Altitude deviation altitude undershot. Altitude crossing restriction not met.

Attributes
ACN	189750
Time
Date	199109
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : cgt
State Reference	IL
Altitude	msl bound lower : 10000 msl bound upper : 10400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
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
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 100 flight time total : 6000 flight time type : 700
ASRS Report	189750
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 7000 flight time type : 1000
ASRS Report	189662
Events
Anomaly	altitude deviation : crossing restriction not met altitude deviation : undershoot non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

First officer flying and we were cleared to cross 45 east of cgt at 10000 ft. At about 50 east I saw we were passing through 10600 ft and I had local altimeter set. Not noticing we stopped at 10400 (leveled off), center called us at 40 east to question our altitude and then we discovered the first officer had inadvertently reset his altimeter button to standard (29.92), so his autoplt leveled us off at 10400 ft MSL. Center said no conflict resulted. We tried to find out why the first officer's altimeter was back at standard and not the local altimeter as had been set during our preliminary landing checklist. On a subsequent flight, the first officer found that he was punching the altimeter button when he wanted the airport button to display airports on navigation display. So, as always, I need to always watch the aircraft level off completely to the end, all the way to 10000 ft. I may have done that this time and the aircraft may have climbed back to 10400 ft when he hit the altitude button back to standard, not sure. Did not hear any warning horns though in that case. Again, complete the level off before allowing my attention to be diverted. I usually do, not sure why this time.

Original NASA ASRS Text

Title: ALT DEV ALT UNDERSHOT. ALT XING RESTRICTION NOT MET.

Narrative: FO FLYING AND WE WERE CLRED TO CROSS 45 E OF CGT AT 10000 FT. AT ABOUT 50 E I SAW WE WERE PASSING THROUGH 10600 FT AND I HAD LCL ALTIMETER SET. NOT NOTICING WE STOPPED AT 10400 (LEVELED OFF), CENTER CALLED US AT 40 E TO QUESTION OUR ALT AND THEN WE DISCOVERED THE FO HAD INADVERTENTLY RESET HIS ALTIMETER BUTTON TO STD (29.92), SO HIS AUTOPLT LEVELED US OFF AT 10400 FT MSL. CENTER SAID NO CONFLICT RESULTED. WE TRIED TO FIND OUT WHY THE FO'S ALTIMETER WAS BACK AT STD AND NOT THE LCL ALTIMETER AS HAD BEEN SET DURING OUR PRELIMINARY LNDG CHKLIST. ON A SUBSEQUENT FLT, THE FO FOUND THAT HE WAS PUNCHING THE ALTIMETER BUTTON WHEN HE WANTED THE ARPT BUTTON TO DISPLAY ARPTS ON NAV DISPLAY. SO, AS ALWAYS, I NEED TO ALWAYS WATCH THE ACFT LEVEL OFF COMPLETELY TO THE END, ALL THE WAY TO 10000 FT. I MAY HAVE DONE THAT THIS TIME AND THE ACFT MAY HAVE CLBED BACK TO 10400 FT WHEN HE HIT THE ALT BUTTON BACK TO STD, NOT SURE. DID NOT HEAR ANY WARNING HORNS THOUGH IN THAT CASE. AGAIN, COMPLETE THE LEVEL OFF BEFORE ALLOWING MY ATTN TO BE DIVERTED. I USUALLY DO, NOT SURE WHY THIS TIME.

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.