Narrative:

ZID issued clearance to descend to FL240. Captain acknowledged, first officer set altitude alerter to FL240 and captain confirmed with double point. Passing FL245, center transmitted 'confirm level at FL250.' captain responded 'negative, descending to FL240 assigned.' avoidance vectors were issued by center, and, as requested, we climbed to FL250. Subsequently, center transmitted, 'sorry, I thought I gave you FL250, but I see I had no response.' the amended altitude clearance may have been blocked by another radio transmission, however, such an amended clearance was neither received nor acknowledged by our aircraft.

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Original NASA ASRS Text

Title: A B727-200 DSNDING TO FL240 WAS GIVEN RADAR VECTORS AND TOLD TO CLB TO FL250. ARTCC HAD AMENDED THE DSCNT CLRNC TO MAINTAIN FL250 BUT HAD NOT RECEIVED AN ACKNOWLEDGEMENT.

Narrative: ZID ISSUED CLRNC TO DSND TO FL240. CAPT ACKNOWLEDGED, FO SET ALT ALERTER TO FL240 AND CAPT CONFIRMED WITH DOUBLE POINT. PASSING FL245, CTR XMITTED 'CONFIRM LEVEL AT FL250.' CAPT RESPONDED 'NEGATIVE, DSNDING TO FL240 ASSIGNED.' AVOIDANCE VECTORS WERE ISSUED BY CTR, AND, AS REQUESTED, WE CLBED TO FL250. SUBSEQUENTLY, CTR XMITTED, 'SORRY, I THOUGHT I GAVE YOU FL250, BUT I SEE I HAD NO RESPONSE.' THE AMENDED ALT CLRNC MAY HAVE BEEN BLOCKED BY ANOTHER RADIO XMISSION, HOWEVER, SUCH AN AMENDED CLRNC WAS NEITHER RECEIVED NOR ACKNOWLEDGED BY OUR ACFT.

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.