Narrative:

During level off at FL310, first officer attention diverted by captain's observation and remark about a topographical landmark near pgs VOR. The distraction, though momentary, allowed the aircraft to overshoot FL310. Recognition and quick recovery kept altitude deviation minimal, however ZLA observed the overshoot and restated the altitude clearance of FL310. ATC further requested a callback when level FL310 because of traffic in the vicinity. Subsequently, the flight continued west/O further incident. Contributing points for consideration: this airline company operates medium large transport a and medium large transport B. The medium large transport B has a more sophisticated autoplt system with altitude capture/hold, as well as dual electric altimeters that always read the same. The medium large transport a does not, and requires much more concentration, with a cross scan to the captain's electric altimeter with respect to the transponder and encoding. The first officer's barometric altimeter usually reads 100-200 different (usually higher) at altitude. In this aircraft the first officer's altimeter read approximately 150' lower (than the captain's). The captain's remarks about a landmark drew the attention of the first officer at a critical time--while in level off to cruise altitude. This distraction broke the first officer's scan of both altimeters to outside the aircraft, allowing the aircraft to deviate above FL310. The previous leg flown by the first officer was in an medium large transport B. Although instrumentation in both aircraft is similar, the medium large transport a does not have the medium large transport B autoplt system that includes altitude capture hold. This requires concentrated effort by all pilots to distinguish the difference on days of multiple legs with aircraft changes, especially for new first officer's. With regard to ATC, the first officer had recognized the overshoot at 31300' on his barometric altimeter and was recovering when ATC repeated the clearance to FL310. When ATC next requested the flight's altitude, the captain responded with 31500' (his altimeter) that the flight was recovering from an overshoot. Another ATC voice requested the flight call level at FL310, to which the captain immediately responded 'level FL310,' as the aircraft had quickly recovered. ATC then stated the flight had traffic at FL330 and 7 mi. The captain acknowledged and repeated 'level at FL310.' note: this communication between ATC and the captain was continuous and uninterrupted, and the entire incident spanned approximately 10-15 seconds. Again, the aircraft was level FL310, acknowledged as such prior to ATC's advisory of the traffic at 7 mi and FL330, and does not appear any infringement of airspace took place with that traffic. The flight continued west/O further incident or conversation from ATC with regard to what had taken place. Resolution: for this pilot, this incident was a rare occurrence, a blow to personal standards and performance, yet a humbling, learning experience. As a new first officer with this airline, a continuing learning effort and diligence with respect to the differing aircraft will enhance my personal strive for absolute discipline and professionalism in flying I think the chain of events speak for the contributing causes for this incident, and again, personal effort will prevent a recurrence. Supplemental information from acn 94466: at FL300 I called out '1000 to go.' altitude alert sounded. Directed my attention outside the aircraft. Next call was by ZLA with, 'you were only cleared to FL310...say your altitude.' a glance at my altimeter showed our altitude at FL315. I immediately motioned the first officer to level off and at that time the altitude alert went off and the first officer rapidly started to correct back to FL310. The first officers comment was interesting. He said, 'I guess I thought I was in an medium large transport B and it was going to level at FL310 for me.

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Original NASA ASRS Text

Title: ACR MLG SIGHTSEEING OVERSHOOTS ALT ON CLIMB.

