Narrative:

Flight leg from atl to chs. Cruise altitude FL290. WX clear, visibility unlimited. During climb out of atl, flight attendants notified us of a passenger service problem (no water, thus no hot beverage available) and asked us to make a PA. This occurred simultaneously with an ATC frequency change and about the same time we passed FL180. As a result of these 2 events, both pilots missed resetting altimeters to 29.92. Altimeters were set at 30.45. Aircraft only at cruise altitude about 10 mins and talked to 2 jax center sector controllers. During descent to FL260, ZJX asked us to report level at FL260 but gave us no additional information. At about FL264 I saw an mlt aircraft at our 11:30 position, approaching and passing beneath us and about 1/2 mi to our left. At level off, ZJX questioned our altimeter setting. We immediately reset both altimeters to 29.92 and corrected the aircraft cruise altitude by about 300-400 ft. While acknowledging the cause of our reduced vertical separation with the mlt was our incorrectly set altimeters, we both discussed the center's lack of calling the traffic to our attention and not questioning our altimeter setting at cruise altitude, even though we evidently passed through 2 sectors. Supplemental information from acn 225722: on the climb out, both pilots were distracted by a passenger problem and radio calls and neglected to perform our climb checks. Our altimeters remained at 30.45.

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Original NASA ASRS Text

Title: FLC OF ACR MLG ACFT OVERSHOT CLB ALT DUE TO NOT RESETTING THE ALT PASSING FL180 RESULTING IN LTSS WITH ANOTHER ACFT.

Narrative: FLT LEG FROM ATL TO CHS. CRUISE ALT FL290. WX CLR, VISIBILITY UNLIMITED. DURING CLBOUT OF ATL, FLT ATTENDANTS NOTIFIED US OF A PAX SVC PROBLEM (NO WATER, THUS NO HOT BEVERAGE AVAILABLE) AND ASKED US TO MAKE A PA. THIS OCCURRED SIMULTANEOUSLY WITH AN ATC FREQ CHANGE AND ABOUT THE SAME TIME WE PASSED FL180. AS A RESULT OF THESE 2 EVENTS, BOTH PLTS MISSED RESETTING ALTIMETERS TO 29.92. ALTIMETERS WERE SET AT 30.45. ACFT ONLY AT CRUISE ALT ABOUT 10 MINS AND TALKED TO 2 JAX CTR SECTOR CTLRS. DURING DSCNT TO FL260, ZJX ASKED US TO RPT LEVEL AT FL260 BUT GAVE US NO ADDITIONAL INFO. AT ABOUT FL264 I SAW AN MLT ACFT AT OUR 11:30 POS, APCHING AND PASSING BENEATH US AND ABOUT 1/2 MI TO OUR L. AT LEVEL OFF, ZJX QUESTIONED OUR ALTIMETER SETTING. WE IMMEDIATELY RESET BOTH ALTIMETERS TO 29.92 AND CORRECTED THE ACFT CRUISE ALT BY ABOUT 300-400 FT. WHILE ACKNOWLEDGING THE CAUSE OF OUR REDUCED VERT SEPARATION WITH THE MLT WAS OUR INCORRECTLY SET ALTIMETERS, WE BOTH DISCUSSED THE CTR'S LACK OF CALLING THE TFC TO OUR ATTN AND NOT QUESTIONING OUR ALTIMETER SETTING AT CRUISE ALT, EVEN THOUGH WE EVIDENTLY PASSED THROUGH 2 SECTORS. SUPPLEMENTAL INFO FROM ACN 225722: ON THE CLBOUT, BOTH PLTS WERE DISTRACTED BY A PAX PROBLEM AND RADIO CALLS AND NEGLECTED TO PERFORM OUR CLB CHKS. OUR ALTIMETERS REMAINED AT 30.45.

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.