C210 pilot has rough engine on reaching 10000 ft after departure. Return land.

Attributes
ACN	330058
Time
Date	199603
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : bil
State Reference	MT
Altitude	msl bound lower : 10000 msl bound upper : 10000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc tracon : gtf
Operator	general aviation : personal
Make Model Name	Cessna 210 Centurion / Turbo Centurion 210C, 210D
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude landing other
Flight Plan	IFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 12 flight time total : 227 flight time type : 5
ASRS Report	330058
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	flight crew : declared emergency other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

I had just departed bil for vel. I was just reaching 10000 ft and my engine in the centurion 210 I was flying began running rough. I requested a 180 degree turn back to bil. Then I couldn't hold altitude and descended to approximately 8000 ft. I then got the aircraft stabilized and asked for a heading from approach who I was then handed to by center. They gave me a heading of 340 degrees which I flew through because I was overworked. I then regained my heading and with lots of help from ATC I got the aircraft back to billings safely.

Original NASA ASRS Text

Title: C210 PLT HAS ROUGH ENG ON REACHING 10000 FT AFTER DEP. RETURN LAND.

Narrative: I HAD JUST DEPARTED BIL FOR VEL. I WAS JUST REACHING 10000 FT AND MY ENG IN THE CENTURION 210 I WAS FLYING BEGAN RUNNING ROUGH. I REQUESTED A 180 DEG TURN BACK TO BIL. THEN I COULDN'T HOLD ALT AND DSNDED TO APPROX 8000 FT. I THEN GOT THE ACFT STABILIZED AND ASKED FOR A HDG FROM APCH WHO I WAS THEN HANDED TO BY CTR. THEY GAVE ME A HDG OF 340 DEGS WHICH I FLEW THROUGH BECAUSE I WAS OVERWORKED. I THEN REGAINED MY HDG AND WITH LOTS OF HELP FROM ATC I GOT THE ACFT BACK TO BILLINGS SAFELY.

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.