Altitude deviation altitude excursion.

Attributes
ACN	240154
Time
Date	199304
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : sjt
State Reference	TX
Altitude	msl bound lower : 5000 msl bound upper : 24000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zfw
Operator	general aviation : corporate
Make Model Name	Medium Transport
Flight Phase	cruise other cruise other descent other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 55 flight time total : 10100 flight time type : 950
ASRS Report	240154
Person 2
Affiliation	Other
Function	other personnel other
Qualification	pilot : atp
Experience	flight time last 90 days : 90 flight time total : 10900 flight time type : 1300
ASRS Report	240267
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot altitude deviation : excursion from assigned altitude non adherence : clearance other anomaly other
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	Pilot Deviation

Narrative:

PF was hire pilot performing maintenance acceptance checks as part of pre-purchase. Total failure of electric stabilizer trim (normal and emergency) caused confusion and alarm and while troubleshooting the problem, allowed the aircraft to descend to approximately 23500 ft from assigned altitude of 24000 ft. Control pressures on the yoke were heavy and contributed to the altitude 'bust.' I took control of the aircraft and replaced the hire pilot with the regular sic. ATC was advised of our trim problem and asked for clearance to return to dallas love field. No special handling was requested other than a more gradual descent profile than normal to keep airspeed and control pressures to a minimum. A descent clearance to 11000 ft was received, followed by a clearance to descend further to 5000 ft. The 5000 ft clearance was perceived to be accommodating our request for an early and gradual descent profile. All clrncs were read back. Frequency change and reporting we were descending to 5000 ft was met with confusion by new controller who instructed us to return to previous frequency. When doing so, previous controller questioned our assigned altitude which led me to believe he was not aware of the 5000 ft clearance previously issued.

Original NASA ASRS Text

Title: ALTDEV ALT EXCURSION.

Narrative: PF WAS HIRE PLT PERFORMING MAINT ACCEPTANCE CHKS AS PART OF PRE-PURCHASE. TOTAL FAILURE OF ELECTRIC STABILIZER TRIM (NORMAL AND EMER) CAUSED CONFUSION AND ALARM AND WHILE TROUBLESHOOTING THE PROB, ALLOWED THE ACFT TO DSND TO APPROX 23500 FT FROM ASSIGNED ALT OF 24000 FT. CTL PRESSURES ON THE YOKE WERE HVY AND CONTRIBUTED TO THE ALT 'BUST.' I TOOK CTL OF THE ACFT AND REPLACED THE HIRE PLT WITH THE REGULAR SIC. ATC WAS ADVISED OF OUR TRIM PROB AND ASKED FOR CLRNC TO RETURN TO DALLAS LOVE FIELD. NO SPECIAL HANDLING WAS REQUESTED OTHER THAN A MORE GRADUAL DSCNT PROFILE THAN NORMAL TO KEEP AIRSPD AND CTL PRESSURES TO A MINIMUM. A DSCNT CLRNC TO 11000 FT WAS RECEIVED, FOLLOWED BY A CLRNC TO DSND FURTHER TO 5000 FT. THE 5000 FT CLRNC WAS PERCEIVED TO BE ACCOMMODATING OUR REQUEST FOR AN EARLY AND GRADUAL DSCNT PROFILE. ALL CLRNCS WERE READ BACK. FREQ CHANGE AND RPTING WE WERE DSNDING TO 5000 FT WAS MET WITH CONFUSION BY NEW CTLR WHO INSTRUCTED US TO RETURN TO PREVIOUS FREQ. WHEN DOING SO, PREVIOUS CTLR QUESTIONED OUR ASSIGNED ALT WHICH LED ME TO BELIEVE HE WAS NOT AWARE OF THE 5000 FT CLRNC PREVIOUSLY ISSUED.

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.