Narrative:

The pilot flying called for gear down. I selected the gear handle down but the right-hand gear light did not illuminate. We asked for a go around to sort out the problem. They climbed us to 2;000 ft and we passed over the airport so they could check if our gear appeared to be down. They said it did appear down. We went through the 'gear will not extend checklist'. As the checklist states I pulled the t-handle and tried to rotate it to lock; it would not rotate and therefore would not lock in the extended position. I tried different forces and different positions to lock this t-handle but was not successful. I held this handle extended to be able to pull the blow down knob but the blow down knob would not move. My guess is the t-handle must be locked to be able to pull the knob. We finished the checklist and also checked the gear horn warnings by slowing below 150 KTS with the power below 70% N2. We also selected the flaps to 35 and still didn't hear the gear horn. This made us feel relatively confident the gear was down and locked. We declared an emergency and asked for the longest runway. We got vectors around and landed without any incident. We stopped on the runway and were towed off and back to the FBO without any other incident.

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Original NASA ASRS Text

Title: Ce560 flight crew experiences an unsafe gear indication during approach and goes around. Attempts to use the emergency gear extension system are unsuccessful but secondary indications are that the gear is down. An uneventful landing ensues with a tow to the ramp.

Narrative: The pilot flying called for gear down. I selected the gear handle down but the right-hand gear light did not illuminate. We asked for a go around to sort out the problem. They climbed us to 2;000 FT and we passed over the airport so they could check if our gear appeared to be down. They said it did appear down. We went through the 'gear will not extend checklist'. As the checklist states I pulled the T-handle and tried to rotate it to lock; it would not rotate and therefore would not lock in the extended position. I tried different forces and different positions to lock this T-handle but was not successful. I held this handle extended to be able to pull the blow down knob but the blow down knob would not move. My guess is the T-handle must be locked to be able to pull the knob. We finished the checklist and also checked the gear horn warnings by slowing below 150 KTS with the power below 70% N2. We also selected the flaps to 35 and still didn't hear the gear horn. This made us feel relatively confident the gear was down and locked. We declared an emergency and asked for the longest runway. We got vectors around and landed without any incident. We stopped on the runway and were towed off and back to the FBO without any other incident.

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.