Air carrier crew fails to engage proper mode after altimeter reset below FL180.

Attributes
ACN	192418
Time
Date	199110
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : air
State Reference	OH
Altitude	msl bound lower : 10000 msl bound upper : 10300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pit
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : cfi pilot : flight engineer pilot : instrument
Experience	flight time last 90 days : 25 flight time total : 10500 flight time type : 500
ASRS Report	192418
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	altitude deviation : undershoot non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

When descending below FL180, my altimeter was set to the proper barometric pressure, but due to advanced cockpit design, the push button which controls the altimeter display was inadvertently left in 'standard'. As a result, 29.92 was the active setting when leveling at 10000 ft. This resulted in a level off 200-300 ft high. The situation was recognized when the before landing checklist was completed. 2 factors led to this problem. Cockpit design which requires crew to set the proper barometric pressure and also requires that a push button be selected in the proper mode. The 2 modes available are 'standard' which is used at and above FL180 and 'qnh' which sets the altimeter to the pressure set by the crew. The second factor is that our procedure is to maintain a sterile cockpit and perform the before landing checklist at approximately 10000 ft. This means that the crew's attention may be diverted between FL180 and 10000 ft. In addition, delaying the checklist means that checking for proper modes is not accomplished until reaching 10000 ft. As a result, I will start maintaining a sterile cockpit and accomplish the checklist at FL180 instead of 10000 ft. You can never be too early!

Original NASA ASRS Text

Title: ACR CREW FAILS TO ENGAGE PROPER MODE AFTER ALTIMETER RESET BELOW FL180.

Narrative: WHEN DSNDING BELOW FL180, MY ALTIMETER WAS SET TO THE PROPER BAROMETRIC PRESSURE, BUT DUE TO ADVANCED COCKPIT DESIGN, THE PUSH BUTTON WHICH CTLS THE ALTIMETER DISPLAY WAS INADVERTENTLY LEFT IN 'STD'. AS A RESULT, 29.92 WAS THE ACTIVE SETTING WHEN LEVELING AT 10000 FT. THIS RESULTED IN A LEVEL OFF 200-300 FT HIGH. THE SITUATION WAS RECOGNIZED WHEN THE BEFORE LNDG CHKLIST WAS COMPLETED. 2 FACTORS LED TO THIS PROBLEM. COCKPIT DESIGN WHICH REQUIRES CREW TO SET THE PROPER BAROMETRIC PRESSURE AND ALSO REQUIRES THAT A PUSH BUTTON BE SELECTED IN THE PROPER MODE. THE 2 MODES AVAILABLE ARE 'STD' WHICH IS USED AT AND ABOVE FL180 AND 'QNH' WHICH SETS THE ALTIMETER TO THE PRESSURE SET BY THE CREW. THE SECOND FACTOR IS THAT OUR PROC IS TO MAINTAIN A STERILE COCKPIT AND PERFORM THE BEFORE LNDG CHKLIST AT APPROX 10000 FT. THIS MEANS THAT THE CREW'S ATTN MAY BE DIVERTED BTWN FL180 AND 10000 FT. IN ADDITION, DELAYING THE CHKLIST MEANS THAT CHKING FOR PROPER MODES IS NOT ACCOMPLISHED UNTIL REACHING 10000 FT. AS A RESULT, I WILL START MAINTAINING A STERILE COCKPIT AND ACCOMPLISH THE CHKLIST AT FL180 INSTEAD OF 10000 FT. YOU CAN NEVER BE TOO EARLY!

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.