLR REALIZED THAT THE FASTER ACFT WAS ON HIS FREQ AND LOWER THAN THE FIRST. THE FAILURE TO MAKE A HDOF WAS A MISTAKE ON MY PART. THE ONLY WAY TO KEEP THIS FROM HAPPENING BESIDE COMPLETE CTLR AWARENESS IS A POSSIBLE COMPUTER UPDATE TO MAKE SURE ALL HDOFS AUTOMATICALLY HDOF BY A CERTAIN POINT. THIS WOULD MEAN THAT EVEN ACFT WITH A CARROT OVER THE CALL SIGN WOULD AUTOMATICALLY HDOF. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: CALLBACK MADE TO RPTR TO DETERMINE THE TYPE ACFT INVOLVED. RPTR INDICATED THAT THE INCIDENT OCCURRED BTWN ZID AND ZAU ARTCC'S. RPTR SAYS HE THOUGHT THE LTT HAD BEEN HANDED OFF AND GAVE IT A FREQ CHANGE. ZAU CTLR APPARENTLY DIDN'T SEE THE LIMITED DATA BLOCK AND DIDN'T KNOW THE LTT WAS IN HIS AIRSPACE. RPTR HAD AN ASSISTANT CTLR WHO APPARENTLY DIDN'T SEE THE INCIDENT TAKING PLACE. PROX OF ACFT PLACED THE INCIDENT AS A MINOR INFRINGEMENT.

Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.