Narrative:

*Callback was made due to report narrative and pertinent information being destroyed by post office. Reporter states they were departing dtw en route ord. Had just entered ZOB airspace and were communicating with center. Received clearance to 17000. Passing 15000 center said you were assigned 15000. First officer indicated heard and read back 17000. Controller said ok, if you read back then just remain at 16000, no conflict.

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Original NASA ASRS Text

Title: ACR CALLED BY CTLR AS CLBING TO ALT THOUGHT ASSIGNED. CTLR SAYS ASSIGNED 2000 FT LOWER.

Narrative: *CALLBACK WAS MADE DUE TO RPT NARRATIVE AND PERTINENT INFO BEING DESTROYED BY POST OFFICE. RPTR STATES THEY WERE DEPARTING DTW ENRTE ORD. HAD JUST ENTERED ZOB AIRSPACE AND WERE COMMUNICATING WITH CTR. RECEIVED CLRNC TO 17000. PASSING 15000 CTR SAID YOU WERE ASSIGNED 15000. FO INDICATED HEARD AND READ BACK 17000. CTLR SAID OK, IF YOU READ BACK THEN JUST REMAIN AT 16000, NO CONFLICT.

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.