Narrative:

While flying this leg of a 3 day trip, a 500' altitude error occurred, which I feel 2 factors caused me to level off 500' lower than assigned. It was my leg into lga and in the cockpit we had a new hire from air carrier Y doing his 25 hours IOE. The flight was normal; cockpit conversation was very minimal concerning the air carrier Y situation, but there was normal conversation at altitude and level flight on air carrier X vs air carrier Y procedures. Since that is what IOE is for, ie, to expose the new pilot to our way of doing things, my mistake was allowing procedure conversation to continue during descent and working close to the ground. Approach assigned me 3500'. The first officer correctly put 3500' in the altitude alerter and even verbally called '4500 for 3500.' I had only heard and locked into my mind 3000', and when the first officer made the 1000' call I thought to myself then about our altimeters and quickly x-chked them,but still mentally was locked in to level off at 3000'. Approach control casually mentioned our error. We acknowledged and corrected. A second, minor factor in this altitude deviation was being assigned an unnatural VFR altitude (3500') instead of either 3000 or 4000'. Even though I mention about the assignment to a VFR altitude, the real cause was my inattn during descent due to having a third person in the cockpit put there to observe and get crew feedback on day-to-day line operations. I have had IOE pilots before with no problem, but on this particular day he was a definite distraction for me.

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Original NASA ASRS Text

Title: ACR MLG ALT DEVIATION, OVERSHOT DURING DESCENT INTO LGA.

Narrative: WHILE FLYING THIS LEG OF A 3 DAY TRIP, A 500' ALT ERROR OCCURRED, WHICH I FEEL 2 FACTORS CAUSED ME TO LEVEL OFF 500' LOWER THAN ASSIGNED. IT WAS MY LEG INTO LGA AND IN THE COCKPIT WE HAD A NEW HIRE FROM ACR Y DOING HIS 25 HRS IOE. THE FLT WAS NORMAL; COCKPIT CONVERSATION WAS VERY MINIMAL CONCERNING THE ACR Y SITUATION, BUT THERE WAS NORMAL CONVERSATION AT ALT AND LEVEL FLT ON ACR X VS ACR Y PROCS. SINCE THAT IS WHAT IOE IS FOR, IE, TO EXPOSE THE NEW PLT TO OUR WAY OF DOING THINGS, MY MISTAKE WAS ALLOWING PROC CONVERSATION TO CONTINUE DURING DSCNT AND WORKING CLOSE TO THE GND. APCH ASSIGNED ME 3500'. THE F/O CORRECTLY PUT 3500' IN THE ALT ALERTER AND EVEN VERBALLY CALLED '4500 FOR 3500.' I HAD ONLY HEARD AND LOCKED INTO MY MIND 3000', AND WHEN THE F/O MADE THE 1000' CALL I THOUGHT TO MYSELF THEN ABOUT OUR ALTIMETERS AND QUICKLY X-CHKED THEM,BUT STILL MENTALLY WAS LOCKED IN TO LEVEL OFF AT 3000'. APCH CTL CASUALLY MENTIONED OUR ERROR. WE ACKNOWLEDGED AND CORRECTED. A SECOND, MINOR FACTOR IN THIS ALT DEVIATION WAS BEING ASSIGNED AN UNNATURAL VFR ALT (3500') INSTEAD OF EITHER 3000 OR 4000'. EVEN THOUGH I MENTION ABOUT THE ASSIGNMENT TO A VFR ALT, THE REAL CAUSE WAS MY INATTN DURING DSCNT DUE TO HAVING A THIRD PERSON IN THE COCKPIT PUT THERE TO OBSERVE AND GET CREW FEEDBACK ON DAY-TO-DAY LINE OPS. I HAVE HAD IOE PLTS BEFORE WITH NO PROB, BUT ON THIS PARTICULAR DAY HE WAS A DEFINITE DISTR FOR ME.

Data retrieved from NASA's ASRS site as of August 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.