|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1801 To 2400|
|Locale Reference||airport : isz.airport|
|Altitude||agl single value : 0|
|Operator||general aviation : personal|
|Make Model Name||PA-30 Twin Comanche|
|Operating Under FAR Part||Part 91|
|Flight Phase||landing : roll|
|Function||flight crew : single pilot|
|Qualification||pilot : multi engine|
pilot : commercial
pilot : instrument
|Experience||flight time last 90 days : 30|
flight time total : 1575
flight time type : 300
|Anomaly||aircraft equipment problem : critical|
ground encounters : gear up landing
|Independent Detector||other flight crewa|
|Resolutory Action||none taken : detected after the fact|
Flight Crew Human Performance
On extended right base, I lowered the landing gear handle. The yellow 'uplock' light went out, indicating that the gear was in transit. I extended approach flaps next, and was distraction by a dimming of the panel lights as a result of running the flap motor. I completed gumps check and saw a very dim green light. Put the rest of the flaps down. Tried to verify gear down with fish eye mirror on tip tank (this is part of my normal procedure), however, darkness prevented a visual inspection. The aircraft gently touched down on its belly. After stopping, the main gear was found to be extended about 2 inches (that's why the yellow went out) and the nose gear door had not started to open. The landing gear motor circuit breaker was popped. Contributing factor: in this model of the piper aircraft, the yellow and green landing gear indicator lights go to a dim setting when the panel light rheostat is turned on. The yellow light is still bright enough to be visible. However, when all panel lights are in the brightest setting, the green is so dim that it is hardly noticeable. When the green light is not lit, it is still showing some illumination from the panel back lighting. So, since I was expecting a very dim green light anyway, I thought the green was lit when it really only was getting bleed through lighting and causing a little glow. Solution: the rheostat for the panel lights should only cause the yellow up lock light to dim. That is the light that would be on throughout cruise. The green down lock light should not dim.
Original NASA ASRS Text
Title: PIPER PA30 PLT LANDED GEAR UP AFTER BELIEVING THAT THE GREEN GEAR POS LIGHT WAS ON AFTER MOVING THE GEAR HANDLE TO THE DOWN POS.
Narrative: ON EXTENDED R BASE, I LOWERED THE LNDG GEAR HANDLE. THE YELLOW 'UPLOCK' LIGHT WENT OUT, INDICATING THAT THE GEAR WAS IN TRANSIT. I EXTENDED APCH FLAPS NEXT, AND WAS DISTR BY A DIMMING OF THE PANEL LIGHTS AS A RESULT OF RUNNING THE FLAP MOTOR. I COMPLETED GUMPS CHK AND SAW A VERY DIM GREEN LIGHT. PUT THE REST OF THE FLAPS DOWN. TRIED TO VERIFY GEAR DOWN WITH FISH EYE MIRROR ON TIP TANK (THIS IS PART OF MY NORMAL PROC), HOWEVER, DARKNESS PREVENTED A VISUAL INSPECTION. THE ACFT GENTLY TOUCHED DOWN ON ITS BELLY. AFTER STOPPING, THE MAIN GEAR WAS FOUND TO BE EXTENDED ABOUT 2 INCHES (THAT'S WHY THE YELLOW WENT OUT) AND THE NOSE GEAR DOOR HAD NOT STARTED TO OPEN. THE LNDG GEAR MOTOR CIRCUIT BREAKER WAS POPPED. CONTRIBUTING FACTOR: IN THIS MODEL OF THE PIPER ACFT, THE YELLOW AND GREEN LNDG GEAR INDICATOR LIGHTS GO TO A DIM SETTING WHEN THE PANEL LIGHT RHEOSTAT IS TURNED ON. THE YELLOW LIGHT IS STILL BRIGHT ENOUGH TO BE VISIBLE. HOWEVER, WHEN ALL PANEL LIGHTS ARE IN THE BRIGHTEST SETTING, THE GREEN IS SO DIM THAT IT IS HARDLY NOTICEABLE. WHEN THE GREEN LIGHT IS NOT LIT, IT IS STILL SHOWING SOME ILLUMINATION FROM THE PANEL BACK LIGHTING. SO, SINCE I WAS EXPECTING A VERY DIM GREEN LIGHT ANYWAY, I THOUGHT THE GREEN WAS LIT WHEN IT REALLY ONLY WAS GETTING BLEED THROUGH LIGHTING AND CAUSING A LITTLE GLOW. SOLUTION: THE RHEOSTAT FOR THE PANEL LIGHTS SHOULD ONLY CAUSE THE YELLOW UP LOCK LIGHT TO DIM. THAT IS THE LIGHT THAT WOULD BE ON THROUGHOUT CRUISE. THE GREEN DOWN LOCK LIGHT SHOULD NOT DIM.
Data retrieved from NASA's ASRS site as of July 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.