Narrative:

Aircraft operating on ferry permit to finish our annual inspection with required pitot-static and transponder check as noted in 'periodic inspection guide;' manufacturer's maintenance manual. ZZZZ is the closet maintenance facility to perform this task. On downwind; landing gear failed to extend. Warning horn sounded on throttle reduction; unsafe gear indication in cockpit. Performed go around to troubleshoot. Manual gear extension gave green down and locked indication as did the mechanical indication in cockpit. No horn on throttle reduction. Right gear appears to have not extended and aircraft settled on right flap on rollout. Emergency checklist was followed during this event. All indications showed successful emergency gear extension. Supplemental information from acn 797619: I took off in my beech travel air with my copilot/aircraft mechanic on board. The WX was gorgeous; and a VFR flight plan was filed and activated. The flight was uneventful until we were cleared to land in ZZZZ. The aircraft had been sitting idle for almost 10 months during engine overhauls and an annual inspection. During our approach; normal procedures were followed including the placing of the landing gear lever in the down position. When that was done; no green light came on; and; as power was reduced for landing; the gear warning horn was activated. We notified the tower that we were going around. The tower asked why. I explained that we had a landing gear problem. ATC then vectored us away from the airport into a VFR holding pattern several mi away allowing us to troubleshoot the problem. With difficulty; we were finally able to manually deploy the landing gear by hand cranking in accordance with the emergency procedure outlined in the poh and the emergency checklist until we got a green landing gear light; and the mechanical gear extension indicator also indicated that the gear was down and locked. Additionally; I could see in the small mirror on the inboard side of the left engine nacelle that the nose gear was down and locked. We then told ATC that we had solved the problem; and that we were ready to return for landing. ATC then vectored us back to the airport; and the tower cleared us to land. I touched down on runway in one of my smoothest and best lndgs ever; I had a green landing light; a mechanical 'gear down and locked' indication; and no gear warning horn. The aircraft then proceeded straight ahead down the runway on a very normal landing rollout. Then after about 30 seconds; the right wing suddenly dropped; and the aircraft veered to the right with the horrible sound of the scraping metal. I immediately pulled back on mixtures; throttles; and propeller controls; and applied maximum braking. The aircraft came to a stop on the right side of the runway. There was no fire; and no one was injured. In post-incident research; I learned that one should not stop cranking the gear down as soon as one sees a green light and mechanical indicator indicating that the gear is down and locked; and that one should continue cranking (perhaps one more full or half turn) until the crank can turn no more; otherwise a gear collapse on rollout could happen like it happened to me. Callback conversation with reporter revealed the following information: reporter stated the beech travel air 95 landing gear is extended and retracted by an electric motor driven gear box with microswitches. During earlier maintenance; the aircraft had performed four complete electric gear retract and extend cycles while on jacks without any problems. This beech 95 has only one green light to indicate all three gears are down and locked. The control arms for the landing gear push-pull tubes activate each gear microswitch. Reporter stated they found out later the rt gear uplock had not released; due to a broken uplock release cable. This prevented the gear from extending; electrically or mechanically. They also found out when manually extending the gear for fifty turns with the hand crank; which is located on the aft side of the center wing section; enough force can be exerted to bend the landing gear push-pull tubes and allow the control arms where the microswitches are located to give a false indication that all gearare down and locked. This included a green light indicating all gear down and locked; a mechanical pointer indicating 'gear down and locked' and no gear horn activated during throttle reduction.

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Original NASA ASRS Text

Title: A MECHANIC AND PILOT REPORT ON LANDING A BEECH TRAVEL AIR 95 WITH THE RT MAIN GEAR NOT DOWN EVEN THOUGH THEY HAD A GREEN LANDING LIGHT; A MECHANICAL GEAR DOWN AND LOCKED INDICATION AND NO GEAR WARNING HORN DURING THROTTLE REDUCTION.

