Medium large transport in climb overshot assigned altitude FL230.

Attributes
ACN	178641
Time
Date	199105
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : vuz
State Reference	AL
Altitude	msl bound lower : 23000 msl bound upper : 23400
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : ztl
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : commercial pilot : instrument
Experience	flight time last 90 days : 180 flight time total : 12000 flight time type : 500
ASRS Report	178641
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 230 flight time total : 4000 flight time type : 1400
ASRS Report	178933
Events
Anomaly	aircraft equipment problem : less severe conflict : airborne less severe non adherence : required legal separation non adherence : clearance other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : regained aircraft control flight crew : overcame equipment problem
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Given climb to FL380 then immediate cancel and level off at FL230. Autoplt flying aircraft and during level off TCAS blasted out, 'traffic,' and then, 'descend...' I took yoke and clicked off autoplt to start down. (TCAS gave 2000 FPM descent resolution.) aircraft pitched up due to excessive nose up trim. In the seconds it took to overcome nose up trim and get aircraft started down, the aircraft climbed about 400' causing traffic conflict. Automatic throttles compounded problem going to full climb power to overcome initial speed drop. Problem caused by excessive nose up trim by autoplt. Also problem compounded by automatic throttles initially adding power because of airspeed slightly low. If the TCAS had not sounded alert, the level off at FL230 would have solved the problem as ATC knew it would. TCAS caused a needless conflict and problem. When autoplt is out of trim. The seconds it takes to transition to manual control can cause aircraft to initially depart an altitude in the wrong direction.

Original NASA ASRS Text

Title: MLG IN CLIMB OVERSHOT ASSIGNED ALT FL230.

Narrative: GIVEN CLB TO FL380 THEN IMMEDIATE CANCEL AND LEVEL OFF AT FL230. AUTOPLT FLYING ACFT AND DURING LEVEL OFF TCAS BLASTED OUT, 'TFC,' AND THEN, 'DSND...' I TOOK YOKE AND CLICKED OFF AUTOPLT TO START DOWN. (TCAS GAVE 2000 FPM DSNT RESOLUTION.) ACFT PITCHED UP DUE TO EXCESSIVE NOSE UP TRIM. IN THE SECS IT TOOK TO OVERCOME NOSE UP TRIM AND GET ACFT STARTED DOWN, THE ACFT CLBED ABOUT 400' CAUSING TFC CONFLICT. AUTO THROTTLES COMPOUNDED PROB GOING TO FULL CLB PWR TO OVERCOME INITIAL SPD DROP. PROB CAUSED BY EXCESSIVE NOSE UP TRIM BY AUTOPLT. ALSO PROB COMPOUNDED BY AUTO THROTTLES INITIALLY ADDING PWR BECAUSE OF AIRSPD SLIGHTLY LOW. IF THE TCAS HAD NOT SOUNDED ALERT, THE LEVEL OFF AT FL230 WOULD HAVE SOLVED THE PROB AS ATC KNEW IT WOULD. TCAS CAUSED A NEEDLESS CONFLICT AND PROB. WHEN AUTOPLT IS OUT OF TRIM. THE SECS IT TAKES TO TRANSITION TO MANUAL CTL CAN CAUSE ACFT TO INITIALLY DEPART AN ALT IN THE WRONG DIRECTION.

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.