A320 flight crew reports EPR rollback during takeoff from 1.40 to 1.20 and then return to 1.40 after...

Attributes
ACN	747378
Time
Date	200707
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 1200
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	747378
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
ASRS Report	747387
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	aircraft equipment other aircraft equipment : epr gauge other flight crewa
Resolutory Action	flight crew : landed as precaution other
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

On departure #2 engine rolled back from takeoff. EPR of 1.40 to less than 1.20 EPR at 400 ft AGL with significant yaw due to power loss. Engine power reestablished on its own within 10 seconds. Continued climb and SID to burn some fuel and make contact with maintenance. After speaking with maintenance first officer and myself made the decision to return to ZZZ. After coordinating with operations and ATC we notified flight attendants and passenger of diversion; accomplished QRH checklist for overweight landing of 146200 pounds (142198 pounds maximum) normal approach and landing was made at flaps full and a touchdown rate of less than 100 FPM. Normal taxi and shutdown was accomplished. Callback conversation with reporter revealed the following information: the aircraft sat for several days after the incident during which time maintenance did not find any definitive cause for the anomaly. Finally a decision was made to change the fuel control unit and return the aircraft to service. No further problems were reported.

Original NASA ASRS Text

Title: A320 FLT CREW REPORTS EPR ROLLBACK DURING TKOF FROM 1.40 TO 1.20 AND THEN RETURN TO 1.40 AFTER 10 SECONDS. AFTER DISCUSSION WITH MAINTENANCE FLT CREW ELECTS TO RETURN TO DEPARTURE ARPT FOR OVERWEIGHT LANDING.

Narrative: ON DEP #2 ENG ROLLED BACK FROM TKOF. EPR OF 1.40 TO LESS THAN 1.20 EPR AT 400 FT AGL WITH SIGNIFICANT YAW DUE TO PWR LOSS. ENG PWR REESTABLISHED ON ITS OWN WITHIN 10 SECONDS. CONTINUED CLB AND SID TO BURN SOME FUEL AND MAKE CONTACT WITH MAINT. AFTER SPEAKING WITH MAINT FO AND MYSELF MADE THE DECISION TO RETURN TO ZZZ. AFTER COORDINATING WITH OPS AND ATC WE NOTIFIED FLT ATTENDANTS AND PAX OF DIVERSION; ACCOMPLISHED QRH CHKLIST FOR OVERWT LNDG OF 146200 LBS (142198 LBS MAX) NORMAL APCH AND LNDG WAS MADE AT FLAPS FULL AND A TOUCHDOWN RATE OF LESS THAN 100 FPM. NORMAL TAXI AND SHUTDOWN WAS ACCOMPLISHED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE ACFT SAT FOR SEVERAL DAYS AFTER THE INCIDENT DURING WHICH TIME MAINTENANCE DID NOT FIND ANY DEFINITIVE CAUSE FOR THE ANOMALY. FINALLY A DECISION WAS MADE TO CHANGE THE FUEL CONTROL UNIT AND RETURN THE ACFT TO SERVICE. NO FURTHER PROBLEMS WERE REPORTED.

Data retrieved from NASA's ASRS site as of January 2009 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.

A320 flight crew reports EPR rollback during takeoff from 1.40 to 1.20 and then return to 1.40 after 10 seconds. After discussion with maintenance flight crew elects to return to departure airport for overweight landing.