Narrative:

Before explaining this incident I want to preface it with the fact that on the previous day (evening) I felt it necessary to remove a F/a from my crew for insubordination. I didn't think this had any effect on my mental facs, but all the following day I was my normal self and I noticed I kept making errors that I don't normally make; i.e., setting bugs wrong, calling for checklists at wrong times, not remembering frequencys immediately after readback and the like. Now here is what happened: the first officer, brand new on the medium large transport, asked if he could read an article in reader's digest about the denver crash. We were in cruise for about an hour, all was quiet, so I felt it a good idea since he is brand new on the medium large transport with very little jet or heavy experience. ATC issued a clearance which I read back, 'descend so as to be at 270 in 6 mi or less,' and included a frequency change. We left FL350 so as to comply with the clearance. I waited a few seconds to be sure the clearance was correct and then changed frequencys. In the descent the first officer said he heard FL280 in the clearance. I said I had read back and set FL270. The new frequency was congested and we couldn't get into the controller. Meanwhile we leveled at FL270. Suddenly I realized we were on the approach control frequency, so we returned to our previous frequency and learned in fact the controller had given us FL280. They told us to remain at FL270 and gave us our appropriate frequency. We called the center (cle, sector 4?) once on the ground and they confirmed I had in fact read back FL270, but the controller didn't catch it.

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Original NASA ASRS Text

Title: ACR FLT CREW READBACK NOT CORRECT. CENTER CTLR DOES NOT CATCH ERROR. ALT DEVIATION.

Narrative: BEFORE EXPLAINING THIS INCIDENT I WANT TO PREFACE IT WITH THE FACT THAT ON THE PREVIOUS DAY (EVENING) I FELT IT NECESSARY TO REMOVE A F/A FROM MY CREW FOR INSUBORDINATION. I DIDN'T THINK THIS HAD ANY EFFECT ON MY MENTAL FACS, BUT ALL THE FOLLOWING DAY I WAS MY NORMAL SELF AND I NOTICED I KEPT MAKING ERRORS THAT I DON'T NORMALLY MAKE; I.E., SETTING BUGS WRONG, CALLING FOR CHKLISTS AT WRONG TIMES, NOT REMEMBERING FREQS IMMEDIATELY AFTER READBACK AND THE LIKE. NOW HERE IS WHAT HAPPENED: THE F/O, BRAND NEW ON THE MLG, ASKED IF HE COULD READ AN ARTICLE IN READER'S DIGEST ABOUT THE DENVER CRASH. WE WERE IN CRUISE FOR ABOUT AN HR, ALL WAS QUIET, SO I FELT IT A GOOD IDEA SINCE HE IS BRAND NEW ON THE MLG WITH VERY LITTLE JET OR HEAVY EXPERIENCE. ATC ISSUED A CLRNC WHICH I READ BACK, 'DSND SO AS TO BE AT 270 IN 6 MI OR LESS,' AND INCLUDED A FREQ CHANGE. WE LEFT FL350 SO AS TO COMPLY WITH THE CLRNC. I WAITED A FEW SECS TO BE SURE THE CLRNC WAS CORRECT AND THEN CHANGED FREQS. IN THE DSCNT THE F/O SAID HE HEARD FL280 IN THE CLRNC. I SAID I HAD READ BACK AND SET FL270. THE NEW FREQ WAS CONGESTED AND WE COULDN'T GET INTO THE CTLR. MEANWHILE WE LEVELED AT FL270. SUDDENLY I REALIZED WE WERE ON THE APCH CTL FREQ, SO WE RETURNED TO OUR PREVIOUS FREQ AND LEARNED IN FACT THE CTLR HAD GIVEN US FL280. THEY TOLD US TO REMAIN AT FL270 AND GAVE US OUR APPROPRIATE FREQ. WE CALLED THE CENTER (CLE, SECTOR 4?) ONCE ON THE GND AND THEY CONFIRMED I HAD IN FACT READ BACK FL270, BUT THE CTLR DIDN'T CATCH IT.

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.