|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0001 To 0600|
|Locale Reference||airport : unv|
|Altitude||agl bound lower : 0|
agl bound upper : 1500
|Controlling Facilities||tracon : las|
|Operator||common carrier : air carrier|
|Make Model Name||Small Transport, Low Wing, 2 Turboprop Eng|
|Flight Phase||climbout : initial|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Experience||flight time last 90 days : 120|
flight time total : 17000
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Qualification||pilot : commercial|
pilot : instrument
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||aircraft equipment other aircraft equipment : unspecified|
other flight crewa
|Resolutory Action||none taken : unable|
|Air Traffic Incident||other|
On takeoff gear was raised. We had an unsafe gear up indication (flashing red on handle). Returned to the airport, attempted normal gear down after checking all circuit breaker's and flight manual procedures. We had nose wheel safe, right gear safe, left gear, no green light and unsafe flashing gear handle. We had called and had all the airport personnel available, head mechanic and ass't. They recommended raising the gear and pumping it down. We had the same situation. Since the left gear was locked half down, everyone decided it would be better to attempt a gear down landing. On landing, the left gear collapsed at 40+ KTS. Supplemental information from acn 81242: no injuries. Left propeller and wing damaged. Callback conversation with reporter revealed the following: after the landing the pilot who is also an a&P mechanic stayed around while mechanics inspected aircraft. Upon opening cover plate over top of torque screw that operates the landing gear they found that a stainless steel clamp on an air duct in the same area had worked around until it was against the torque screw and then every time the landing was activated, it had acted like a cutting lathe on the torque screw until it had weakened it enough so that when the 2400 RPM electrical motor hit the jack screw, it sheared. Reporter also reported FAA investigated the occurrence and classified it an incident. The FAA also put out a letter to all operators of this model aircraft to inspect this stainless steel clamp for correct size and clearance.
Original NASA ASRS Text
Title: ACR SMT UNABLE RETRACT LEFT MAIN GEAR AFTER TKOF. ALSO UNABLE EXTEND IT FULLY FOR LNDG AND ON LNDG ROLLOUT IT COLLAPSED CAUSING WING AND PROPELLER DAMAGE.
Narrative: ON TKOF GEAR WAS RAISED. WE HAD AN UNSAFE GEAR UP INDICATION (FLASHING RED ON HANDLE). RETURNED TO THE ARPT, ATTEMPTED NORMAL GEAR DOWN AFTER CHKING ALL CB'S AND FLT MANUAL PROCS. WE HAD NOSE WHEEL SAFE, RIGHT GEAR SAFE, LEFT GEAR, NO GREEN LIGHT AND UNSAFE FLASHING GEAR HANDLE. WE HAD CALLED AND HAD ALL THE ARPT PERSONNEL AVAILABLE, HEAD MECHANIC AND ASS'T. THEY RECOMMENDED RAISING THE GEAR AND PUMPING IT DOWN. WE HAD THE SAME SITUATION. SINCE THE LEFT GEAR WAS LOCKED HALF DOWN, EVERYONE DECIDED IT WOULD BE BETTER TO ATTEMPT A GEAR DOWN LNDG. ON LNDG, THE LEFT GEAR COLLAPSED AT 40+ KTS. SUPPLEMENTAL INFORMATION FROM ACN 81242: NO INJURIES. LEFT PROP AND WING DAMAGED. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: AFTER THE LNDG THE PLT WHO IS ALSO AN A&P MECHANIC STAYED AROUND WHILE MECHANICS INSPECTED ACFT. UPON OPENING COVER PLATE OVER TOP OF TORQUE SCREW THAT OPERATES THE LNDG GEAR THEY FOUND THAT A STAINLESS STEEL CLAMP ON AN AIR DUCT IN THE SAME AREA HAD WORKED AROUND UNTIL IT WAS AGAINST THE TORQUE SCREW AND THEN EVERY TIME THE LNDG WAS ACTIVATED, IT HAD ACTED LIKE A CUTTING LATHE ON THE TORQUE SCREW UNTIL IT HAD WEAKENED IT ENOUGH SO THAT WHEN THE 2400 RPM ELECTRICAL MOTOR HIT THE JACK SCREW, IT SHEARED. RPTR ALSO RPTED FAA INVESTIGATED THE OCCURRENCE AND CLASSIFIED IT AN INCIDENT. THE FAA ALSO PUT OUT A LETTER TO ALL OPERATORS OF THIS MODEL ACFT TO INSPECT THIS STAINLESS STEEL CLAMP FOR CORRECT SIZE AND CLRNC.
Data retrieved from NASA's ASRS site as of August 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.