Altitude deviation excursion from assigned.

Attributes
ACN	119844
Time
Date	198908
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : lny
State Reference	HI
Altitude	msl bound lower : 13000 msl bound upper : 14000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute airway : v2
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 103 flight time total : 6500 flight time type : 850
ASRS Report	119844
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 350 flight time total : 7200 flight time type : 4500
ASRS Report	119854
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : returned to intended course or assigned course flight crew : overcame equipment problem none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Air carrier xx, en route hnl direct ogg, along V2, aug/mon/89. Leveled off at 13,000 MSL assigned and engaged autoplt with pitch wheel on zero (altitude hold engaged). We then recorded the daily engine readings (less than 1 minute) with PF reading and PNF writing, then returned attention to instruments/navigation. 'Noted' with disbelief we were ascending through 14,000' with autoplt still engaged. Disconnected autoplt and rapidly descended to 13,000' MSL. There was no call from center during or after excursion. Write-up from previous day aug/wed/89, 'autoplt will not hold level flight'. Maintenance replaced pitch axis computer. Because of the type altimeter installed, the altitude excursion was not immediately recognized but had to be verified by x-checking other instruments, ie, vertical speed indicator, airspeed.

Original NASA ASRS Text

Title: ALT DEVIATION EXCURSION FROM ASSIGNED.

Narrative: ACR XX, ENRTE HNL DIRECT OGG, ALONG V2, AUG/MON/89. LEVELED OFF AT 13,000 MSL ASSIGNED AND ENGAGED AUTOPLT WITH PITCH WHEEL ON ZERO (ALT HOLD ENGAGED). WE THEN RECORDED THE DAILY ENGINE READINGS (LESS THAN 1 MINUTE) WITH PF READING AND PNF WRITING, THEN RETURNED ATTN TO INSTRUMENTS/NAVIGATION. 'NOTED' WITH DISBELIEF WE WERE ASCENDING THROUGH 14,000' WITH AUTOPLT STILL ENGAGED. DISCONNECTED AUTOPLT AND RAPIDLY DESCENDED TO 13,000' MSL. THERE WAS NO CALL FROM CENTER DURING OR AFTER EXCURSION. WRITE-UP FROM PREVIOUS DAY AUG/WED/89, 'AUTOPLT WILL NOT HOLD LEVEL FLT'. MAINT REPLACED PITCH AXIS COMPUTER. BECAUSE OF THE TYPE ALTIMETER INSTALLED, THE ALT EXCURSION WAS NOT IMMEDIATELY RECOGNIZED BUT HAD TO BE VERIFIED BY X-CHECKING OTHER INSTRUMENTS, IE, VERTICAL SPEED INDICATOR, AIRSPEED.

Data retrieved from NASA's ASRS site as of August 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.