Narrative:

As I approached my destination; I selected approach flaps and moved the gear selector switch to the down position to lower the gear. I noticed that I had a green indication on the nose gear position light; and the left main gear position light; but no light on the right main gear. I pushed the bulb lens housing (testing the bulb) and I received a green light; so the bulb was good. I then removed the lens cover and did a test again just to make sure; and I received a good indication. I slowed the aircraft to the gear retraction speed and moved the gear selector switch to the up position; retracting the gear. With the gear in the up position I now had a red 'not locked' indicator light indicating the gear was not locked in the up position. I placed the gear selector switch in the down position for the second time to see if the gear would indicate 3 green down and locked position lights. I received the same results as before with the addition of the red 'not locked' indicator illuminated. I repeated this procedure one more time with the same results. I followed the checklist and performed the emergency gear extension procedure. I completed the procedure; felt pressure on the pump; but my primary indicators were still showing the red 'not locked' indicator illuminated and a green light on the nose gear and the left main gear; but no green light on the right main gear. At this point I am concerned and have no confidence the right main gear is down and locked. I am also concerned for the safety of the six passengers I have on board the aircraft. I wanted to fly to an airport that I knew had emergency equipment; so I called approach; declared an emergency and requested to return to our departure airport and to fly by the tower to have the gear visually inspected. The tower indicated all three landing gears appeared to be down. I was vectored behind another aircraft on a 8 mile final and landed safely without incident. I called and reported the situation to the company and maintenance. I have turned this situation over to our maintenance department. It might be questioned if I made the correct decision to declare an emergency. My decision was based on the fact that I had no confirmation of my right main gear being down and locked. It seemed to me to be the best decision to have the emergency equipment ready for my passengers if I am landing with only a nose gear and a left main gear. I am responsible for the safety of those six passengers; and with the safety of their lives being my main concern I made the decision to declare an emergency.

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Original NASA ASRS Text

Title: A PA-31 pilot on a charter flight returned to the departure airport and landed under emergency conditions when the gear warning lights failed to indicate the right main gear was down and locked.

Narrative: As I approached my destination; I selected approach flaps and moved the gear selector switch to the down position to lower the gear. I noticed that I had a green indication on the nose gear position light; and the left main gear position light; but no light on the right main gear. I pushed the bulb lens housing (testing the bulb) and I received a green light; so the bulb was good. I then removed the lens cover and did a test again just to make sure; and I received a good indication. I slowed the aircraft to the gear retraction speed and moved the gear selector switch to the up position; retracting the gear. With the gear in the up position I now had a red 'not locked' indicator light indicating the gear was not locked in the up position. I placed the gear selector switch in the down position for the second time to see if the gear would indicate 3 green down and locked position lights. I received the same results as before with the addition of the red 'not locked' indicator illuminated. I repeated this procedure one more time with the same results. I followed the checklist and performed the emergency gear extension procedure. I completed the procedure; felt pressure on the pump; but my primary indicators were still showing the red 'not locked' indicator illuminated and a green light on the nose gear and the left main gear; but no green light on the right main gear. At this point I am concerned and have no confidence the right main gear is down and locked. I am also concerned for the safety of the six passengers I have on board the aircraft. I wanted to fly to an airport that I knew had emergency equipment; so I called approach; declared an emergency and requested to return to our departure airport and to fly by the tower to have the gear visually inspected. The tower indicated all three landing gears appeared to be down. I was vectored behind another aircraft on a 8 mile final and landed safely without incident. I called and reported the situation to the company and maintenance. I have turned this situation over to our Maintenance Department. It might be questioned if I made the correct decision to declare an emergency. My decision was based on the fact that I had no confirmation of my right main gear being down and locked. It seemed to me to be the best decision to have the emergency equipment ready for my passengers if I am landing with only a nose gear and a left main gear. I am responsible for the safety of those six passengers; and with the safety of their lives being my main concern I made the decision to declare an emergency.

Data retrieved from NASA's ASRS site as of April 2012 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.