Narrative:

On descent to iln we were initially cleared to FL240, then revised to FL280 and given headings (vectors) west of rid. Then cleared to FL260 and told to proceed direct to rid and hold 'left' on the 270 degree radial, 15 mi legs, right turns. We requested an efc but were not given one until he gave a blanket efc of AM00 for all aircraft holding in the area. While holding at FL260 we were cleared to descend to FL240 and read the clearance back. Upon reaching approximately FL244 we were told to climb to FL250. At AM52 we were informed of a possible altitude deviation at AM31. In a telephone conversation with ZID I was told the tapes verified that the controller issued a clearance to us to FL240 and we read that clearance back, when in fact he wanted FL250 since another aircraft was holding at FL240.

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Original NASA ASRS Text

Title: ATC CTLR INADVERTENTLY ASSIGNED ACR FRT ACFT TO HOLD AT THE SAME ALT AS ANOTHER ACR FRT ACFT EXPERIENCING AN EMER.

Narrative: ON DSCNT TO ILN WE WERE INITIALLY CLRED TO FL240, THEN REVISED TO FL280 AND GIVEN HDGS (VECTORS) W OF RID. THEN CLRED TO FL260 AND TOLD TO PROCEED DIRECT TO RID AND HOLD 'L' ON THE 270 DEG RADIAL, 15 MI LEGS, R TURNS. WE REQUESTED AN EFC BUT WERE NOT GIVEN ONE UNTIL HE GAVE A BLANKET EFC OF AM00 FOR ALL ACFT HOLDING IN THE AREA. WHILE HOLDING AT FL260 WE WERE CLRED TO DSND TO FL240 AND READ THE CLRNC BACK. UPON REACHING APPROX FL244 WE WERE TOLD TO CLB TO FL250. AT AM52 WE WERE INFORMED OF A POSSIBLE ALTDEV AT AM31. IN A TELEPHONE CONVERSATION WITH ZID I WAS TOLD THE TAPES VERIFIED THAT THE CTLR ISSUED A CLRNC TO US TO FL240 AND WE READ THAT CLRNC BACK, WHEN IN FACT HE WANTED FL250 SINCE ANOTHER ACFT WAS HOLDING AT FL240.

Data retrieved from NASA's ASRS site as of July 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.