Narrative:

As we were on the visual approach my first officer (pilot flying) called for gear down. I selected the gear to the down position but we did not get three green. What we got was green on the left main and nose gears; red on the right main and a yellow on the gear handle. We did a go around; contacted maintenance and operations. I called the flight attendant to ask if the gear looked normal. She said it looked ok. We did a low pass by the tower and they said the gear appeared to be down. We then conducted the emergency gear extension. It did not produce the intended result so we declared an emergency and asked for fire trucks. We briefed the flight attendant and told her to move all the passengers to the rear of the plane. I informed her that we would brace for landing. During the whole situation I made multiple announcements keeping the passengers aware of our situation. When we had all the checklists complete; and the cabin ready; we made the approach for landing. With the flaps set at 35; I touched down as slow as possible holding the right main off as long as I could. The gear held! I came to a stop on the runway and shut down so I could get out and pin the gear. The right main could not be pinned without maintenance action. Maintenance suggested we start # 2 to keep 'gear down hydraulic pressure' in the system. We called for a bus to take the passengers to the terminal and off loaded the people a few at a time so the weight would not change all at once. When the mechanic got there he got the pin in with the tap of a hammer. We were on the runway for over an hour. With the gear now pinned; we taxied to the gate without further incident.

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Original NASA ASRS Text

Title: Upon receipt of a right main gear unsafe light when they extended the landing gear the flight crew of a DHC-8 declared an emergency; unsuccessfully performed the emergency gear extension checklist; prepared the cabin for an emergency evacuation and ultimately landed safely with the right main still indicating unsafe. Gear pins were inserted by Maintenance and the passengers were deplaned and bussed to the terminal.

Narrative: As we were on the visual approach my First Officer (pilot flying) called for gear down. I selected the gear to the down position but we did not get three green. What we got was green on the left main and nose gears; red on the right main and a yellow on the gear handle. We did a go around; contacted Maintenance and Operations. I called the Flight Attendant to ask if the gear looked normal. She said it looked OK. We did a low pass by the Tower and they said the gear appeared to be down. We then conducted the emergency gear extension. It did not produce the intended result so we declared an emergency and asked for fire trucks. We briefed the Flight Attendant and told her to move all the passengers to the rear of the plane. I informed her that we would brace for landing. During the whole situation I made multiple announcements keeping the passengers aware of our situation. When we had all the checklists complete; and the cabin ready; we made the approach for landing. With the flaps set at 35; I touched down as slow as possible holding the right main off as long as I could. The gear held! I came to a stop on the runway and shut down so I could get out and pin the gear. The right main could not be pinned without maintenance action. Maintenance suggested we start # 2 to keep 'gear down hydraulic pressure' in the system. We called for a bus to take the passengers to the terminal and off loaded the people a few at a time so the weight would not change all at once. When the mechanic got there he got the pin in with the tap of a hammer. We were on the runway for over an hour. With the gear now pinned; we taxied to the gate without further incident.

Data retrieved from NASA's ASRS site as of July 2013 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.