|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||airport : bak|
|Altitude||agl bound lower : 0|
agl bound upper : 0
|Controlling Facilities||tower : cdw|
|Operator||general aviation : instructional|
|Make Model Name||Small Transport, Low Wing, 2 Recip Eng|
|Flight Phase||landing other|
|Function||flight crew : single pilot|
|Qualification||pilot : cfi|
pilot : instrument
pilot : commercial
|Experience||flight time last 90 days : 84|
flight time total : 2057
flight time type : 198
|Function||controller : local|
|Qualification||controller : non radar|
|Anomaly||aircraft equipment problem : critical|
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : declared emergency|
none taken : unable
|Consequence||faa : investigated|
At approximately 4 mi north of bak I extended approach flaps and noted a flap asymmetry (the left flap did not extend as much as the right flap) causing a rolling moment to the left. At 3 mi north of the approach end of runway 5 I extended the aircraft's landing gear and checked for 3 green lights (down and locked). I then completed the before-landing checklist, contacted the tower, called a left base and was cleared to land. I turned onto final approach when landing was assured, extended full flaps and checked the landing indicator lights again. Note: flap asymmetry increased as full flaps were selected. I then made a normal landing and after the nose gear touched the runway I relaxed back pressure on the control yoke. When I did this I noticed that the nose of the aircraft appeared to lower further than normal but did not think this was out of the ordinary at the time. I then selected flaps up to relieve the flap asymmetry and increase deceleration. Approximately 2-3 seconds later I felt the left wing of the aircraft drop. I first thought that the gear strut went flat then immediately realized that the gear was collapsing. It should be noted that no gear warning was heard until this point. I immediately checked the gear selector knob and saw that it was in the down position. The right gear then collapsed and both propellers struck the pavement. The aircraft then slid on its belly for approximately 200' before it finally came to rest. After the aircraft stopped I secured the aircraft's fuel and electrical systems and exited through the aircraft's main door where I was met by the airport manager at the scene. Although the cause of the incident has not yet been determined, I strongly suspect an electrical or mechanical malfunction. There are 3 items which support his claim. First, the gear was down and with a locked indication before T/D as evidenced by the gear indicator lights, tire skid marks, and eyewitnesses. Second, the flaps were correctly selected up (and not the gear) as evidence by no visible signs of damage to either flap. Third, this aircraft has had a history of landing gear malfunction.
Original NASA ASRS Text
Title: LNDG GEAR COLLAPSED DURING LNDG ROLL.
Narrative: AT APPROX 4 MI N OF BAK I EXTENDED APCH FLAPS AND NOTED A FLAP ASYMMETRY (THE LEFT FLAP DID NOT EXTEND AS MUCH AS THE RIGHT FLAP) CAUSING A ROLLING MOMENT TO THE LEFT. AT 3 MI N OF THE APCH END OF RWY 5 I EXTENDED THE ACFT'S LNDG GEAR AND CHKED FOR 3 GREEN LIGHTS (DOWN AND LOCKED). I THEN COMPLETED THE BEFORE-LNDG CHKLIST, CONTACTED THE TWR, CALLED A LEFT BASE AND WAS CLRED TO LAND. I TURNED ONTO FINAL APCH WHEN LNDG WAS ASSURED, EXTENDED FULL FLAPS AND CHKED THE LNDG INDICATOR LIGHTS AGAIN. NOTE: FLAP ASYMMETRY INCREASED AS FULL FLAPS WERE SELECTED. I THEN MADE A NORMAL LNDG AND AFTER THE NOSE GEAR TOUCHED THE RWY I RELAXED BACK PRESSURE ON THE CONTROL YOKE. WHEN I DID THIS I NOTICED THAT THE NOSE OF THE ACFT APPEARED TO LOWER FURTHER THAN NORMAL BUT DID NOT THINK THIS WAS OUT OF THE ORDINARY AT THE TIME. I THEN SELECTED FLAPS UP TO RELIEVE THE FLAP ASYMMETRY AND INCREASE DECELERATION. APPROX 2-3 SECS LATER I FELT THE LEFT WING OF THE ACFT DROP. I FIRST THOUGHT THAT THE GEAR STRUT WENT FLAT THEN IMMEDIATELY REALIZED THAT THE GEAR WAS COLLAPSING. IT SHOULD BE NOTED THAT NO GEAR WARNING WAS HEARD UNTIL THIS POINT. I IMMEDIATELY CHKED THE GEAR SELECTOR KNOB AND SAW THAT IT WAS IN THE DOWN POS. THE RIGHT GEAR THEN COLLAPSED AND BOTH PROPS STRUCK THE PAVEMENT. THE ACFT THEN SLID ON ITS BELLY FOR APPROX 200' BEFORE IT FINALLY CAME TO REST. AFTER THE ACFT STOPPED I SECURED THE ACFT'S FUEL AND ELECTRICAL SYSTEMS AND EXITED THROUGH THE ACFT'S MAIN DOOR WHERE I WAS MET BY THE ARPT MGR AT THE SCENE. ALTHOUGH THE CAUSE OF THE INCIDENT HAS NOT YET BEEN DETERMINED, I STRONGLY SUSPECT AN ELECTRICAL OR MECHANICAL MALFUNCTION. THERE ARE 3 ITEMS WHICH SUPPORT HIS CLAIM. FIRST, THE GEAR WAS DOWN AND WITH A LOCKED INDICATION BEFORE T/D AS EVIDENCED BY THE GEAR INDICATOR LIGHTS, TIRE SKID MARKS, AND EYEWITNESSES. SECOND, THE FLAPS WERE CORRECTLY SELECTED UP (AND NOT THE GEAR) AS EVIDENCE BY NO VISIBLE SIGNS OF DAMAGE TO EITHER FLAP. THIRD, THIS ACFT HAS HAD A HISTORY OF LNDG GEAR MALFUNCTION.
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.