Altitude deviation altitude overshot in descent.

Attributes
ACN	307340
Time
Date	199506
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : zob
State Reference	OH
Altitude	msl bound lower : 30500 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 150 flight time total : 9000 flight time type : 500
ASRS Report	307340
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot non adherence : published procedure non adherence : clearance other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : became reoriented other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation other

Narrative:

Aircraft was cleared to descend from FL330 to FL310. First officer failed to make 1000 ft warning call. Captain was engaged in conversation. First officer noted altitude at FL314. Aircraft descended through FL310 to FL305. At FL307, first officer called out the error. Altitude alert chime sounded immediately. First officer had some confusion reading drum pointer altimeter. The drum 1000 ft index mark disagreed with the pointer by approximately 300 ft, so that with the pointer at zero hundred ft, the drum index showed 31300 ft. This was subsequently written up in aircraft maintenance log. Center called out the deviation immediately after first officer called it out.

Original NASA ASRS Text

Title: ALTDEV ALT OVERSHOT IN DSCNT.

Narrative: ACFT WAS CLRED TO DSND FROM FL330 TO FL310. FO FAILED TO MAKE 1000 FT WARNING CALL. CAPT WAS ENGAGED IN CONVERSATION. FO NOTED ALT AT FL314. ACFT DSNDED THROUGH FL310 TO FL305. AT FL307, FO CALLED OUT THE ERROR. ALT ALERT CHIME SOUNDED IMMEDIATELY. FO HAD SOME CONFUSION READING DRUM POINTER ALTIMETER. THE DRUM 1000 FT INDEX MARK DISAGREED WITH THE POINTER BY APPROX 300 FT, SO THAT WITH THE POINTER AT ZERO HUNDRED FT, THE DRUM INDEX SHOWED 31300 FT. THIS WAS SUBSEQUENTLY WRITTEN UP IN ACFT MAINT LOG. CTR CALLED OUT THE DEV IMMEDIATELY AFTER FO CALLED IT OUT.

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.