|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1801 To 2400|
|Locale Reference||atc facility : bwi|
|Altitude||msl bound lower : 10000|
msl bound upper : 11000
|Controlling Facilities||tracon : iad|
|Operator||common carrier : air carrier|
|Make Model Name||Medium Large Transport, Low Wing, 2 Turbojet Eng|
|Flight Phase||descent other|
|Route In Use||arrival star : star|
|Affiliation||government : faa|
|Function||controller : approach|
|Qualification||controller : radar|
|Experience||controller radar : 6|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Anomaly||altitude deviation : overshoot|
non adherence : published procedure
non adherence : clearance
|Independent Detector||other controllera|
|Resolutory Action||none taken : detected after the fact|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||Operational Deviation|
Air carrier X checked in descending to 150 in vicinity of mumsy intersection on EMI1 arrival to bwi. Aircraft was subsequently issued a clearance to 'cross ruane intersection at and maintain 110 speed your discretion.' pilot was switched to balance approach prior to ruane and was later observed descending to 100. I checked with balance and the controller said the pilot thought assigned altitude was 100. I did not hear the readback because I was having a casual conversation with a visiting center controller at the time.
Original NASA ASRS Text
Title: ACR X UNAUTH DSCNT TO WRONG ALT. PLTDEV. CTLR FAILED TO HEAR READBACK OF DSCNT TO WRONG ASSIGNED ALT. OPDEV.
Narrative: ACR X CHKED IN DSNDING TO 150 IN VICINITY OF MUMSY INTXN ON EMI1 ARR TO BWI. ACFT WAS SUBSEQUENTLY ISSUED A CLRNC TO 'CROSS RUANE INTXN AT AND MAINTAIN 110 SPD YOUR DISCRETION.' PLT WAS SWITCHED TO BAL APCH PRIOR TO RUANE AND WAS LATER OBSERVED DSNDING TO 100. I CHKED WITH BAL AND THE CTLR SAID THE PLT THOUGHT ASSIGNED ALT WAS 100. I DID NOT HEAR THE READBACK BECAUSE I WAS HAVING A CASUAL CONVERSATION WITH A VISITING CENTER CTLR AT THE TIME.
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.