Narrative:

On first leg of 2-LEG trip; throttle felt slightly loose; like needed tightening. Made note to check when we got home. Couldn't find anything wrong during preflight or run-up for second leg. Uneventful trip home at 6000 ft. Left throttle wide open as usual. Began descent. WX clear and 10; winds calm. Advised airport in sight about 10 NM out. Approach cleared me for visual runway 14L and handed me off to tower. Near airport; tried to slow; found throttle completely disconnected; could move lever forward and aft; but no change in manifold pressure. Since other controls working properly; decided to land using propeller; gear and flaps to control speed. Tower cleared me to land on runway 14L. Entered left base. Airspeed on final about 110 KTS (versus 90 KT target). Attempted to land despite higher speed; but aborted landing after bouncing twice. Advised tower going around; throttle problem. Told make right traffic; plan for runway 14R. Acknowledged change in runways; continued climb out; began turn and selected gear up. Gear lights stayed green; red 'in transit' light never came on; rate of climb lower than normal. On our BE36; alarm sounds if throttle retarded while gear up. Wondered if reverse logic prevented gear retraction. Told tower I wanted to depart pattern and troubleshoot before trying another landing. Tower said squawk 1200 and handed me back to approach. Told to maintain VFR at or below 3500 ft; asked for souls and fuel on board; and approved frequency change so I could contact local FBO/beechcraft maintenance shop. Discussed situation with maintenance manager via relay through FBO line manager. Decided nothing we could do about throttle airborne; ok to land using remaining controls; after verifying gear was down/locked. Reviewed poh; pulled gear motor breaker; removed handle cover; deployed handle; and turned about 25 turns in wrong direction. Green lights went off and red light came on. Turned handle about 25 turns in correct direction; red light went out and green lights came back on. Maintenance manager agreed gear must be down. Switched back to approach and advised ready to land but engine might quit once on ground. Declined offer to have equipment standing by. Approach gave heading back to airport; cleared visual runway 14R and handed me off to tower. Tower cleared me to land and advised other traffic they might have to switch runways. Set up for extended final; slowed to about 80 KTS; had passenger crack door open; and set down as gently as possible. Landing gear held. Slowed to taxi speed; exited at taxiway to FBO's ramp. Thanked tower for help; taxied to ramp and shut down. Next work day; mechanic found throttle control arm loose on throttle body. Torqued self-locking throttle control arm nut; found it could turn 1/3 of full turn. Replaced nut and torqued. Mechanic believes nut last tightened when engine replaced about 2 yrs/270 hours prior to incident. Mechanic checked landing gear. Couldn't replicate problem raising gear. Suspects bounces might have temporarily jarred one of squat switches. Lessons learned: 1) don't postpone maintenance involving key system or controls. 2) don't hesitate to advise ATC if a problem develops. 3) if required to go around and having problems with other system or controls; consider leaving gear down to minimize variables. 4) plan extended final if uncertain about speed control. 5) learn more about aircraft system. 6) double-check turn direction before using manual gear extension procedure. 7) find better way to communicate with maintenance while airborne.

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Original NASA ASRS Text

Title: A BE36 PILOT EXPERIENCED LOSS OF THROTTLE CONTROL WHEN A NUT ON THE THROTTLE BODY CAME LOOSE. HE MADE A SUCCESSFUL LANDING USING PROPELLER PITCH; GEAR; AND FLAPS TO CONTROL SPEED.

