Narrative:

During very busy radio traffic we were given what we heard was a descent from flight level 300 down to 250. The pilot not flying read back to the controller descend to flight level 2-5-0. The controller read back 2-5-0. However his read back must have been cutoff because apparently he said 2-5-0 knots. We began our descent out of flight level 300 passing through FL290 the controller queried our descent. We told him that we were given a descent to flight level 250. At that time he asked us to stop descent at FL280 and fly to 250 knots. We complied.

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Original NASA ASRS Text

Title: An air carrier flight crew reported receiving a descent clearance to FL250 while on the SNKPT1 Arrival to IND; but the Controller meant to issue a speed of 250.

Narrative: During very busy radio traffic we were given what we heard was a descent from flight level 300 down to 250. The pilot not flying read back to the controller descend to flight level 2-5-0. The controller read back 2-5-0. However his read back must have been cutoff because apparently he said 2-5-0 knots. We began our descent out of flight level 300 passing through FL290 the controller queried our descent. We told him that we were given a descent to flight level 250. At that time he asked us to stop descent at FL280 and fly to 250 knots. We complied.

Data retrieved from NASA's ASRS site 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.