Aircraft returns to land due to engine power indications.

Attributes
ACN	284086
Time
Date	199409
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : iad
State Reference	VA
Altitude	msl bound lower : 7000 msl bound upper : 7000
Environment
Flight Conditions	Mixed
Light	Dawn
Aircraft 1
Controlling Facilities	tracon : iad
Operator	common carrier : air carrier
Make Model Name	Jetstream 32
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial climbout : intermediate altitude other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 3500 flight time type : 1700
ASRS Report	284086
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	none taken : unable
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

On takeoff climb the left engine started torque fluctuations. I called for the quick reference checklist (as is our company procedure). After calling for the checklist, and leveling the aircraft at 8000 ft MSL, torque on the left engine fell to 20 percent and egt climbed to 680 degrees centigrade (above maximum egt). The 'QRH' checklist was performed, during which it was determined that the temperature -- torque limiting computer was the probable cause, and it was switched off as per the checklist. After the 'ttl' was switched off, all engine indications and functions appeared to return to normal. I made the decision to return to iad for landing with both engines running, and my first officer suggested we have crash equipment standing by, where the engine could no longer be considered 100 percent reliable and an ILS to 300 ft on 1/2 mi was to be made. I agreed and we did so. All appropriate checklist were performed prior to landing, and the landing was successful. Clearing the runway, after appropriate checklists were performed the left engine was shut down manually during the taxi to our gate, to avoid other possible problems.

Original NASA ASRS Text

Title: ACFT RETURNS TO LAND DUE TO ENG PWR INDICATIONS.

Narrative: ON TKOF CLB THE L ENG STARTED TORQUE FLUCTUATIONS. I CALLED FOR THE QUICK REF CHKLIST (AS IS OUR COMPANY PROC). AFTER CALLING FOR THE CHKLIST, AND LEVELING THE ACFT AT 8000 FT MSL, TORQUE ON THE L ENG FELL TO 20 PERCENT AND EGT CLBED TO 680 DEGS CENTIGRADE (ABOVE MAX EGT). THE 'QRH' CHKLIST WAS PERFORMED, DURING WHICH IT WAS DETERMINED THAT THE TEMP -- TORQUE LIMITING COMPUTER WAS THE PROBABLE CAUSE, AND IT WAS SWITCHED OFF AS PER THE CHKLIST. AFTER THE 'TTL' WAS SWITCHED OFF, ALL ENG INDICATIONS AND FUNCTIONS APPEARED TO RETURN TO NORMAL. I MADE THE DECISION TO RETURN TO IAD FOR LNDG WITH BOTH ENGS RUNNING, AND MY FO SUGGESTED WE HAVE CRASH EQUIP STANDING BY, WHERE THE ENG COULD NO LONGER BE CONSIDERED 100 PERCENT RELIABLE AND AN ILS TO 300 FT ON 1/2 MI WAS TO BE MADE. I AGREED AND WE DID SO. ALL APPROPRIATE CHKLIST WERE PERFORMED PRIOR TO LNDG, AND THE LNDG WAS SUCCESSFUL. CLRING THE RWY, AFTER APPROPRIATE CHKLISTS WERE PERFORMED THE L ENG WAS SHUT DOWN MANUALLY DURING THE TAXI TO OUR GATE, TO AVOID OTHER POSSIBLE PROBS.

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.