C172 WITH STUCK TRIM ELEVATOR DECLARES EMER PRIOR TO LNDG ABI.

Narrative

ON THE RETURN TRIP 10 MI E OF ABI ARPT; ACFT WAS FLYING WBOUND HDG 270 DEGS AT 3000 FT MSL AT 70 KTS; 20 DEGS FLAPS. ACFT TRIM WAS SET FOR NOSE HIGH ATTITUDE; SLOW FLT. WHILE TRANSITIONING TO HIGH CRUISE SPD; 2600 RPM WAS SELECTED; AND NOSE DOWN TO LEVEL FLT COMMANDED AND TRIM TAB ADJUSTMENT WAS TAKING PLACE. THE ELEVATOR TRIM GOT STUCK AND THE ELEVATOR DID ALSO. ACFT STARTED ASCENDING WITH THE PWR SETTING (HIGH). UNABLE TO LOWER C172/U PITCH THE NEXT STEP WAS REDUCE PWR TO 2100 RPM. CLB STOPPED AT 3400 FT MSL. ABI APCH WAS CONTACTED ON 125.0; ASSISTANCE WAS OFFERED. THE PLAN WAS TO LAND AT 6F4. IF UNABLE TO LAND AT 6F4; ABI ARPT WOULD BE USED FOR AN EMER LNDG. REDUCING PWR FOR LNDG ON 20 DEGS FLAPS A SHALLOW DSCNT WAS ABLE. AILERON AND RUDDER NOT AFFECTED BY TRIM AND ELEVATOR MALFUNCTION. ATC STAYED WITH TILL SAFE LNDG AT 6F4. WX BRIEF; ACFT PREFLT DONE BY POH. FLT CTL CHKED OK PRIOR TO FLT. TRIM TAB GOT STUCK AFTER HAVING BEEN USED SEVERAL TIMES. NOTE: ACFT AND ELEVATOR CTL FELT HEAVIER THAN USUAL ON ROTATION (TKOF) AND DURING FLT. PULLING AND PUSHING THE YOKE AND ROTATING THE ELEVATOR TRIM TAB WAS OF LITTLE HELP. THE GOOD NEWS WAS WE LANDED WITHOUT CRASHING. ONE MORE DETAIL: ACFT WAS WITHIN WT AND BAL ENVELOPE -- 3 ADULTS; 1 CHILD; AND 3 HRS FUEL ON BOARD ON TKOF. GROSS WT 2200 LBS; 100.1 MOMENT.