An A320 crew experienced a sudden EPR drop followed by EPR recovery and normal operation.

Attributes
ACN	640753
Time
Date	200412
Day	Thu
Place
Locale Reference	atc facility : zau.artcc
State Reference	IL
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	artcc : zau.artcc
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Experience	flight time last 90 days : 240 flight time total : 17000 flight time type : 3500
ASRS Report	640753
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : epr change, noise
Resolutory Action	none taken : anomaly accepted
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Passing through approximately 10500 ft, got a bang and slight yaw. Engine #2 EPR dropped down to 1.3 from climb EPR and almost immediately went back to normal. No ecams or other abnormal parameters noted. Engine response was normal. Flight attendants and passenger reported hearing the bang. There was also light turbulence during the event. Contacted maintenance. Based on no history and now normal engine, elected to proceed to las. Notified dispatch and filled out the flameout/compressor stall form called for in the flight manual and left for maintenance.

Original NASA ASRS Text

Title: AN A320 CREW EXPERIENCED A SUDDEN EPR DROP FOLLOWED BY EPR RECOVERY AND NORMAL OP.

Narrative: PASSING THROUGH APPROX 10500 FT, GOT A BANG AND SLIGHT YAW. ENG #2 EPR DROPPED DOWN TO 1.3 FROM CLB EPR AND ALMOST IMMEDIATELY WENT BACK TO NORMAL. NO ECAMS OR OTHER ABNORMAL PARAMETERS NOTED. ENG RESPONSE WAS NORMAL. FLT ATTENDANTS AND PAX RPTED HEARING THE BANG. THERE WAS ALSO LIGHT TURB DURING THE EVENT. CONTACTED MAINT. BASED ON NO HISTORY AND NOW NORMAL ENG, ELECTED TO PROCEED TO LAS. NOTIFIED DISPATCH AND FILLED OUT THE FLAMEOUT/COMPRESSOR STALL FORM CALLED FOR IN THE FLT MANUAL AND LEFT FOR MAINT.

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.