Narrative:

I was checking out a flying club member in an small aircraft. The club member stated he had previously flown about 30 hours in an small aircraft. The chkout was an insurance requirement on the club's policy. It has to be conducted by a club member familiar with the aircraft or a CFI. I am a cfii and club member. I had considerable experience in the aircraft, including obtaining CFI certification in an small aircraft. Upon retracting the gear after takeoff the 3 green gear down indicators went out, but the landing gear unsafe indicator remained lit. We accelerated slightly to see if the automatic extension mechanism was preventing retraction. At low airspds it will not let the gear come up. The indicator remained lit. Next we activated the gear up override. This had no effect on the light. We decided T extend the gear and land. We selected gear down. The landing gear unsafe light remained lit. The 3 green gear position lights remained unlit. We checked that they were not just dimmed by the panel light on-off switch--they were definitely not lit. We referred to the emergency gear extension checklist and followed it, performing all items except replacing or swapping the light bulbs. We believed that swapping the bulbs would be useless since none of the gear position lights were lit. We felt that there was additional drag being created by the gear and it might be down. We circled on the downwind while we did the checks under clearance from the tower. We asked the tower for a low approach and for tower confirmation that the gear was in the down position. We did this and tower stated that the gear was down. Back on the downwind I finally decided to try checking the light bulbs even though I doubted very much that it could help. When I removed the nose wheel indicator bulb, the 2 main wheel lights came on.when we put one of the main wheel lights in the nose wheel position, it lit up, but only if positioned in a certain way. Having obtained some indication on all 3 position lights that the circuit was closed and the gear was down, we advised the tower that we thought the problem was corrected and had an uneventful landing. No emergency was ever declared, but the tower, on its own initiative, called out the emergency trucks in the event that the gear collapsed. To be on the safe side, we also prepared for a possible gear collapse prior to landing. The most significant thing I want to report is that checking the landing gear position lights, by pulling them out, solved the apparent short in the system, although my inclination (and I suspect that of most pilots) would be to skip this when none of the indicators will light. The aircraft was put in maintenance.

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Original NASA ASRS Text

Title: GEAR LIGHTS MALFUNCTION INDICATING GEAR IN UNSAFE POSITION. TRIED PRESCRIBED PROCS, DID FLY BY TWR TO CONFIRM GEAR DOWN, LANDED.

Narrative: I WAS CHKING OUT A FLYING CLUB MEMBER IN AN SMA. THE CLUB MEMBER STATED HE HAD PREVIOUSLY FLOWN ABOUT 30 HRS IN AN SMA. THE CHKOUT WAS AN INSURANCE REQUIREMENT ON THE CLUB'S POLICY. IT HAS TO BE CONDUCTED BY A CLUB MEMBER FAMILIAR WITH THE ACFT OR A CFI. I AM A CFII AND CLUB MEMBER. I HAD CONSIDERABLE EXPERIENCE IN THE ACFT, INCLUDING OBTAINING CFI CERTIFICATION IN AN SMA. UPON RETRACTING THE GEAR AFTER TKOF THE 3 GREEN GEAR DOWN INDICATORS WENT OUT, BUT THE LNDG GEAR UNSAFE INDICATOR REMAINED LIT. WE ACCELERATED SLIGHTLY TO SEE IF THE AUTO EXTENSION MECHANISM WAS PREVENTING RETRACTION. AT LOW AIRSPDS IT WILL NOT LET THE GEAR COME UP. THE INDICATOR REMAINED LIT. NEXT WE ACTIVATED THE GEAR UP OVERRIDE. THIS HAD NO EFFECT ON THE LIGHT. WE DECIDED T EXTEND THE GEAR AND LAND. WE SELECTED GEAR DOWN. THE LNDG GEAR UNSAFE LIGHT REMAINED LIT. THE 3 GREEN GEAR POS LIGHTS REMAINED UNLIT. WE CHKED THAT THEY WERE NOT JUST DIMMED BY THE PANEL LIGHT ON-OFF SWITCH--THEY WERE DEFINITELY NOT LIT. WE REFERRED TO THE EMER GEAR EXTENSION CHKLIST AND FOLLOWED IT, PERFORMING ALL ITEMS EXCEPT REPLACING OR SWAPPING THE LIGHT BULBS. WE BELIEVED THAT SWAPPING THE BULBS WOULD BE USELESS SINCE NONE OF THE GEAR POS LIGHTS WERE LIT. WE FELT THAT THERE WAS ADDITIONAL DRAG BEING CREATED BY THE GEAR AND IT MIGHT BE DOWN. WE CIRCLED ON THE DOWNWIND WHILE WE DID THE CHKS UNDER CLRNC FROM THE TWR. WE ASKED THE TWR FOR A LOW APCH AND FOR TWR CONFIRMATION THAT THE GEAR WAS IN THE DOWN POS. WE DID THIS AND TWR STATED THAT THE GEAR WAS DOWN. BACK ON THE DOWNWIND I FINALLY DECIDED TO TRY CHKING THE LIGHT BULBS EVEN THOUGH I DOUBTED VERY MUCH THAT IT COULD HELP. WHEN I REMOVED THE NOSE WHEEL INDICATOR BULB, THE 2 MAIN WHEEL LIGHTS CAME ON.WHEN WE PUT ONE OF THE MAIN WHEEL LIGHTS IN THE NOSE WHEEL POSITION, IT LIT UP, BUT ONLY IF POSITIONED IN A CERTAIN WAY. HAVING OBTAINED SOME INDICATION ON ALL 3 POS LIGHTS THAT THE CIRCUIT WAS CLOSED AND THE GEAR WAS DOWN, WE ADVISED THE TWR THAT WE THOUGHT THE PROB WAS CORRECTED AND HAD AN UNEVENTFUL LNDG. NO EMER WAS EVER DECLARED, BUT THE TWR, ON ITS OWN INITIATIVE, CALLED OUT THE EMER TRUCKS IN THE EVENT THAT THE GEAR COLLAPSED. TO BE ON THE SAFE SIDE, WE ALSO PREPARED FOR A POSSIBLE GEAR COLLAPSE PRIOR TO LNDG. THE MOST SIGNIFICANT THING I WANT TO RPT IS THAT CHKING THE LNDG GEAR POS LIGHTS, BY PULLING THEM OUT, SOLVED THE APPARENT SHORT IN THE SYS, ALTHOUGH MY INCLINATION (AND I SUSPECT THAT OF MOST PLTS) WOULD BE TO SKIP THIS WHEN NONE OF THE INDICATORS WILL LIGHT. THE ACFT WAS PUT IN MAINT.

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.