Narrative: ACFT OPERATING ON FERRY PERMIT TO FINISH OUR ANNUAL INSPECTION WITH REQUIRED PITOT-STATIC AND XPONDER CHK AS NOTED IN 'PERIODIC INSPECTION GUIDE;' MANUFACTURER'S MAINT MANUAL. ZZZZ IS THE CLOSET MAINT FACILITY TO PERFORM THIS TASK. ON DOWNWIND; LNDG GEAR FAILED TO EXTEND. WARNING HORN SOUNDED ON THROTTLE REDUCTION; UNSAFE GEAR INDICATION IN COCKPIT. PERFORMED GAR TO TROUBLESHOOT. MANUAL GEAR EXTENSION GAVE GREEN DOWN AND LOCKED INDICATION AS DID THE MECHANICAL INDICATION IN COCKPIT. NO HORN ON THROTTLE REDUCTION. R GEAR APPEARS TO HAVE NOT EXTENDED AND ACFT SETTLED ON R FLAP ON ROLLOUT. EMER CHKLIST WAS FOLLOWED DURING THIS EVENT. ALL INDICATIONS SHOWED SUCCESSFUL EMER GEAR EXTENSION. SUPPLEMENTAL INFO FROM ACN 797619: I TOOK OFF IN MY BEECH TRAVEL AIR WITH MY COPLT/ACFT MECH ON BOARD. THE WX WAS GORGEOUS; AND A VFR FLT PLAN WAS FILED AND ACTIVATED. THE FLT WAS UNEVENTFUL UNTIL WE WERE CLRED TO LAND IN ZZZZ. THE ACFT HAD BEEN SITTING IDLE FOR ALMOST 10 MONTHS DURING ENG OVERHAULS AND AN ANNUAL INSPECTION. DURING OUR APCH; NORMAL PROCS WERE FOLLOWED INCLUDING THE PLACING OF THE LNDG GEAR LEVER IN THE DOWN POS. WHEN THAT WAS DONE; NO GREEN LIGHT CAME ON; AND; AS PWR WAS REDUCED FOR LNDG; THE GEAR WARNING HORN WAS ACTIVATED. WE NOTIFIED THE TWR THAT WE WERE GOING AROUND. THE TWR ASKED WHY. I EXPLAINED THAT WE HAD A LNDG GEAR PROB. ATC THEN VECTORED US AWAY FROM THE ARPT INTO A VFR HOLDING PATTERN SEVERAL MI AWAY ALLOWING US TO TROUBLESHOOT THE PROB. WITH DIFFICULTY; WE WERE FINALLY ABLE TO MANUALLY DEPLOY THE LNDG GEAR BY HAND CRANKING IN ACCORDANCE WITH THE EMER PROC OUTLINED IN THE POH AND THE EMER CHKLIST UNTIL WE GOT A GREEN LNDG GEAR LIGHT; AND THE MECHANICAL GEAR EXTENSION INDICATOR ALSO INDICATED THAT THE GEAR WAS DOWN AND LOCKED. ADDITIONALLY; I COULD SEE IN THE SMALL MIRROR ON THE INBOARD SIDE OF THE L ENG NACELLE THAT THE NOSE GEAR WAS DOWN AND LOCKED. WE THEN TOLD ATC THAT WE HAD SOLVED THE PROB; AND THAT WE WERE READY TO RETURN FOR LNDG. ATC THEN VECTORED US BACK TO THE ARPT; AND THE TWR CLRED US TO LAND. I TOUCHED DOWN ON RWY IN ONE OF MY SMOOTHEST AND BEST LNDGS EVER; I HAD A GREEN LNDG LIGHT; A MECHANICAL 'GEAR DOWN AND LOCKED' INDICATION; AND NO GEAR WARNING HORN. THE ACFT THEN PROCEEDED STRAIGHT AHEAD DOWN THE RWY ON A VERY NORMAL LNDG ROLLOUT. THEN AFTER ABOUT 30 SECONDS; THE R WING SUDDENLY DROPPED; AND THE ACFT VEERED TO THE R WITH THE HORRIBLE SOUND OF THE SCRAPING METAL. I IMMEDIATELY PULLED BACK ON MIXTURES; THROTTLES; AND PROP CTLS; AND APPLIED MAX BRAKING. THE ACFT CAME TO A STOP ON THE R SIDE OF THE RWY. THERE WAS NO FIRE; AND NO ONE WAS INJURED. IN POST-INCIDENT RESEARCH; I LEARNED THAT ONE SHOULD NOT STOP CRANKING THE GEAR DOWN AS SOON AS ONE SEES A GREEN LIGHT AND MECHANICAL INDICATOR INDICATING THAT THE GEAR IS DOWN AND LOCKED; AND THAT ONE SHOULD CONTINUE CRANKING (PERHAPS ONE MORE FULL OR HALF TURN) UNTIL THE CRANK CAN TURN NO MORE; OTHERWISE A GEAR COLLAPSE ON ROLLOUT COULD HAPPEN LIKE IT HAPPENED TO ME. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: REPORTER STATED THE BEECH TRAVEL AIR 95 LANDING GEAR IS EXTENDED AND RETRACTED BY AN ELECTRIC MOTOR DRIVEN GEAR BOX WITH MICROSWITCHES. DURING EARLIER MAINT; THE ACFT HAD PERFORMED FOUR COMPLETE ELECTRIC GEAR RETRACT AND EXTEND CYCLES WHILE ON JACKS WITHOUT ANY PROBLEMS. THIS BEECH 95 HAS ONLY ONE GREEN LIGHT TO INDICATE ALL THREE GEARS ARE DOWN AND LOCKED. THE CONTROL ARMS FOR THE LANDING GEAR PUSH-PULL TUBES ACTIVATE EACH GEAR MICROSWITCH. REPORTER STATED THEY FOUND OUT LATER THE RT GEAR UPLOCK HAD NOT RELEASED; DUE TO A BROKEN UPLOCK RELEASE CABLE. THIS PREVENTED THE GEAR FROM EXTENDING; ELECTRICALLY OR MECHANICALLY. THEY ALSO FOUND OUT WHEN MANUALLY EXTENDING THE GEAR FOR FIFTY TURNS WITH THE HAND CRANK; WHICH IS LOCATED ON THE AFT SIDE OF THE CENTER WING SECTION; ENOUGH FORCE CAN BE EXERTED TO BEND THE LANDING GEAR PUSH-PULL TUBES AND ALLOW THE CONTROL ARMS WHERE THE MICROSWITCHES ARE LOCATED TO GIVE A FALSE INDICATION THAT ALL GEARARE DOWN AND LOCKED. THIS INCLUDED A GREEN LIGHT INDICATING ALL GEAR DOWN AND LOCKED; A MECHANICAL POINTER INDICATING 'GEAR DOWN AND LOCKED' AND NO GEAR HORN ACTIVATED DURING THROTTLE REDUCTION.

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.