Small aircraft has smoking engine, loss of power. Restores power returns to home field.

Attributes
ACN	247971
Time
Date	199307
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : isp
State Reference	NY
Altitude	msl bound lower : 2000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : isp tower : den
Operator	general aviation : instructional
Make Model Name	Small Aircraft, High Wing, 1 Eng, Fixed Gear
Flight Phase	descent : approach
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : private pilot : instrument
Experience	flight time last 90 days : 3 flight time total : 468 flight time type : 342
ASRS Report	247971
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

While on a practice localizer approach, the aircraft suffered a gradual loss of power. Level flight at 2000 ft and 70 KTS was maintained with the throttle fully advanced. At this time, the pilot of the aircraft behind me advised that my engine was trailing heavy black smoke. Instead of a missed approach, I requested and received clearance to land. In attempting various remedies, I pulled the mixture control back about 2 inches. The smoking stopped and full power was restored. After having climbed to almost 3000 ft, I was cleared to proceed directly to bayport airport, where the aircraft is based (located 2 1/2 mi southeast of isp). After numerous s-turns, a normal landing was made at bayport. Subsequent inspection revealed that a portion of the gasket from the carburetor heat door had been ingested into the carburetor. Perhaps a modified design of this item or an airworthiness directive regarding inspection or periodic replacement could prevent a recurrence.

Original NASA ASRS Text

Title: SMA HAS SMOKING ENG, LOSS OF PWR. RESTORES PWR RETURNS TO HOME FIELD.

Narrative: WHILE ON A PRACTICE LOC APCH, THE ACFT SUFFERED A GRADUAL LOSS OF PWR. LEVEL FLT AT 2000 FT AND 70 KTS WAS MAINTAINED WITH THE THROTTLE FULLY ADVANCED. AT THIS TIME, THE PLT OF THE ACFT BEHIND ME ADVISED THAT MY ENG WAS TRAILING HVY BLACK SMOKE. INSTEAD OF A MISSED APCH, I REQUESTED AND RECEIVED CLRNC TO LAND. IN ATTEMPTING VARIOUS REMEDIES, I PULLED THE MIXTURE CTL BACK ABOUT 2 INCHES. THE SMOKING STOPPED AND FULL PWR WAS RESTORED. AFTER HAVING CLBED TO ALMOST 3000 FT, I WAS CLRED TO PROCEED DIRECTLY TO BAYPORT ARPT, WHERE THE ACFT IS BASED (LOCATED 2 1/2 MI SE OF ISP). AFTER NUMEROUS S-TURNS, A NORMAL LNDG WAS MADE AT BAYPORT. SUBSEQUENT INSPECTION REVEALED THAT A PORTION OF THE GASKET FROM THE CARB HEAT DOOR HAD BEEN INGESTED INTO THE CARB. PERHAPS A MODIFIED DESIGN OF THIS ITEM OR AN AIRWORTHINESS DIRECTIVE REGARDING INSPECTION OR PERIODIC REPLACEMENT COULD PREVENT A RECURRENCE.

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.