Narrative: DURING LEVEL OFF AT FL310, F/O ATTN DIVERTED BY CAPT'S OBSERVATION AND REMARK ABOUT A TOPOGRAPHICAL LANDMARK NEAR PGS VOR. THE DISTR, THOUGH MOMENTARY, ALLOWED THE ACFT TO OVERSHOOT FL310. RECOGNITION AND QUICK RECOVERY KEPT ALT DEVIATION MINIMAL, HOWEVER ZLA OBSERVED THE OVERSHOOT AND RESTATED THE ALT CLRNC OF FL310. ATC FURTHER REQUESTED A CALLBACK WHEN LEVEL FL310 BECAUSE OF TFC IN THE VICINITY. SUBSEQUENTLY, THE FLT CONTINUED W/O FURTHER INCIDENT. CONTRIBUTING POINTS FOR CONSIDERATION: THIS AIRLINE COMPANY OPERATES MLG A AND MLG B. THE MLG B HAS A MORE SOPHISTICATED AUTOPLT SYS WITH ALT CAPTURE/HOLD, AS WELL AS DUAL ELECTRIC ALTIMETERS THAT ALWAYS READ THE SAME. THE MLG A DOES NOT, AND REQUIRES MUCH MORE CONCENTRATION, WITH A CROSS SCAN TO THE CAPT'S ELECTRIC ALTIMETER WITH RESPECT TO THE TRANSPONDER AND ENCODING. THE F/O'S BAROMETRIC ALTIMETER USUALLY READS 100-200 DIFFERENT (USUALLY HIGHER) AT ALT. IN THIS ACFT THE F/O'S ALTIMETER READ APPROX 150' LOWER (THAN THE CAPT'S). THE CAPT'S REMARKS ABOUT A LANDMARK DREW THE ATTN OF THE F/O AT A CRITICAL TIME--WHILE IN LEVEL OFF TO CRUISE ALT. THIS DISTR BROKE THE F/O'S SCAN OF BOTH ALTIMETERS TO OUTSIDE THE ACFT, ALLOWING THE ACFT TO DEVIATE ABOVE FL310. THE PREVIOUS LEG FLOWN BY THE F/O WAS IN AN MLG B. ALTHOUGH INSTRUMENTATION IN BOTH ACFT IS SIMILAR, THE MLG A DOES NOT HAVE THE MLG B AUTOPLT SYS THAT INCLUDES ALT CAPTURE HOLD. THIS REQUIRES CONCENTRATED EFFORT BY ALL PLTS TO DISTINGUISH THE DIFFERENCE ON DAYS OF MULTIPLE LEGS WITH ACFT CHANGES, ESPECIALLY FOR NEW F/O'S. WITH REGARD TO ATC, THE F/O HAD RECOGNIZED THE OVERSHOOT AT 31300' ON HIS BAROMETRIC ALTIMETER AND WAS RECOVERING WHEN ATC REPEATED THE CLRNC TO FL310. WHEN ATC NEXT REQUESTED THE FLT'S ALT, THE CAPT RESPONDED WITH 31500' (HIS ALTIMETER) THAT THE FLT WAS RECOVERING FROM AN OVERSHOOT. ANOTHER ATC VOICE REQUESTED THE FLT CALL LEVEL AT FL310, TO WHICH THE CAPT IMMEDIATELY RESPONDED 'LEVEL FL310,' AS THE ACFT HAD QUICKLY RECOVERED. ATC THEN STATED THE FLT HAD TFC AT FL330 AND 7 MI. THE CAPT ACKNOWLEDGED AND REPEATED 'LEVEL AT FL310.' NOTE: THIS COM BTWN ATC AND THE CAPT WAS CONTINUOUS AND UNINTERRUPTED, AND THE ENTIRE INCIDENT SPANNED APPROX 10-15 SECS. AGAIN, THE ACFT WAS LEVEL FL310, ACKNOWLEDGED AS SUCH PRIOR TO ATC'S ADVISORY OF THE TFC AT 7 MI AND FL330, AND DOES NOT APPEAR ANY INFRINGEMENT OF AIRSPACE TOOK PLACE WITH THAT TFC. THE FLT CONTINUED W/O FURTHER INCIDENT OR CONVERSATION FROM ATC WITH REGARD TO WHAT HAD TAKEN PLACE. RESOLUTION: FOR THIS PLT, THIS INCIDENT WAS A RARE OCCURRENCE, A BLOW TO PERSONAL STANDARDS AND PERFORMANCE, YET A HUMBLING, LEARNING EXPERIENCE. AS A NEW F/O WITH THIS AIRLINE, A CONTINUING LEARNING EFFORT AND DILIGENCE WITH RESPECT TO THE DIFFERING ACFT WILL ENHANCE MY PERSONAL STRIVE FOR ABSOLUTE DISCIPLINE AND PROFESSIONALISM IN FLYING I THINK THE CHAIN OF EVENTS SPEAK FOR THE CONTRIBUTING CAUSES FOR THIS INCIDENT, AND AGAIN, PERSONAL EFFORT WILL PREVENT A RECURRENCE. SUPPLEMENTAL INFO FROM ACN 94466: AT FL300 I CALLED OUT '1000 TO GO.' ALT ALERT SOUNDED. DIRECTED MY ATTN OUTSIDE THE ACFT. NEXT CALL WAS BY ZLA WITH, 'YOU WERE ONLY CLRED TO FL310...SAY YOUR ALT.' A GLANCE AT MY ALTIMETER SHOWED OUR ALT AT FL315. I IMMEDIATELY MOTIONED THE F/O TO LEVEL OFF AND AT THAT TIME THE ALT ALERT WENT OFF AND THE F/O RAPIDLY STARTED TO CORRECT BACK TO FL310. THE F/OS COMMENT WAS INTERESTING. HE SAID, 'I GUESS I THOUGHT I WAS IN AN MLG B AND IT WAS GOING TO LEVEL AT FL310 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.