Pilot overshoots altitude reading erroneous altimeter.

Attributes
ACN	299120
Time
Date	199503
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : ord
State Reference	IL
Altitude	msl bound lower : 2500 msl bound upper : 2800
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord tower : ojc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 91
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : cfi
Experience	flight time last 90 days : 240 flight time total : 4450 flight time type : 2850
ASRS Report	299120
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot non adherence : clearance
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : overcame equipment problem
Consequence	Other Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

During a position flight from ord to cgx, ATC assigned us altitude of 2500 ft MSL. I captain (PF) leveled off at 2500 ft, the first officer remarked, 'altitude.' the altimeter settings were both correct, but mine read 2500 ft and the first officer's read 2800 ft. Also, a variation in airspeed of 30 KIAS was noted. Upon landing at cgx 2 gaskets were found on the floor of the cockpit from the airspeed indicator's glass. This was the third leg this day in the same aircraft. With no previous problems noted.

Original NASA ASRS Text

Title: PLT OVERSHOOTS ALT READING ERRONEOUS ALTIMETER.

Narrative: DURING A POS FLT FROM ORD TO CGX, ATC ASSIGNED US ALTITUDE OF 2500 FT MSL. I CAPT (PF) LEVELED OFF AT 2500 FT, THE FO REMARKED, 'ALT.' THE ALTIMETER SETTINGS WERE BOTH CORRECT, BUT MINE READ 2500 FT AND THE FO'S READ 2800 FT. ALSO, A VARIATION IN AIRSPD OF 30 KIAS WAS NOTED. UPON LNDG AT CGX 2 GASKETS WERE FOUND ON THE FLOOR OF THE COCKPIT FROM THE AIRSPD INDICATOR'S GLASS. THIS WAS THE THIRD LEG THIS DAY IN THE SAME ACFT. WITH NO PREVIOUS PROBS NOTED.

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.