Narrative:

At XX00Z VFR from osh to mqj, indianapolis, in. Working chicago center on flight following approximately 25 east of chicago at 17500 MSL engine acted like it blew a turbo. Chicago center gave us a heading to gary airport to descend to 9.0 then to 4.5. No emergency declared. At gary overhead 4.5 MSL engine stabilized and I decided to fly to laf. All gauges in green. 5 mi north of rensselaer, in, airport engine developed roughness and partial loss of power at XX22Z squawked 7700. Center gave us a vector to rensselaer airport 3 mi and 180 degrees for safety, I landed on grass farm 2 mi north of airport. After landing I relayed safe landing no damage no injuries to chicago center.

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Original NASA ASRS Text

Title: ENG ROUGHNESS CREATES NEED FOR EMER TO BE DECLARED. OFF ARPT EMER LNDG PERFORMED AFTER FLT ASSIST FROM ZAU CTR.

Narrative: AT XX00Z VFR FROM OSH TO MQJ, INDIANAPOLIS, IN. WORKING CHICAGO CTR ON FLT FOLLOWING APPROX 25 E OF CHICAGO AT 17500 MSL ENG ACTED LIKE IT BLEW A TURBO. CHICAGO CTR GAVE US A HDG TO GARY ARPT TO DSND TO 9.0 THEN TO 4.5. NO EMER DECLARED. AT GARY OVERHEAD 4.5 MSL ENG STABILIZED AND I DECIDED TO FLY TO LAF. ALL GAUGES IN GREEN. 5 MI N OF RENSSELAER, IN, ARPT ENG DEVELOPED ROUGHNESS AND PARTIAL LOSS OF PWR AT XX22Z SQUAWKED 7700. CTR GAVE US A VECTOR TO RENSSELAER ARPT 3 MI AND 180 DEGS FOR SAFETY, I LANDED ON GRASS FARM 2 MI N OF ARPT. AFTER LNDG I RELAYED SAFE LNDG NO DAMAGE NO INJURIES TO CHICAGO CTR.

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.