Narrative:

Flight from buf to bwi. Cruise flight at FL270. I was flying, the first officer on radios. First officer received a clearance to cross lizio intersection at FL250. I never heard the transmission. As the aircraft began a turn at lizio, the first officer said we needed to descend. This was my first knowledge of the clearance issued by ATC. I immediately descended to FL250. There appeared to be no loss of any separation or conflicts with other aircraft. This incident occurred because of the first officer's failure to carry out with the company's required procedures. The procedure states that the PNF reads back the clearance to ATC and resets the altitude alerter to the new altitude. The PF is to verbally restate the new altitude and verify the altitude alerter is set correctly. The PNF is to continue querying until he has received a verbal acknowledgement from the PF. I never acknowledged the clearance because I never heard it. The first officer did not complete this very important part of the procedure assuming I heard it. Assumptions: we all know the little ditty about them -- in aviation they can be fatal.

Google
 

Original NASA ASRS Text

Title: A B737-700 PIC COMPLAINS OF THE LACK OF COORD COM FROM HIS FO DURING AN ALTDEV, ALT XING RESTR NOT MET, AT LIZIO INTXN, WV.

Narrative: FLT FROM BUF TO BWI. CRUISE FLT AT FL270. I WAS FLYING, THE FO ON RADIOS. FO RECEIVED A CLRNC TO CROSS LIZIO INTXN AT FL250. I NEVER HEARD THE XMISSION. AS THE ACFT BEGAN A TURN AT LIZIO, THE FO SAID WE NEEDED TO DSND. THIS WAS MY FIRST KNOWLEDGE OF THE CLRNC ISSUED BY ATC. I IMMEDIATELY DSNDED TO FL250. THERE APPEARED TO BE NO LOSS OF ANY SEPARATION OR CONFLICTS WITH OTHER ACFT. THIS INCIDENT OCCURRED BECAUSE OF THE FO'S FAILURE TO CARRY OUT WITH THE COMPANY'S REQUIRED PROCS. THE PROC STATES THAT THE PNF READS BACK THE CLRNC TO ATC AND RESETS THE ALT ALERTER TO THE NEW ALT. THE PF IS TO VERBALLY RESTATE THE NEW ALT AND VERIFY THE ALT ALERTER IS SET CORRECTLY. THE PNF IS TO CONTINUE QUERYING UNTIL HE HAS RECEIVED A VERBAL ACKNOWLEDGEMENT FROM THE PF. I NEVER ACKNOWLEDGED THE CLRNC BECAUSE I NEVER HEARD IT. THE FO DID NOT COMPLETE THIS VERY IMPORTANT PART OF THE PROC ASSUMING I HEARD IT. ASSUMPTIONS: WE ALL KNOW THE LITTLE DITTY ABOUT THEM -- IN AVIATION THEY CAN BE FATAL.

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.