A gulfstream iv on climb out overshot assigned altitude due to autothrottle malfunction.

Attributes
ACN	532210
Time
Date	200112
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sus.airport
State Reference	MO
Altitude	msl single value : 2500
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : t75.tracon
Operator	general aviation : corporate
Make Model Name	Gulfstream IV
Operating Under FAR Part	Part 91
Navigation In Use	other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 35 flight time total : 10000 flight time type : 85
ASRS Report	532210
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Events
Anomaly	aircraft equipment problem : less severe altitude deviation : overshoot non adherence : published procedure non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : altimeter other other : person 3
Resolutory Action	controller : issued new clearance flight crew : returned to assigned airspace
Consequence	Other
Supplementary
Problem Areas	Flight Crew Human Performance Aircraft
Primary Problem	Flight Crew Human Performance

Narrative:

On the previous departure (at ZZZ) we experienced the right engine accelerating rapidly on takeoff, which was indicating the autothrottle was not working quite as it should. So with the departure at sus we elected to perform a rated takeoff and to place the throttles at 1/2 throttle with maximum braking action to ensure the engines were both spooled up and providing power. The brakes were released and the autothrottles were engaged. The right engine again accelerated faster than the left. After liftoff and in the after takeoff checklist, the right engine temperature entered the caution area. The autothrottles were disengaged and retarded to normal operations. However, we were initially given 2500 ft restr on takeoff, but when we disengaged the autothrottles, we lost the altitude hold and inadvertently exceeded it, but arrested it at 3000 ft. The controller verified we were assigned 2500 ft, we confirmed that. He reclred us to 3000 ft. All indications were that there was no loss of separation between any aircraft. We were more focused on the engine parameters and failed to be as timely as we should have been on the altitude.

Original NASA ASRS Text

Title: A GULFSTREAM IV ON CLBOUT OVERSHOT ASSIGNED ALT DUE TO AUTOTHROTTLE MALFUNCTION.

Narrative: ON THE PREVIOUS DEP (AT ZZZ) WE EXPERIENCED THE R ENG ACCELERATING RAPIDLY ON TKOF, WHICH WAS INDICATING THE AUTOTHROTTLE WAS NOT WORKING QUITE AS IT SHOULD. SO WITH THE DEP AT SUS WE ELECTED TO PERFORM A RATED TKOF AND TO PLACE THE THROTTLES AT 1/2 THROTTLE WITH MAX BRAKING ACTION TO ENSURE THE ENGS WERE BOTH SPOOLED UP AND PROVIDING PWR. THE BRAKES WERE RELEASED AND THE AUTOTHROTTLES WERE ENGAGED. THE R ENG AGAIN ACCELERATED FASTER THAN THE L. AFTER LIFTOFF AND IN THE AFTER TKOF CHKLIST, THE R ENG TEMP ENTERED THE CAUTION AREA. THE AUTOTHROTTLES WERE DISENGAGED AND RETARDED TO NORMAL OPS. HOWEVER, WE WERE INITIALLY GIVEN 2500 FT RESTR ON TKOF, BUT WHEN WE DISENGAGED THE AUTOTHROTTLES, WE LOST THE ALT HOLD AND INADVERTENTLY EXCEEDED IT, BUT ARRESTED IT AT 3000 FT. THE CTLR VERIFIED WE WERE ASSIGNED 2500 FT, WE CONFIRMED THAT. HE RECLRED US TO 3000 FT. ALL INDICATIONS WERE THAT THERE WAS NO LOSS OF SEPARATION BTWN ANY ACFT. WE WERE MORE FOCUSED ON THE ENG PARAMETERS AND FAILED TO BE AS TIMELY AS WE SHOULD HAVE BEEN ON THE ALT.

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.