Narrative: ON FIRST LEG OF 2-LEG TRIP; THROTTLE FELT SLIGHTLY LOOSE; LIKE NEEDED TIGHTENING. MADE NOTE TO CHK WHEN WE GOT HOME. COULDN'T FIND ANYTHING WRONG DURING PREFLT OR RUN-UP FOR SECOND LEG. UNEVENTFUL TRIP HOME AT 6000 FT. L THROTTLE WIDE OPEN AS USUAL. BEGAN DSCNT. WX CLR AND 10; WINDS CALM. ADVISED ARPT IN SIGHT ABOUT 10 NM OUT. APCH CLRED ME FOR VISUAL RWY 14L AND HANDED ME OFF TO TWR. NEAR ARPT; TRIED TO SLOW; FOUND THROTTLE COMPLETELY DISCONNECTED; COULD MOVE LEVER FORWARD AND AFT; BUT NO CHANGE IN MANIFOLD PRESSURE. SINCE OTHER CTLS WORKING PROPERLY; DECIDED TO LAND USING PROP; GEAR AND FLAPS TO CTL SPD. TWR CLRED ME TO LAND ON RWY 14L. ENTERED L BASE. AIRSPD ON FINAL ABOUT 110 KTS (VERSUS 90 KT TARGET). ATTEMPTED TO LAND DESPITE HIGHER SPD; BUT ABORTED LNDG AFTER BOUNCING TWICE. ADVISED TWR GOING AROUND; THROTTLE PROB. TOLD MAKE R TFC; PLAN FOR RWY 14R. ACKNOWLEDGED CHANGE IN RWYS; CONTINUED CLBOUT; BEGAN TURN AND SELECTED GEAR UP. GEAR LIGHTS STAYED GREEN; RED 'IN TRANSIT' LIGHT NEVER CAME ON; RATE OF CLB LOWER THAN NORMAL. ON OUR BE36; ALARM SOUNDS IF THROTTLE RETARDED WHILE GEAR UP. WONDERED IF REVERSE LOGIC PREVENTED GEAR RETRACTION. TOLD TWR I WANTED TO DEPART PATTERN AND TROUBLESHOOT BEFORE TRYING ANOTHER LNDG. TWR SAID SQUAWK 1200 AND HANDED ME BACK TO APCH. TOLD TO MAINTAIN VFR AT OR BELOW 3500 FT; ASKED FOR SOULS AND FUEL ON BOARD; AND APPROVED FREQ CHANGE SO I COULD CONTACT LCL FBO/BEECHCRAFT MAINT SHOP. DISCUSSED SITUATION WITH MAINT MGR VIA RELAY THROUGH FBO LINE MGR. DECIDED NOTHING WE COULD DO ABOUT THROTTLE AIRBORNE; OK TO LAND USING REMAINING CTLS; AFTER VERIFYING GEAR WAS DOWN/LOCKED. REVIEWED POH; PULLED GEAR MOTOR BREAKER; REMOVED HANDLE COVER; DEPLOYED HANDLE; AND TURNED ABOUT 25 TURNS IN WRONG DIRECTION. GREEN LIGHTS WENT OFF AND RED LIGHT CAME ON. TURNED HANDLE ABOUT 25 TURNS IN CORRECT DIRECTION; RED LIGHT WENT OUT AND GREEN LIGHTS CAME BACK ON. MAINT MGR AGREED GEAR MUST BE DOWN. SWITCHED BACK TO APCH AND ADVISED READY TO LAND BUT ENG MIGHT QUIT ONCE ON GND. DECLINED OFFER TO HAVE EQUIP STANDING BY. APCH GAVE HDG BACK TO ARPT; CLRED VISUAL RWY 14R AND HANDED ME OFF TO TWR. TWR CLRED ME TO LAND AND ADVISED OTHER TFC THEY MIGHT HAVE TO SWITCH RWYS. SET UP FOR EXTENDED FINAL; SLOWED TO ABOUT 80 KTS; HAD PAX CRACK DOOR OPEN; AND SET DOWN AS GENTLY AS POSSIBLE. LNDG GEAR HELD. SLOWED TO TAXI SPD; EXITED AT TXWY TO FBO'S RAMP. THANKED TWR FOR HELP; TAXIED TO RAMP AND SHUT DOWN. NEXT WORK DAY; MECH FOUND THROTTLE CTL ARM LOOSE ON THROTTLE BODY. TORQUED SELF-LOCKING THROTTLE CTL ARM NUT; FOUND IT COULD TURN 1/3 OF FULL TURN. REPLACED NUT AND TORQUED. MECH BELIEVES NUT LAST TIGHTENED WHEN ENG REPLACED ABOUT 2 YRS/270 HRS PRIOR TO INCIDENT. MECH CHKED LNDG GEAR. COULDN'T REPLICATE PROB RAISING GEAR. SUSPECTS BOUNCES MIGHT HAVE TEMPORARILY JARRED ONE OF SQUAT SWITCHES. LESSONS LEARNED: 1) DON'T POSTPONE MAINT INVOLVING KEY SYS OR CTLS. 2) DON'T HESITATE TO ADVISE ATC IF A PROB DEVELOPS. 3) IF REQUIRED TO GO AROUND AND HAVING PROBS WITH OTHER SYS OR CTLS; CONSIDER LEAVING GEAR DOWN TO MINIMIZE VARIABLES. 4) PLAN EXTENDED FINAL IF UNCERTAIN ABOUT SPD CTL. 5) LEARN MORE ABOUT ACFT SYS. 6) DOUBLE-CHK TURN DIRECTION BEFORE USING MANUAL GEAR EXTENSION PROC. 7) FIND BETTER WAY TO COMMUNICATE WITH MAINT WHILE AIRBORNE.

Data retrieved from NASA's ASRS site as of May 2009 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.