A fokker 100 flight crew declared an emergency and return to clt due to an engine surging.

Attributes
ACN	457916
Time
Date	199912
Day	Fri
Local Time Of Day	0601 To 1200
Place
State Reference	SC
Altitude	msl single value : 21500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zjx.artcc
Operator	common carrier : air carrier
Make Model Name	Fokker 100
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
ASRS Report	457916
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : engine instrument other flight crewa other flight crewb
Resolutory Action	flight crew : diverted to another airport flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Climbing through FL215, autoplt, autothrottles on, #1 (left) engine began to surge. No parameters were exceeded, but I elected to return to clt, our airport of departure. Surges continued with a frequency of about one every 7-10 seconds. Intensity of 7-11% N1, change (with autothrottle off now). Requested emergency equipment standing by in case of further problems, which may have dictated declaring an emergency, but fortunately that did not occur and return to departure field was uneventful. Thanks to ZJX, clt ATC, clt crash fire rescue equipment, company personnel on ground clt, and dispatch.

Original NASA ASRS Text

Title: A FOKKER 100 FLC DECLARED AN EMER AND RETURN TO CLT DUE TO AN ENG SURGING.

Narrative: CLBING THROUGH FL215, AUTOPLT, AUTOTHROTTLES ON, #1 (L) ENG BEGAN TO SURGE. NO PARAMETERS WERE EXCEEDED, BUT I ELECTED TO RETURN TO CLT, OUR ARPT OF DEP. SURGES CONTINUED WITH A FREQ OF ABOUT ONE EVERY 7-10 SECONDS. INTENSITY OF 7-11% N1, CHANGE (WITH AUTOTHROTTLE OFF NOW). REQUESTED EMER EQUIP STANDING BY IN CASE OF FURTHER PROBS, WHICH MAY HAVE DICTATED DECLARING AN EMER, BUT FORTUNATELY THAT DID NOT OCCUR AND RETURN TO DEP FIELD WAS UNEVENTFUL. THANKS TO ZJX, CLT ATC, CLT CFR, COMPANY PERSONNEL ON GND CLT, AND DISPATCH.

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.